[PRICE ONE SIxaj-ixja^^. K ZBTTZR/TO^T'S Modern Photography. COMPRISING PI^CJFICTili INSTRUCTIONS IN WORKING GELATINE DRY PLATES, PRINTING, &o. t (formerly published as theJUU "'1 "ABC OF MODERN PHOTOGRAPHY." BY W. K. BURTON, C.E. ELEVENTH EDITION- LONDON : CABTEE & CO., 5, FUENIVAL STBEET, HOLBORN, E.C. 1894. ST. BRIDE'S STORE, 86, FLEET ST. E.C. MEAGHER'S IMPROVED FIELD AND STUDIO CAMERAS. ESTABLISHED 1858. Have received the Highest Awards wher- ever exhibited, and are used by most of the leading Artists, and supplied to the various Government Departments. INSPECTION IS RESPECTFULLY SOLICITED. MANUFACTORY^ 21, Southampton Row, High Holborn, London, WC. ILLUSTRATED CATALOGUE POST FREE. Discount:— 5 per cent, for Cash with Order. On page inside back cover I told yon one thing to do. On this I tell yon another: — GET YOUR GOODS from the Largest Photographic Stock Warehouse of the World. Undeniably holding finest selection extant. Fallowfield's Central Photographic Stores, 146, CHARING- CROSS ROAD, LONDON, W. This is THE House of Photo. Houses. Remember also to keep you posted and save money. FALLOWFIELD'S PHOTOGRAPHIC REMEMBRANCER AND TRAVELLER • How Buy Handy Books. 1a Apparatus. 2b Dry Plates. 3c Mounts. 4d Sensitised Pap€ ok Chemicals and Developers. 6f Printing and Enlarging. Sent Post Free on receipt of One Penny Stamp to defray postage. flORMTOH-PlCKARD PATENT TIME & INSTANTANEOUS SHUTTER This Shutter is theoretically and practically the most efficient in the market. It gives exposures of any duration from fractions of a second up to minutes or hours without vibra- tion. The same Shutter will fit two or more Lenses. The best Shutter for general all- round work. Speed from T V to ^ of a second, and prolonged Time exposures. Price from 18/6. Speed Indicator 3/6 extra. Focal Plane Shutter. For extremely rapid instantaneous. Range of speed from ^th to ToW^h of a second. Price from 35/-. Snag -Shot Shutter. For Instantaneous ex- posures. Speed T yth to ■^oth of a second. Price from 10/-. THORNTON-PICKARD CAMERA (Ruby Pattern). The most complete and best TT'1 finished Camera in the market. Shutter is attached to Camera Front, and is therefore always in position, and works behind the Lens. Complete, with Shutter, Stand, and three Plate-holders, from £8 lis. Illustrated Catalogue of all the above post free. THE THORNTON-PICKARD MANUFACTURING COMPANY, ALTRINOHAM, nr. MANCHESTER. ESTABLISHED 1830- GOLD MEDALS AND HIGHEST AWARDS AT ALL GREAT INTERNA- TIONAL EXHIBITIONS. FOUR AWARDS AT WORLD'S FAIR, CHICAGO, 1 893. LISTS FREE. BOSS' NEW RAPID HAND CAMERA LENS, F/8. For Finest Work always employ ROSS' LENSES These celebrated lenses are used by Photographers in every part of the world. Over 50,000 have been sold, and intending purchasers are invited to send for a Catalogue before making their selection. ROSS-ZEISS IMPROVED ANASTIGMATIC LENSES. Manufactured by Ross & Co. in five different series[for Studio and Outdoor work. Very fine lenses, carefully calculated, and finished in Ross & Co.'s well-known style. Prices have been revised, and several improvements introduced. ROSS-GOERZ NEW DOUBLE ANASTIGMATS. These new lenses give splendid definition with full aperture, and embrace a wide angle of view. Manufactured by Ross & Co. in two Series, F/8 and F/15. ROSS & CO., Ill, New Bond St., LONDON, W. The oldest Manufacturing Opticians in England. CARTER & CO.'S PHOTOGRAPHIC PUBLICATIONS. BURTON'S MODERN PHOTOGRAPHY. Comprising Practical Instructions in Working Gelatine Dry Plates. By Prof. W. K. Burton, O.E. Price Is., per post Is. 2d. (Eleventh Edition.) BURTON'S POCKET BOOK FOR PHOTOGRAPHERS: Including the usual space for Notes, &c , with Tables for Facilitating Exposures. Price, paper covers, 9d., per post lOd. ; cloth Is., per post Is. Id. OPTICS FOR PHOTOGRAPHERS. By Professor W. K. Burton. Profusely illustrated, and giving full instructions, based on experience, in the use of photographic lenses, together with the theoretical considerations involved. Price Is., par post Is. 2d. A CASKET OF PHOTOGRAPHIC GEMS. A Collection of 500 Dodges, Receipts, Entertaining Experiments, &c, in connection with the Art of Photo- graphy and its branches. Collected, Classified, and Arranged for ready reference. Price Is., per post Is. 2d. LANDSCAPE PHOTOGRAPHER'S POCKET NOTE-BOOK. Arranged for entry of date, light, process, lens, and stop used, number of seconds, time of day, name of place, and remarks. Price 6d., per post 7d. PHOTOGRAPHIC PRINTER'S ASSISTANT. By William Heighwat. Price Is., per post Is. Id. PRACTICAL PORTRAIT PHOTOGRAPHY. A Hand-book for the Dark Room, the Skylight, and the Printing Room. By the same Author. Price Is., per post Is. l£d. ESTHETICS OF PHOTOGRAPHY. By the same Author. Being Hints on Posing and Lighting the Sitter. Price Is., per post Is. ljd. HANDBOOK OF PHOTOGRAPHIC TERMS. An Alphabetical Arrangement of the Processes, Formula, Applications, &c, of Photography for Ready Reference. Compiled by "William Heighwat. Price 2s. 6d., per post 2s. 8d. ELEMENTARY LESSONS IN SILVER PRINTING. By W. M. Ashman. Price Is. 6d., per post Is. 8d. ELEMENTARY TREATISE ON PHOTOGRAPHIC CHEMISTRY. By Arnold Spiller. Price 6d., per post 6£d. PHOTO-MICROGRAPHY ; Or, How to Photograph Microscopic Objects. By I. H. Jbnninos. Also, A CHAPTER ON PREPARING BACTERIA. By Dr. R. L. Maddox. Price 3s., per post 3s. 2d. ART OF PHOTOGRAPHIC PAINTING. By A. H. Bool. Price Is., per post Is. Id. ENAMELLING AND RETOUCHING. A Practical Photographic Treatise. By P. Piquepb. Price 2s. 6d., per post 2s. 8d. THE SPECTROSCOPE AND ITS RELATION TO PHOTOGRAPHY. By C. Ray Woods. Price 6d., per post 7d. CARTER &c CO., (Late PIPER & CARTER) 5, FURNIVAL STREET, HOLBORN, LONDON, E.C. HIGHEST CLAS S PHOTOGRAPHIC INSTRUMENTS. WATSON'S "ACME" CAMERAS & RECTILINEAR LENSES. Press Opinions of the "Acme" Camera. British Journal of Photography. — "It folds into a smaller com- pass, and is lighter and more port- able, than any pattern we have yet seen." Amateur Photographer.— " A wonderful, compact, and fairy- like instrument, exhibiting sever- al new and imp rtant features. Sure to be a favourite with tourist photographers." Photography. — M One of the greatest advances in camera con- struction yet reached, away ahead of anything we have seen." The Camera. — " Messrs. Wat- son have found, by ingenious modifications, how to make the weight still lighter, and the rigid still more firm/' English Mrchanic.'—" For portability and compactness, combiDed with practical utility, this Camera may fairly be said to take the lead, and to be deserving of the title 4 Acme.' " PRICE LIST. "Acme" Camera and three Double Slides Rapid Rectilinear Lens with Iris Diaphragm Solid Leather Travelling Case with spring lock Rotating Turntable in base, and Tripod Stand 6Jx4f 7£x5 8£x6fc 10X8 J2xl0 15x12 | 18x16 £ s. d. 9 12 0 400 I 15 0 220 £ s. d 10 0 0 4 10 0 1 15 0 220 £ s. d. 12 5 0 500 220 220 £ s. d 1400 6 15 0 2 10 0 2 10 0 £ s. d. 16 12 6 8 15 0 300 200 £ s. d.! £ s. d. 21 0 0 31 10 © 11 10 0J16 0 0 3 15 oj 5 10 0 3 3 oj 4 0 0 17 9 0 18 7 0 2r 9 0 25 15 0 30 7 6 39 8 057 0 0 Extra if Camera and Slides are brass bound for hot climates .. r 10 0 1 10 0 r 15 0 200 2 10 0 300 400 18 19 0 19 r7 c 23 4 0 27 r5 0 32 17 6 42 8 0 61 0 0 Any part of the above may be sold separately. Prices are subject to ten per cent, discount four cash with order. *W DRI7F MPflAIQ AWAPRFR includin & Gol <* Medal > Chicago, 1893; Gold OO rnlZX mCUMLO aWIUlUCUj Medal, Antwerp, 1894; two Gold Medals, Paris Universal Exhibition, 1889 ; the medals of the Glasgow and Amsterdam Photo. Societies, 1891 ; Gold Medal Budapesth, 1890; the medal of the Photo. Society of India at Calcutta, 1889 ; the Gold Medal, Melbourne International Exhibition, 1888; the only Medal for Cameras, and the only Medal for Studio and Tupod Stands, at the Great Photographic Exhibition, Crystal Palace, London, 1888 ; the only Medal for Photographic Apparatus, Adelaide International Exhibition, 1887 ; and the orjly Gold Medal for Photographic Apparatus, Liverpool International Exhibition, 1886. Six times placed alone at International Exhibitions, receiving a higher award than any other competitor. A FULLY ILLUSTRATED & DESCRIPTIVE CATALOGUE of Watson's "Acme" and "Premier" Cameras, Rapid Rectilinear and Wide-Angle Lenses, and every Accessory, Appa- ratus, and Material required in Photography, sent post free to any address on application. W. WATSON & SONS. 313, HIGH HOLBORN. LONDON, Estab. 1837. STEAM FACTORIES, 9, 10, U, 16, & 17, Fulwooj e Kknts, W.C. HUSBAND'S West of England Photographic Depot. COLD MEDAL, Melbourne Exhibition, 1880; Dundee Medal, 1882. 8, ST. AUGUSTINE'S PARADE, BRISTOL. HUSBANDS* TOURIST SETS, comprising Folding Camera, Double Back, Lens, Folding Stand, £1 Is., £1 lis. 6d., £2 lOs., £3 3s , £4 4s. HUSBANDS* RECTILINEAR LENSES, h 30/-; h 50/-; b 70/-. SECOND-HAND CAMERAS and LENSES, by brst Makers, constantly on Sale or Exchange. Repairs of all kinds done on the premises. AGENT for PHOTOGRAPEIC APPARATUS, Sec , of the following Makers: — Eastman, Lancaster, Fallowfield, Optimus, Morgan & Kidd, Platinotype. DRY PLATES II fora's* Thomas, Paget, Cadett's, Mawson, Barnett. HUSBANDS' OPTICAL LANTERNS and LIMELIGHT Apparatus. CYLINDERS OP OXYGEN and COAL GAS, Regulators, Guages, &c Large Stock of Slides on Sale or Hire. lantern Catalogues post free 6d. PHOTO MECHANICAL PROCESSES. EVERY REQUISITE SUPPLIED BY PENROSE cfc 00, Tie PMo. Process Stores, 8 & 8a, Upper Baker Street, Clerfcenwell, London. Sole Agents for LEVY'S SCKEENS for the Half- Tone Process. MONTHLY CIKCULAR AND LIST ON APPLICATION. (Late PIPER & CARTER) ARE PREPARED TO UNDERTAKE ORDERS FOR PRINTING Books, Pamphlets, Magazines, Newspapers, Periodicals, And Every Description of Printing. 5, FURN1VAL STREEtThOLBORN, E.C. Magic Lanterns and Slides. Walter Tyler's Helioscopic is perfection of all Lanterns, supplied to the Indian Government, School Boards, Science Classes, Clergy, and Exhibitors throughout the world. Impossible to have lanterns give better definition or more satisfactory results ; specially constructed lens, which no other lantern possesses. Walter Tyler's Best Triples and Biunials are unsurpassed, and perfect in every detail. Good Biunials, mahogany bodied, brass fronts, and all improvements, £7 10s. ; Single Lanterns with 4 in. condensers, portrait front lens, 4- wick lamp, complete in case, 27s. 6d. Lantern Lenses. — Specially constructed. Walter Tyler's New Helioscopic Portrait Combination Lantern Lens gives the most perfect definition and brilliancy, can be fitted to any lantern, and for excellence cannot be surpassed. Regulators and Guages. — Great reduction in price. The largest stock of Gas Cylinders in England. Best seamless steel, tested and valved, all sizes at very low prices. Oxygen or Hydrogen Gas, of best quality and specially low prices, in Walter Tyler's or customers' own cylinders. Slides from Negatives and Pictures. — Walter Tyler Manufactures and Colours Slides on the premises, thus ensuring speedy delivery, and prices are most moderate. Biunal Lanterns. — If you are in want of a really good Biunial Lantern, perfect in every respect, call and see Walter Tyler's entire brass -fronted, mahogany-bodied, lined with Russian iron, and fitted with new best quality lenses, and sold at a most moderate price. The top lantern will take a l-wick lamp. These are great bargains. Hire Department is now perfect. Largest and best collection of Slides in the world ; over 300,000 always in stock. Temperance, Travel, Scripture, Educational, Comic, Tales, &c. Cheaper than any other house ; no extra charge for coloured slides or effects. Special terms for large quantities. Lantern Slides. — If you wish to Hire, Purchase, or Exchange, you cannot possibly do better than go to Walter Tyler, who makes this business a specalitC, and you will thus save dealers and all intermediate profits. Second-hand Lanterns and Slides at very Moderate Price*, also all kinds of Apparatus. Send for Large Catalogue, 500 pagee, with instructions for working lanterns of all kinds, and costing an immense sum to produce ; sent free for 6 stamps. Small Catalogue ancjl Second-hand List, post free. WALTER TYLER, 48, 50, & 94, Waterloo Road, London. THE STEREOSCOPIC COMPANY'S ' BINOCULAR HAND-CAMERA ' Weighs, when loaded with 12 Plates or 30 Films, 19 ozs. only, but gives a picture measuring 7 by 5 inches. The BINOCULAR CAMERA' No. 1, IS a complete photographic apparatus, containing, within the ppace occupied by a small field glass, a rapid rectilinear lens of the highest quality, an instantaneous shutter, and one dozen prepared dry plates or thirty films. There is also a finder or sighting glass, which permits of the exact size and appearance of the proposed picture being seen at the time of pressing the button. The plates are automatically and instartaneously changed. The shutter is also arranged to give time expr surc-s, so that, besides taking pictures of moving objects in a good light, the Camera can be used for home portraits in ordinary rooms, inteiiors, and out-door work in dull weather One very important advantage possessed by this instrument over all other hand Cameras is found in the fact that in consequence of the ' Binocular ' being held up to the eyes whilst the picture is being taken, the resulting photograph exactly represents the view as seen by a person of ordinary stature, and not as it would be seen by a child three feet bigh. Although the negatives are necessarily of small dimensions, they are of sucb exquisite sharpness that they will bear enlarging to a considerable extent without loss of definition. This is most onveniently done by means of the special enlarging apparatus. The focus of the lens in this is permanently adjusted, and it is only necessary to place the negative in the frame at the one end, and the bromide paper or film in the other, and give a brief exposure to daylight. Thus it is actually as easy to make a print upon paper 7x5 inches as it would be to make one by contact in an ordinary printing frame. Nor is the enlarging apparatus itself a heavy or bulky instrument, measuring as it does only 8£ X 8§ x 6^ inches, and weighing less than 3f lbs. It is, of course, understood that the enlarging apparatus is kept in the laboratory, the Camera only (weighing 19 ozs J being required in the field. The small negatives answer admirably for printing lantern slides by contact, or prints from the same may be used for illustrating a diary or letter. The 4 BINOCULAR ' CAMERA, No. 2, Is constructed upon the same principles, but takes 18 plates 3 J X It is a perfect instrument for producing negatives for printing lantern slides by contact. PRICE OF ' BINOCULAR ' CAMERAS. Eor plates £5 5 O „ films 5 5 0 * With Zeiss lens of extreme rapidity (//6 3), enabling instan- taneous pictures to be taken without sunlight 12 12 0 * No. 2 4 Binocular 9 Camera, taking pictures 3^x2| 1 0 1 0 O * With Zeiss lens 17 17 O * These Cameras are fitted with the improved shutter, with pneumatic time exposure- attachment. THE STEREOSCOPIC CO., lOO & 108, REGENT STREET, W., And 54, CHS AF SIDE, X.CNDOK. MODERN PHOTOGRAPHY. COMPBISIISTG PRACTICAL INSTRUCTIONS IN WORKING GELATINE DRY PLATES, PRINTING, ETC. FOBMEBLY PUBLISHED AS THE "ABC 0!P MODERN PHOTOGRAPHY.'* By W. K. BURTON, C.E. ELEVENTH EDITION, REVISED AND ENLARGED LONDON : CARTER & CO., 5, FURNIVAL STREET, HOLBORN, E.C. 1894. LONDON : CARTER AND CO., PRINTERS, FURNIVAL STREET, HOLBORN, E.C. PREFACE TO THE ELEVENTH EDITION. It is but a short time since this little book was nearly entirely re-writ ten, the changes in photographic practice having made such a course desirable. The writer thought at that time that at least several years would elapse before anything farther in the way of revision than the correction of a few errors that had slipped into the ninth edition would be needed. So rapid, however, are the advances of photography in these days that something more is necessary, and the whole work has been thoroughly revised. Additions have been made, and also here and there alterations that have been suggested by practice. Imperial University, lokio, Japan. PUBLISHERS' NOTE ON TEE ELEVENTH EDITION. The fact of " Burton's Modern Photography" being, perhaps, the most reliable and practically useful of the handbooks of photography, may reasonably lead the reader to expect much from the New Edition now placed in his hand ; and certainly, in expecting the work to be brought well up to date, he will not be disappointed, in spite of the fact of the Author being resident in Japan. The time which has elapsed between the sending of the manuscript of the book, and its production in print in London, has in no way made it uncurrent or behind the times, and the number of new or modified forms of anastigmatic lenses which have appeared during the past two months merely serves to emphasise the vi PREFACE. position which Professor Burton takes upon pages 48 and 49 : that for the greater part of the usual run of pictorial work it is doubtful whether the advantage of such forms compensates for the additional expense, although in the case of line work, or such special tasks as photo-grammetrical surveying, the advantage of the new instruments is undoubted. As regards the newer developers, nothing need be said in extension of the remarks contained in Chapter XII. ; in spite of all " advance," pyro-and-ammonia still leads the way, and is used regularly by the most successful workers. At any rate, the newer developers are of such doubtful advantage that Professor Burton is fully justified in the position he takes with regard to them; and even if he were now in London to revise the proofs of his book, it is doubtful whether he would add a word to Chapter XII. THE PUBLISHERS. i CONTENTS. PAGE Introduction 1 CHAPTER I. Sslection of Apparatus 6 CHAPTER II. Chemicals 15 CHAPTER III. The Dark Room 20 CHAPTER IV. Exposure of the Plate 27 CHAPTER V. First Lesson in Development 32 CHAPTER VI. Lenses 37 CHAPTER VII. Management of the Camera in the Field — The Swing-Back, Rising- Front, &c 50 CHAPTER VIII. Instantaneous Photography and Hand -Camera Work ... ... 61 CHAPTER IX. Portraiture ... 71 CHAPTER X. Tables to Facilitate Judgment of Exposure ... 78 CHAPTER XI. Second Lesson in Development .. ... . ... 90 CHAPTER XII. Various other Developers in Use ...100 CHAPTER XIII. Defects and Remedies 114 viii CONTENTS. PAGE CHAPTER XIV. Intensification and Reduction of the Negative — Varnishing 123 CHAPTER XV. Negatives on Paper and other Flexible Supports 129 CHAPTER XVI. Printing and Toning with Ready-Sensitised Paper 136 CHAPTER XVJI. Sensitising Albumenised Papers 148 CHAPTER XVIII. Various other Silver Printing Processes 152 CHAPTER XIX. Defects in Silver Prints, and Remedies ... 162 CHAPTER XX. Platinum Processes 166 CHAPTER XXI. Vignetting — Printing of Skies into Landscape Negatives 174 CHAPTER XXII. Mounting, Rolling, Burnishing, and Enamelling Prints 178 CHAPTER XXIII. Transparencies — Lantern Slides — Enlarging and Reducing ... ... 182 CHAPTER XXIV. Manufacture of Gelatine Emulsion ... 192 CHAPTER XXV. The Ammonia Method of Emulsion Making 201 CHAPTER XXVI. Preparing Glass : Coating It.— Drying and Packing Plates 210 CHAPTER XXVII. Concluding Remarks 215 Weights and Measures 219 Solubilities of Photographic Chemicals ' 220 Index 221 BURTON'S MODERN PHOTOGRAPHY. INTRODUCTION. I wish at the cutset to explain my reason for writing this little book, and the object which throughout I shall attempt to bear in mind. After Archer brought out his collodion process, phonography for the first time became a popular amusement with t, ^se who had a leaning to art or science, or both. The scientific interest and novelty attaching to the then comparatively new process, combined with a totally false idea of how easy it would be, by means of it, to make a "picture," attracted enormous numbers of those who had some spare time on their hands to take up the subject as amateurs. After a while, many of these found that their expectations were scarcely realised, and they found, too, to their surprise, that a mere transcript from nature was not necessarily a picture, but that as much art- culture, if not as much skill, is needed to produce such when the tools are the camera and lens, as when they are the pencil and brush. They found, also, that the skill required was greater than they had supposed — that, at least, a slight knowledge of chemistry and of physics was necessary, or endless troubles would arise. 2 INTRODUCTION. The realisation of these facts greatly thinned the ranks of the amateurs. Another era has, however, now arisen in photo- graphy — the era of the dry gelatine process. The technical skill necessary to produce a photograph has been greatly reduced. The plate is now no longer prepared by bringing into contact, immediately before exposure, two fickle and uncertain chemical preparations — the " collodion " and the " bath " — but it may be purchased ready-made, will keep for a very long period, and may be exposed at any time. True, the artistic feeling is as necessary as ever; but that uncommon combination, a mind equally artistic and scientific, is needed to a less degree than before, and wider scope is given to the former capacity. The consequence of this is, that the number of amateurs is now enormously on the increase. The man who has but a few summer days to spare may take the camera, and may work it with profit. There will probably be soon — if there is not now — an army of amateurs as great as there was twenty years ago. The ranks are continually being recruited, and greatly by those who have worked no other process before the gelatine one.* Now I come to the object of this little work. How is the dry-plate aspirant, who takes up the gelatine process as his first, to gain the necessary information to enable him to practise the art ? If he has a photographic friend — if his friend and he have coincident spare hours, and if his friend has the ability of conveying to others the knowledge which he himself possesses (an ability rarer than is generally supposed) — then the way whereby the would-be photographer is to gain his information is clear.f * There are certainly more amateurs at the present time than there ever were before. t There are now several institutions in which photography is excellently taught. If the beginner can attend one of these he certainly ought to do so. INTRODUCTION. 3 In very many cases, however, the beginner has no such friend ; then, where is he to turn ? True, there are several excellent manuals published on the gelatine process, but these are quite unsuited for beginners; they presuppose a general knowledge of photography — at least, of the "wet process."* Then there are the directions contained in the boxes of plates which the tyro will purchase. They also are excellent in their way, but they are necessarily laconic, and they, as well as the manuals, are addressed to those who already are not unacquainted with photographic processes. They constantly refer to the collodion process as a standard, and they use technical language which is unintelligible to the beginner. Let any experienced photographer whose eye this may happen to meet try to cast his mind back to the times when he was tediously wading through the beginning of whatever was the first photographic process he worked. Can he remember when terms now so familiar to him, such as " detail in the shadows," " density in the high-lights," conveyed no idea to his mind ? Perhaps he cannot ; but such a time there certainly was for him, and now is for everyone who first attempts to solve the mystery of the language in which the modern dry-plate manuals and instructions in the plate-boxes are couched. I know the case of many who have begun photography since gelatine became popular, and who, feeling the want I have attempted to explain — of anything to guide them to a direct knowledge of the working of dry plates — have familiarised * It must be borne in mind that this was written substantially as it here stands in the beginning of 1882. I have left it with hardly any alteration, rather that any who read it may appreciate the huge changes that have taken place in the past ten years than for any other reason. What percentage, I wonder, even of professional photographers, would find instructions intelligent that constantly referred to the " wet process " as a thing familiar to them as a matter of course ! B2 4 INTRODUCTION. themselves with the more difficult wet process for the sole purpose of using it as a stepping-stone to the former. In speaking of the gelatine process as easier than the collodion, it must be understood that I do so on the assumption that the dry plates are purchased from the manufacturer, not made by the photographer himself. No beginner should attempt to make his own plates. He will find that he has quite enough to do to learn to work those that are made for him by others. In fact, I consider that the most experienced photographer who is wise will buy his plates, unless he ta'kes an actual scientific interest in the manufacture. Dry plates can now be had so cheaply that he can scarcely expect to save money by making them. This, however, is a digression. To return to the subject. What I intend to do is to give instruction in the working of modern dry plates, addressed to the merest beginners. I shall use no technical terms, or only such as I have already explained, and shall assume no knowledge of any photographic process what- ever. My endeavour will be to give such instructions that those beginners who follow them carefully may, without any other assistance, after a little practice, be able to turn out, with a fair approach to certainty, technically perfect negatives on plates purchased from any trustworthy maker, and to make prints from the negatives, so as to enable them to complete their pictures. I shall avoid theory altogether ; nor do I intend to enter into the question of art. All I propose to do is to teach the A E C of the subject — the purely technical. To the higher branches of photography — the artistic — the aspirant must be guided mostly by his natural gifts ; but he will find much to assist him in many advanced books on photography. In fact, my desire is to produce a manual of photography for beginners, on the assumption that the gelatine process is now the photographic negative process of the day. INTRODUCTION. The last chapters will consist of concise instructions for the making of emulsions and coating of plates, so that the amateur who chooses, for pure love of so doing, to make his own plates, may do so. Here, again, I intend to avoid all theory, nor shall I enter at all deeply into the question of emulsion making, as the subject has been very fully treated in two different manuals published by Messrs. Piper and Carter.* I intend to devote a chapter to the subject of lenses, and to give a few very simple rules whereby the beginner may gain some idea of the exposure that will be needed in different circumstances, and certain tables which will, for most cases, do away with the necessity for any calculation even of the simplest kind. It is common in manuals for beginners to say that knowledge of the length of exposure can only be gained by ex- perience. This is partly true, but not entirely. Some idea may be given of how long the cap should be kept off the lens in certain circumstances, and this, I believe, will greatly assist the beginner. The writer remembers how, when he began the study of photography, with no assistance but such as he could get from the handbooks, he sought in vain for at least some faint clue to the length of exposure, and to the factors regulating it. The subjects of enlarging and lantern slide making will be briefly treated. * "Photography with Emulsions," by Captain Abney ; and " Modern Dry Plates," by Dr. J. M. Eder. CHAPTER I. SELECTION OF APPARATUS. The first thing that the photographic beginner has to do, after he has made up his mind that he is going to take up the fasci- nating art, is to determine what size of " plate 99 he will work — that is to say, how large his pictures are to be. As a matter of course, he should begin work upon the smallest plates he can buy, as the first few results are sure to be far from perfect, and the cheaper the plates spoiled the better. This does not, how- ever, bind him to the smallest size. All photographic cameras are made so that several different sized plates will fit them, and after the first difficulties are over, the tyro is sure to aspire to the production of something larger than the well-known " card " or carte-de-visite. In considering size of plate to be worked, it must be borne in mind that the larger the plate the greater the weight to be carried into the field, the greater the difficulty of manipulation, and the heavier the expense at every turn. This being the case, I suggest, as a good size, that known as " half- plate that is, a plate measuring 6 J inches by 4f inches. This allows of pic- tures being taken of the popular cabinet size, and the apparatus necessary can very easily be manipulated in the field. A some- what larger size — say 7£ by 5, which gives a landscape of very pretty size and shape — can easily be carried by an active man ; SELECTION OF APPARATUS. 7 but I think that, at any rate, nothing greater than " whole- plate/' or 8J inches by 6J inches, should be attempted at first. The smallest size of plates commonly offered for sale is the " quarter- plate," measuring 4£ inches by 3£ inches, and, as has been said, the beginner should confine himself to this size till he has become somewhat familiar with the different operations involved in the taking of a negative. There is a natural tendency, at the present time, on account of advertisements of the " you pull the string, we do the rest " kind, for the beginner to take to hand-camera work. Now I am going to say nothing against the hand-camera, as I become daily more convinced of its usefulness, but I consider that hand-camera work is not for the beginner. To work a hand-camera needs all the skill that is necessary to work an ordinary camera, and some additional skill besides. If the photographer intend to confine himself to plates not larger than 3£ by 4£, or at the most 5 by 4, there is no harm in getting a hand-camera of one of the many kinds that can be used as an ordinary camera on a tripod. At first it should, of course, be used in this way. As for those folks who go in for shooting with a hand-camera at all and sundry, not even attempting to gain any knowledge of photography, and then send the plates or films to be developed by a professional photographer, all I can say is that nothing in this book is written for them. It may be a question whether glass or films should be worked. Films are made of excellent quality in the present day, and the subject of them is treated farther on, but, on the whole, I strongly recommend glass for the beginner. Having decided the size, the next thing to consider is in what manner to purchase the apparatus ; and here let me say em- phatically that the only way in which to be sure of getting reliable photographic negatives is to go to a first-rate dealer and to purchase them new from him. There is a general idea 8 SELECTION OF APPARATUS. in the mind of the non-photographic public, probably gained from seeing numbers of old cameras and lenses exposed for sale in pawnshops and such like, that great bargains are to be made in second-hand photographic apparatus, and that the beginner may H pick up " what he wants very cheaply by a little looking about. There can be no greater mistake. The experienced photographer may pick up a very cheap article ; but the man without technical knowledge is almost sure, if he attempt to do the like, to find on his hands goods that will be useless to him when he has somewhat advanced in his art.* Having thus advised the reader where to purchase his appa- ratus, there still remains the question, " How ? Is it advisable to go in for a complete set, or to buy each article separately? " The beginner will be best advised in this matter by the state of his funds. The " sets " made up by most of the chief photo- graphic dealers are most excellent and complete ; but the sum charged for them is greater than many are willing to lay out at once. These may buy at first only such articles as are absolutely necessary to begin with, and may add to their store from time to time as they think fit. I give a list of the articles most neces- sary for working quarter-plates, and afterwards shall say a word on such of them as seem to call for special description : — A camera. A lens. A tripod stand. A focussing cloth. 3 flat dishes or trays of porce- lain or other material. Graduated measure holding £-ounce. Ditto, ditto, 4 ounces. A dozen gelatine ^-plater. A darkroom lamp. A cheap chemical balance. * This does not refer to those few respectable dealers who make the sole of second-hand photographic apparatus a special part of their business. The writer has found these reliable, and generally very accommodating iu effecting exchange of apparatus, and so forth. SELECTION OF APPARATUS. 9 The Camera. The general form of the photographic camera must be familiar to all. It consists essentially of a box, at one end of which is held a sensitive plate, whilst at the other is held a lens. An inverted image of any bright object which may be opposite the lens is thrown by it on to the sensitive plate. There is a means of adjusting the distance between the plate and the lens, or, as it is commonly expressed, of focussing. Every camera has, besides this, a piece of ground glass, which can be put in the exact place to be afterwards occupied by the plate, and upon which the image can be seen so as to facilitate focussing. It is also fitted with a " dark slide." This is a sort of case in which a sensitive plate may be fixed. After the camera has been focussed, the dark slide is placed in the position before occupied by the ground glass, which latter is removable. The " shutter,' * or sliding door of the dark slide, is then removed, and, on taking the cap off the lens, the image falls on the plate. As many dark slides as are wished may go with a camera, and thus a number of plates may be carried into the field. Slides are constructed to hold two plates each, and are called " double dark slides." These are by far the best and most convenient to use for dry plates. Three slides are a common number to go with a camera. This enables half a dozen plates to be carried out. Each dark slide should be fitted with a set of " carriers." These enable plates smaller than the largest size for which it is constructed to be placed in it.* 11 modern cameras for use in the field are made so that they oan fold up into small compass for ease in carrying, and have " bellows bodies," that is to say, can be drawn out and in like a * See chapter which treats of sensitive films to take the place of glass plates. 10 SELECTION OF APPARATUS. concertina. "We illustrate three of the best modern forms of camera, showing in each the camera as in use, and as folded down for transportation. In purchasing a camera, the photo- grapher should get one which will open to a considerable dis- tance — if possible, to as much as twice or three times the length of the largest sized plate which it will work. In some part of his career the amateur is sure to aspire to the taking of portraits. His attempts in this direction are likely to be failures, and to cause great pain to his friends ; but nothing is surer than that the portrait fit will attack him. When it comes to this, he will find a camera that opens to a considerable length a great advan- tage. Even apart from the matter of portraits, a camera opening to a considerable length is desirable, as it is now becoming a generally recognised fact that more arti&tic pictures are got with * See chapter on Photographic Optics. 12 SELECTION OF APPARATUS. There are various adjustments attached to modern cameras which, although of little use in the hands of the beginner, will he found of great convenience to him when he is more advanced. These are chiefly a vertical and horizontal adjustment of the front on to which the lens is screwed, and what is called a " swing back." This latter provides a means of varying to a certain extent the angle between the sensitive plate and the axis of the lens. Its action will be described in a subsequent chapter. A leather case, in which the camera and dark slides can fit, should be provided. Various attempts have been made to obviate the necessity of having separate dark slides, and cameras have been constructed so that they either contain a supply of plates themselves, appliances being added to enable these to be brought into position, or so that the plates are contained in a box from which they may be transmitted to the camera without the intervention of more than one dark-slide. Some of these are by no means unsuccessful in practice, but, on the whole, I incline to prefer double dark slides to any of them ; at any rate, for sizes over by 4f . Tor very small plates, on the other hand, " changing boxes " are a decided convenience. The Lens. Next in importance to the camera — if, in fact, it is not more important — comes the lens. As it is intended to devote a special chapter to lenses, I shall not go much into the question just now, but shall merely say that, for all-round work, the most useful forms of lenses are those sold as " rapid rectilinear, " and 4 ' rapid symmetrical. " These lenses were, until recently, made with a maximum aperture not exceeding one-eighth of the focal length. ]Sow some opticians make them with an aperture between a fifth and a sixth of the focal length. These extra- rapid lenses will be found very useful for sizes up to and SELECTION OF APPARATUS. 13 including 6J by 6£, or even 7| by 5, especially making excel- lent portrait lenses ; but for larger sizes they are not to be recom- mended, at least, to the photographer who is confined to the use of one lens, as, for certain reasons that it is unnecessary to describe here, advantage can seldom be taken of the extra large aperture in the case of the larger lenses. A cheaper and very useful lens, though not so rapid as that just described, is one of the " single achromatic " lenses of modern design. The " wide- angle " landscape lens mentioned in former editions of this book is an excellent one for special work, but is not to be recommended for all-round work unless of a focal length to cover a plate several sizes larger than that actually used with it. Indeed, whatever form of lens be adopted, the focal length should be from 1 J to lj- the length of the largest plate to be worked, whatever the catalogue may say about the covering power of the lens. (See chapter on Lenses.) The tripod-stand calls for little special remark. Its general form is known to all. In stands of modern construction each leg folds into two, or sometimes into three, so as to make the whole more portable ; and in some cases each leg has a sliding adjustment. The chief requirements of the camera- stand are that it should be light, be easy to fit up and take down, and should be rigid when fixed up. The focussing cloth is intended to cover the head and ground glass, thereby shutting out extraneous light, and making it possible to see the image given by the lens sufficiently dis- tinctly to adjust the focus. It should be about four feet square for small sized cameras. Velvet or velveteen is the best material to use, but any black and opaque cloth will do. The flat dishes or trays — or, as they are sometimes called, flat baths — are for use in the operation of developing, fixing, &c, to be described in a future chapter. Such dishes, made of so-called porcelain, can be had for a few pence each and upwards, 14 SELECTION OF APPARATUS. and I recommend that these be purchased for quarter-plate work. "When the photographer advances to larger sizes, he may indulge in the more expensive and more convenient dishes made of ebonite or other light material. The dry plates can be bought from any photographic dealer. They are extensively advertised in the photographic periodicals ; but I cannot take upon myself to recommend one make in pre- ference to another. I have found almost all excellent, the cheap as well as the more expensive. It will be found advis- able, at first, to use those sold under such names as " ordinary," " landscape," and to avoid the very rapid makes. The dark-room lamp will be described when we come to the chapter on the " Dark -Boom." The most convenient balance for photographic use is such a one as druggists weigh out their chemicals in; but a small pair of scales without stand, such as is sold for about half-a- crown, will do well. For practical photography, weighing apparatus of great delicacy is by no means necessary. A set of grain and drachm weights are needed. The system known as " Apothecaries' weight" has been adopted throughout this book, because it is that most generally used for practical chemi- cal and photographic work in this country. But it is unneces- sary to say that the Trench decimal system is vastly superior. In the case of all formulas, a corresponding formula in French decimal measures and weights is given in a foot note in the present edition. It has not been attempted to make these correspond exactly with the English weights and measures. It would involve many odd figures, and often many decimals, to do so ; and, as photographic formulae are generally very elastic, it is considered that it will be of more convenience in practice to give formulas that are practically correct, and that are in round figures, than to exactly reproduce the proportions given in the English formulas. CHAPTER II. CHEMICALS. After the photographer has provided himself with the neces- sary apparatus and plates, his first consideration must be the purchase of the chemicals which he will need to convert his plates into negatives. A list is given of these, stating after each about the quantity I think it desirable that he should possess himself of at first. Afterwards are given a few words describing the general properties of each substance, but not entering into the chemical composition. Each chemical, whether liquid or solid, should be kept in a bottle, which should have the name distinctly labelled upon it, if possible, in print. The chemicals needed are as follows : — Pyrogallic acid 1 ounce Ammonia of specific gravity '880 3 or 4 ounces Carbonate of potash ... ... 1 pound Sulphite of soda ... 1 Eromide of potassium 1 ounce Citric acid ... 1 Hyposulphite of soda ... 1 pound Alum... i Methylated spirit i pint Bichloride of mercury 1 ounce Negative varnish ... A few ounces 16 CHEMICAL?. A couple of books of test papers, one of' blue litmus and one of red litmus. Pyrogallic Acid is a white, feathery, and extremely light body. It is exceedingly soluble in water. It is a powerful absorber of oxygen, especially when alkaline. "When a solution of it has absorbed oxygen it turns brown. The Ammonia used in photography is the strongest solution of ammonia gas in which it is possible to make water at atmo- spheric pressure, and has, or is supposed to have, a specific gravity of *88. Ammonia is the well-known hartshorn. It is a transparent and colourless fluid. It is powerfully alkaline. When the stock has been purchased, it is advisable to pour it at once into a bottle holding exactly double the amount of the ammonia, and to fill up the bottle with water. If this is not done, the stopper of the smaller bottle may be blown out by the pressure of the liberated ammonia gas when the weather is warm. This will destroy the whole, as, on exposure to air, the liquor ammonia rapidly becomes weaker, because the ammonia gas escapes.* Carbonate of Potash is in the form of a heavy white powder, or of very small white crystals. It is deliquescent, and the bottle containing it should be kept well corked or stoppered, * Great caution should be used in opening bottles of this very concen- trated ammonia. Twice it has happened with the writer that, opening a bottle of '88 ammonia, there has been no motion for a second or two, after which violent ebullition has taken place, and nearly the whole of the contents of the bottle have been blown out with such force as to strike the ceiling of the room. In these cases no harm resulted farther than, in one of them, the bottle being a "Winchester quart," containing half a gallon, the inmates of the whole house had to make for the open air, and could not return for some half an hour or so. The writer has, however, just heard of a case in which the ammonia was driven straight into the face cf an amateur photographer, who thereby totally lost the use of one eye. CHEMICALS. 17 otherwise the potash is liable to absorb much moisture. It is very readily soluble in water. Sulphite of Soda is in the form of irregular white crystals. It is liable, on exposure to the air, to become oxidised into sul- phate of soda, in which form it is useless for the purpose for which it is intended in photography. The bottle containing it should, therefore, be kept tightly corked or stoppered. The crystals should be clear and transparent. If they are covered -with a white powdery deposit it is likely that the sulphite has been partly oxidised. Sulphite of soda is very readily soluble in water. Bromide of Potassium is usually found in the form of fairly large crystals of regular structure. It is very readily soluble in water. Citric Acid is met with either as clear, colourless crystals, or as a powder. It is soluble in water. Hyposulphite of Soda is a clear, colourless, crystalline body, slightly deliquescent. It is readily soluble in water. The Alum used may be the ordinary alum sold by grocers. As it is intended to be dissolved in water, it should be bought in the form of a powder. It does not dissolve in very large quantities in cold water, and dissolves somewhat slowly. It dissolves readily in hot water when it is in the form of powder. Methylated Spirit calls for no particular notice, as it is well known to all. For all purposes where " methylated spirit" is mentioned here, the new spirit containing a small quantity of mineral oil will do. "Where " alcohol" is mentioned, it is to be understood that " methylated spirit" must not be used. The liquid sold as " finish " is not suitable for photographic purposes. Bichloride of Mercury is a whitish crystalline substance. It is sparingly soluble in water, and is an active poison. It is commonly known as corrosive sublimate. 18 CHEMICALS. Negative Varnish in appearance is very like the ordinary spirit varnish used for varnishing wood, but generally differs from it in the resin used in its manufacture. It can be bought from any photographic dealer. That sold as " dry plate nega- tive varnish " is the most suitable. The Test-Papers are for discovering whether a liquid, such as a solution of any salt, is neutral, acid, or alkaline. To use them, we proceed as follows : — Suppose we have a solution of whose condition as regards acidity or alkalinity we are ignorant. A small piece of the blue litmus paper is dipped into the solu- tion. If the paper change its colour to red at once, or after a short time, the solution is acid ; if no change in its colour take place, the solution is either neutral or alkaline. In this latter case, a piece of the red litmus paper is dipped into it ; we now know the exact condition of the liquid. If the red litmus become blue, the solution is alkaline ; if no change take place, it is neutral. I have now enumerated and shortly described the necessary chemicals for "beginning photography, and shall give instructions for mixing a few of what are called " stock solutions.'* These are solutions which may be kept for some time, and that the photographer should have by him. The ones described are those to be used in the first lesson in development. Stock Solution. No. 1 bottle to be labelled " Ten per cent. Solution of Pyro- gallic Acid" in large letters, so that it may be read in a dull light. We take four ounces of sulphite of soda, and one dram of citric acid, and add warm water till the whole measure about nine ounces, stirring till the crystals are quite dissolved. We then pour the solution over the pyrogallic acid in a fresh one-ounce bottle. The pyro will dissolve instantly. We then CHEMICALS. 19 make the whole quantity up to ten ounces.* This may be looked upon as a ten per cent, solution of pyrogallic acid merely, the only function of the other chemicals being to prevent the spontaneous oxidation of this substance, and the consequent deterioration of the solution. No. 2. Ten per cent. Solution of Carbonate of Potash. — This is made simply by placing one ounce of carbonate of potash in a measure, filling up to ten ounces with cold water, and stirring with a glass rod till the salt is melted. \ No. 3. Alum Solution. — Three or four ounces of the alum are placed in a pint bottle. This is filled up with warm water. The whole of the alum will probably dissolve, but some of it will be thrown down again as crystals when the solution becomes cold. As long as these last, more water may be added from time to time, as the solution is used. When they are all dissolved, more alum must be added. No. 4. Fixing Solution. — Five ounces of hyposulphite of soda or " hypo " are placed in a pint bottle, which is filled up with warm water, and shaken till the crystals are dissolved. Common tap-water may be used for all these solutions, which, stated briefly, are as follows : — No. 1. Ten per cent, solution of pyrogallic acid. No. 2. Ten per cent, solution of carbonate of potash. No. 3. Saturated solution of alum. No. 4. Twenty-five per cent, solution of " hypo." * Sulphite of soda 120 grammes Citric acid ... 4 „ Pyrogallic acid ... 30 Water enough to make up to 300 c.c. t Carbonate of potash 50 grammes Water sufficient to make uo to 500 c.c. CHAPTER III. THE DARK ROOM. The reader will understand that the plates he is about to work with are of the most " exalted sensitiveness " ; that is to say, a very small amount of light allowed to act on them will produce a change which may be made visible. It must be explained, however, that only certain rays of light have the power of making the change here mentioned. All readers who have a little knowledge of physical science know that white light is in reality a combination of light of all the beautiful colours we see in the rainbow, and that if we pass a ray of white light through a prism, it will be broken up into all these colours. The order of them is : — Yiolet, indigo, blue, green, yellow, orange, and red. Those at the beginning of the list are called rays of high refrangibility ; those at the end, rays of low refrangibility. Now, it is a curious fact that the photographic change which is worked on the ordinary sensitive plate is worked almost entirely by the rays of high refrangibility, principally by the violet and blue, and certain invisible rays even more refrangible than these, which are said to be " actinic "; whilst the red, which is said to be " non-actinic," has no appreciable effect. Were it not for this peculiar fact, photography would be almost impossible, because we could lind no light in which we could manipulate our plates without THE DARK ROOM. 21 their being affected, and consequently destroyed. As it is, however, we only need to secure some place illuminated by those rays that have very little photographic action, and we can work with tolerable freedom. In other words, we want a room lighted with only red, orange, or yellow light in which to work. Until recently it was supposed that the modern sensitive dry plates could not be worked but in the deepest of ruby light. Thanks, however, to Mr. W. E. Debenham, we now know that it is quite as safe to work in orange, or even yellow light, as in ruby ; that, indeed, if the proper shade of yellow be got, it is probable that more visual light may safely be admitted than when the colour is ruby. Photographers give a room lighted with only non- actinic light the name of " dark-room,' } although the term is a misnomer. On the " dark-room,'' then, I propose to give what hints I con- sider necessary for the beginner. It is scarcely to be expected that the young amateur, taking up the subject of photography for the first time, will be able to obtain the exclusive use of a room of considerable size to convert into a dark-room ; he will probably have to put up with some temporary arrangement ; nor is it at all necessary, even when he advances considerably, that he should have a permanent dark-room, unless he intends to make his own plates. Any room or closet from which all rays of white light can be shut off may be conveited into a dark-room, in which plates may be changed and developed. If a room having a sink and water-tap — if, say, the pantry — can be u annexed" for the time being, the trouble will be greatly reduced ; but it is quite possible to make shift with a pail for a sink, and a water-jug instead of a tap. I have said that it is necessary to shut out entirely all day- light. This pre- supposes the use of artificial light for illumin- 22 THE DARK KOOM. ating the apartment with the necessary red or non-actinie light. I think that until such time as the student sees his way to fitting up a permanent dark-ioom, he will find it best to work with artificial light. Indeed, many, the writer amongst others, who have permanent dark-rooms, prefer to use artificial light, even in the daytime, because it varies less than daylight. Lamps constructed especially for the purpose of giving " safe light " are sold by all dealers in photographic apparatus. These use either gas, oil, or candles, and all consist of an arrangement whereby the air necessary to support combustion is introduced by passages which will not allow white light to find its way out, the colour of the light being modified by funnels or globes of ruby glass, or shades of ruby, orange, or yellow paper or cloth. The gas and oil lamps are much to be preferred to the candle arrangements, as with the former it is possible to raise or lower the light at will. All, then, that the photographer has to do, is to find some small room or closet, which he can make quite dark, in which he can have a plain deal table to work upon, and to purchase a "dark-room lamp" from a photographic apparatus dealer. The description of dark rooms will not, however, be complete unless something is said about the fitting up of a permanent photographic room, in which all the operations, including the manufacture of the plates, may be conducted. On page 25 is given a sketch of such a room ; but before giving some details about it, I think it well to say a word or two on the actual amount of light admissible to the dark room. If the plates that we have to use were absolutely insensitive to red, orange, and yellow light, and if there were no difficulty in selecting coloured mediums that passed only the light of one part of the spectrum, there would be no difficulty in arranging a so-called "dark room" that might, nevertheless, have an indefinite amount THE DARK ROOM. 23 of a certain coloured light ; but the two facts come in, that modern dry plates are more or less sensitive to light of all parts of the spectrum, so that, even if we could select a light representing only a very limited part of the spectrum, we would find it practically impossible to have an absolutely safe light ; but there is also the almost insurmountable difficulty of getting a light that represents only a very limited part of the spectrum. The outcome of all this is, that there is no such thing as an absolutely safe light, and that we should, in all work with dry plates, use no more light than is necessary to enable us thoroughly to see what we are doing. It is quite possible, however, to have a practically safe light that may be quite comfortable to work by when our eyes are accustomed to it, but I would point out to all who are working in the dark-room for the first time, that there is an enormous difference in the esti- mate that we make of the strength of a light, according to whether we come on it first from a brighter or a less bright light. To give an example : If we come from brilliant sunlight into a dark-room that is properly lighted, we see nothing but the lamp or lamps, and these but dimly. If, however, we come into the same room, after having been in the dark, of an even- ing, for an hour or two, it will appear so bright that one can scarcely believe that it is the same room as was seen before lighted in the same way ; every article in it is distinctly visible, and it may even be possible to read a newspaper in it. This is partly due to the contraction of the retina in the bright light, and the expansion in dark, but is much more due to the great loss of sensitiveness that the retina suffers in very bright light. After coming from bright sunlight into a dark-room, it takes from a quarter of an hour to twenty minutes for the full sen- sitiveness of the retina to be regained, and any estimate of the light used for development up to that time is likely to be an under-estimate. Probably few people have gone oftener in and 24 THE DARK ROOM. out of dark-rooms than the writer during the past ten years, yet the extraordinary apparent increase in the light of a dark-room that takes place within about a quarter of an hour of entering it from a very bright light never ceases to astonish him, and even yet he can sometimes scarcely believe that the increase is only apparent. It will be understood then that, if we select the right colour, we can have enough light to be able to see quite easily at those times when the sensitiveness of the retina is at the maximum, but that no light can be safe that will enable us to see at all easily immediately after coming from a very bright light into the dark-room. A sketch of a dark-room suitable to an amateur is given on the next page. D is a window whereby the necessary light is introduced, unless it is decided to use artificial light at all times, in which case the place of the window is taken by a " dark-room lamp," which should have as large a surface for diffusing the light as possible. The window should be about two feet long, by one foot six inches high. It may be glazed in any of several ways. The following will be found to give a good, and, at the same time, a safe (as qualified above) light. A sheet of orange stained glass is used, and between this and the operator a sheet of " canary medium" — a light yellow paper — is fixed. A movable screen of orange paper should be so arranged that it may be brought down to cover the window when the light is very intense, or when the process of plate manufacture goes on. It greatly facilitates working if a movable shade be so arranged that it may be brought between the window and the eyes of the operator whilst still letting the light fall on the plate, and permitting the operator to see the latter. A is a sink made of glazed stoneware. The top edge should be about two feet six inches, or two feet eight inches, above the floor. THE DAKK ROOM. 25 B is the operating table. It should be covered with sheet lead, should have a very narrow and low ridge round all the sides except that next to the sink, should have a very slight inclination in that direction, and should have the sheet lead " dressed " over the edge of the sink, so that all spillings may find their way into the last-mentioned. C is a narrow shelf about four inches above the level of the table and sink, and extending along the whole length of both of them. On it may be placed the lamp when artificial light is used, as when working at night, and the bottles of solutions S C ALE OF FEET (OF* actually used for the development. The lower edge of I the window should be an inch or two above this shelf. There should be a shelf about six inches below the operating-table, on which the flat developing dishes may be kept. E is a table on which the levelling slab may be placed when the manufacture of plates is begun. Above it — or, in fact 2G THE DARK ROOM. along all available space of the walls — shelves may be fixed for carrying bottles, &c. A space is reserved at F for the drying-cupboard, used in manufacturing plates. Above this latter, and with its lowest edge about three feet higher than the floor, should be fixed an ordinary cupboard, with a door closing light-tight. In this may be placed plates or anything sensitive to light, which would be destroyed if left about ; for, as has already been explained, any kind of light will in time act upon the sensitive plate. G is an arrangement of double doors whereby the photo- grapher may go out or in without letting any light enter. If there be not space for this arrangement, one door may be used, with an opaque curtain a foot wider than this door hung inside it. Provision must be made for ventilating the room without letting in light. There should be at least one common gas jet for lighting up the room when no sensitive plates are about, so that solutions, &c, may be mixed with comfort, and there should be provision made for attaching several rubber tubes with the gas-pipes for connecting with Bunsen burners, &c. The photographer will in all probability not build a room, but will adapt one already built to his purposes. In this case he will have to exert his ingenuity to allot his space to the best advantage. I have enumerated all the appliances for which room ought to be reserved. CHAPTER IV. EXPOSURE OF THE PLATE. Befoke giving instructions in the actual manipulations of deve- loping a plate, it is right to define the terms negative, exposure, and development. A negative may be said to be a pictorial representation which, on looking through it at a bright light, shows all the shades, which are seen in any represented object, reversed. Thus, when we look through a negative of a landscape, holding it between us and (say) a gas-light, we see the sky and all objects which are in reality brightest, represented as black ; whilst the darker parts of the landscape are represented by the bare and transparent glass. If the negative be a portrait, we see the face black, looking like a negro's, whilst a black coat looks white, and so on. The negative is produced by the action of light in the camera, the places where the light has acted most strongly being turned black. The time during which it is necessary for the light to act on the plate to produce the required effect is called the exposure. Now, it has been ex- plained that the light acts upon the plate and darkens certain portions of it, but it must be understood that this action is not at first visible. A marvellously short exposure is sufficient to impress on a plate all the details of a landscape in such a manner that, by afterwards acting upon the plate with certain chemicals, 28 EXPOSURE OF THE PLATE. these details may be made risible. This operation is called development, and consists essentially in the increasing of the strength of a negative so faint as to be invisible to the eye, till it becomes as vigorous as we wish. Anyone, however, uncon- versant with photographic operations, will see that when once we have obtained a reverse picture, such as we have described, we have nothing to do but to place this in contact with a sen- sitive film, and allow light to act through the negative, when we shall get a picture with its shades true to nature. The latter process is usually gone through with sensitive paper, and is termed printing. Upon correct exposure and development, nine-tenths of the technical success of negative-making depends ; and when once the student has thoroughly mastered the relation of the one to the other, half the battle will be over. He cannot do so without practice ; but I hope to give him such assistance in explaining the matter as may lead him to the desired end as quickly as possible. Let the beginner select an object upon which he will make his first attempt. If he can resist the temptation to try a por- trait, so much the better. A brightly -lighted landscape, with strong contrasts of light and shade, is the best ; it need not be picturesque. A suitable view can generally be got out of some window, or a very suitable subject is a bust or statue placed either in a well- lighted room or out of doors. We shall suppose, in the present instance, that the landscape is selected. The camera should point neither towards nor away from the sun. If the sun shine direct into the lens, the plate would be destroyed ; if the sun be directly at the back of the camera, the picture will look " flat." Before beginning operations, I wish to explain what is the meaning of correct exposure. Let the student look attentively at the view which he has selected to make his first attempt EXPOSURE OF THE PLATE. 29 upon. He will see that, apart from the various colours repre- sented, there is a very great variety of light and shade. He knows that this range is brought about by the fact that different objects reflect different amounts of light to his eye. Probably the sky will reflect the most light, and going through the whole range from this, he will see that there are a few little bits of the landscape that appear absolutely black. They do reflect some light, but it is so little that, by contrast with the brighter objects, they appear to reflect none. Now let the student con- sider the process that goes on during exposure. He knows that when he has his camera with a dry plate in position, and when he has removed the cap of the lens, a perfect picture of the landscape, with all the shades of light, will be thrown on the sensitive film, and that the light will be acting upon it. It is evident the brighter parts of the picture will first take effect, and afterwards the darker, until the exposure has been pro- longed to such a period that all the shades of light, except those which, as we explained, appear in the landscape abso- lutely black, will have impressed themselves. At this point the correct exposure has been given. Had a shorter time been allowed, some of the darker shades — or, as they are technically called, the detail in the shadows — would have failed to impress themselves, and the resulting negative would have been said to be under-exposed. On the other hand, had the exposure been prolonged, the light emanating from the apparently black parts of the landscape would have impressed the plate, which would eventually appear to be darkened all over, and would be said to be fogged from over-exposure. It is said of a correctly-exposed negative, that it shows all the details in the shadows without being fogged ; if it be correctly developed, there is added to this a just gradation of density. Now we pass on to the practical exposure of a plate, and I shall endeavour to show the student how he can tell, by the 30 EXPOSURE OF THE PLATE. behaviour of the plate during development, whether he has hit the much-desired correct exposure or not. He will need to light his dark-room lamp, and to get by him the three flat dishes, the two measuring glasses, all the stock solutions for the mixing of which directions were given in a former chapter, and his box of dry plates. Now he places his camera in position, opposite the view to be photographed ; he removes the cap from the lens, and places his head under the focussing-cloth. He removes all stops from the lens, if it has movable stops, or, if the stops be rotary, turns them till the largest one is in use. This will make the image on the ground glass comparatively bright, and, by turning the focussing-screw first one way, then the other, he will easily find in what position the image is the sharpest. When he has discovered this, he places the smallest stop in the lens. I say the smallest stop, not because it is necessarily the best for the picture which he is going to take, but because it will enable him to give a comparatively long exposure, which is a convenience, at first at least. Having his camera fixed and focussed, let him place the cap on the lens once more, and retire to the dark room to fill a slide. "When once here, he places the dark slide open in front of the lamp. Now he lowers the light till there is only just enough to enable him to see distinctly.* He opens his plate-box and takes out two plates — two glasses must be placed in the dark slide at once, but one may be a " dummy " if he happen to have but one dry plate ; that is, either a clean plate of glass or a spoilt negative. In placing the plates in the slide, he must be very careful that in each case the side of the plate which appears * Note what was said in the last chapter about the effect of coming from a bright light into the dark room. It will generally be found best to place the plate in the slide lefore going out to focus. EXPOSURE OF THE PLATE. 31 dull, on account of its having the sensitive film on it, is placed towards the outside. Now, having closed his dark slide and wrapped his plates up again, the photographer returns to the camera. He should carry the dark slide under the focussing cloth, for additional security against light ; and in placing the slide in the camera and during exposure should keep the whole apparatus, with the exception of the lens, under the cloth for the same reason. He removes the focussing screen, and places the dark slide in the position occupied by it, keeping the side marked " 1 " towards the lens. He now withdraws the sliding door, which is the only thing intervening between the lens and the sensitive plate. He takes his watch in his hand, and removes the cap from the lens for (say) five seconds, replaces it, slides in the shutter of the dark slide, and carries the latter off to the dark room. I have supposed any of the usual view lenses to be used, the landscape to be brightly lighted, the time of year to be spring or summer, the time of day morning or noon, and the plates to be of " ordinary " rapidity. CHAPTER V, FIRST LESSON IN DEVELOPMENT. In the last chapter the photographer was left at that stage where he had accomplished the exposure of a plate, and was about to begin the development. It should be explained that the developer with which he is going to make his first experi- ment is that known as " alkaline pyro." In the earlier editions of this book, I advised the beginner to make his first experiments in development with " ferrous oxalate," on account of its comparative simplicity. I now, how- ever, consider that, on account of the introduction of sulphite of soda and alkaline carbonates in connection with pyrogallic acid, what is known as the 4 ' alkaline developer " is the simplest of any. A description of ferrous oxalate development is given in a future chapter. The photographer has now, let us suppose, returned to his dark room. He may lay his dark slide, still wrapped in the cloth, on a shelf, and, turning up the white light, make the following preparations. He lays the three flat dishes in a row along the front edge of the table, the one to the left opposite the red light, the others to the right of this one. I shall call the dishes Nos, 1, 2, and 3, beginning at the left. Into No. 2 he pours two or three ounces of the alum solution ; into No. 3 about the same quantity of the " fixing " or " hyposulphite " FIKST LESSON IN DEVELOPMENT. solution. Now he takes the four-ounce measuring glass, and measures into it, using the small graduate, 40 to 50 minims of the ten per cent, solution of pyrogallic acid, and about 100 minims of ten per cent, solution of carbonate of potash. He then pours water into the measuring glass up to 2 ounces.* This is now the developer ready for use. Two ounces is per- haps a somewhat extravagant amount to use for a quarter- plate, and, after some practice has been gained, it may be somewhat reduced, but at first it is best to use a good dose. Everything is now ready. The white light must be entirely extinguished, and the red or yellow light lowered as much as possible, till there is just enough to see by. The plate which has been ex- posed must be carefully removed from the dark slide, and laid — film side upwards — in dish No. 1, which is still empty. Now the dish with the plate in it is taken in the left hand, and the measure with the developer in the right. The developer is poured rapidly, but gently, over the plate, the dish being waved or rocked to make the liquid cover any corner which it may incline to avoid, and the whole is placed again in front of the red light, where it is kept in constant gentle motion. And now (if everything has been rightly done) will begin one of the most wonderful of the phenomena of science or nature which man has been given the power to control — a phenomenon which is always new and always beautiful — the " development of the latent image." Let the beginner watch it closely. The plate has no indication of having been acted upon at all before the developer was poured over it. After, perhaps, twenty or thirty seconds there is a slight darkening of some part. When this becomes distinctly visible the light may be somewhat raised, * Ten per cent, solution of pyrogallic acid 3 c.c. Ten per cent, solution of carbonate of potash ... 7 c.c. Water sufficient to make the whole quantity up to... 60 c.c. C 34 FIRST LESSON IN DEVELOPMENT. for the plate has become less easily affected by it.* It will now probably be seen that the brighter parts of the landscape have become quite visible — in negative, be it remembered ; the sky will be represented by blackness. jSow is the time when we can tell whether or not the exposure has been correct. If it has been, the development will progress with beautiful regularity. The bright parts (or high-lights) appear first ; then slowly, but steadily, more and more of the half tones, or less brightly- lighted parts come out ; and at last every object and shade except the deepest shadows have their counterpart in the nega- tive. In other words, the plate should be darkened to a greater or less extent in all parts except those few which represent the part of the landscape which appears to the eye quite black ; and this should come about within a few minutes. If the plate have been under-exposed, it will be longer before the high-lights appear, and soon after they do the action will stop, no more detail coming out, but large patches of the plate re- maining white as before. If, on the other hand, it has been over-exposed, the high-lights will appear a little sooner, and almost immediately afterwards the whole of the plate will be covered with detail, no part remaining white. The final result of incorrect exposure is, with under-exposure, a hard picture with contrasts over-marked, and with deep, * All this intense care about the light used is not absolutely necessary after a little experience has been gained. Most experienced photographers prefer to work with a light sufficiently bright to enable them to see quite easily after they have become accustomed to the dark-room, but keep the developing tray covered with a light wooden or cardboard cover, raising this for a second or two at a time only to observe the progress of develop- ment ; but it is advisable that the beginner, to gain experience, watch the whole process of development, and if this is done, great care must be taken to keep the light as low as will still allow the plate to be distinctly seen. FIRST LESSON IN DEVELOPMENT. 35 heavy shadows, in which none of the detail which is visible to the eye is represented ; with over-exposure, a flat, uninteresting looking production, showing all the detail which there is in the original, but lacking bold contrast of light and shade. Let us suppose the happy medium to have been hit, if not at the first attempt, after a few plates have been exposed. The development is not of necessity finished when, looking on the surface of the plate, all action seems to have ceased. We have still, as a rule, to wait till the " density " is sufficient. A little reflection on the principles involved in the process of printing, which was briefly described in a former chapter, will show that not only is it necessary for the production of a har- monious picture to have all the details which are in the original represented, but in the negatives these must be represented by a certain definite amount of opacity — or, as it is usually called, density. It must be understood, then, that as long as the plate lies in the developer, even after, when looking down upon it, all action seems to have stopped, the density continues to increase. We may say at once that the most difficult thing of all to judge of in gelatine dry plate work is when the required density is gained. So difficult is this, that even the most experienced photographer may occasionally fail. The reason of this is that the after processes very much modify the apparent density of the negative, and not only that, but in every different make of plate the apparent density is modified to a different degree. We must make it appear far denser than it is eventu- ally to be. It is only by experience that knowledge approach- ing to exactness can be gained on this point. When I come to the chapters on printing, I shall explain more fully the charac- teristics of an over-dense, and a "thin" or under-dense nega- tive. Just now I shall merely indicate the manner in which it is usual to judge of the density. The red or yellow light must be turned pretty high. The plate ust be lifted from tha c2 36 FIRST LESSON IN DEVELOPMENT. developer, and held, with the film side towards the ohserver, for a second only, close to the light, and between the light and the photographer. He must rapidly judge whether or not the density is correct. It may be roughly said that, as a rule, the densest parts should appear almost, if not quite, opaque. If they do not, the plate must be returned to the developer. I shall suppose the correct density to have been gained. The time taken with the developer I have given will probably be from three to six minutes. The developer is now poured back into the measure. If used within an hour or so, or any time before the colour has turned a dark brown, one or two more plates may be developed with it. The plate, after development, is rinsed under the tap, being either held in the hand, or left in the flat dish. After this, as much red light may be admitted as is desired. Then the plate is laid for five minutes in the alum solution, to harden the gelatine film. It is again thoroughly rinsed, and is placed in the fixing solution. It will have been observed that up till this time the plate, looked at from the back, still appeared white. This is because the sensitive salt of silver which was not acted upon by light still remained in the film. On placing the plate in the hypo- sulphite, this whiteness will gradually vanish. When there is no further appearance of it from the back, white light may be freely admitted. The plate must still be left a few minutes in the fixing solution, however, after which it must be most thoroughly washed. It should remain at least half an hour either under running water, or in frequent changes of clean water. After that, it is reared upon edge to dry, when the negative is complete. Heat must on no account be used in drying. CHAPTER YL LENSES. Of all the apparatus which the photographer uses, there is none of so great importance as the lens. With a bad camera, shift can be made, and excellent work turned out, the only drawback being more labour and inconvenience for the operator ; but with a bad or unsuitable leos, nothing good can be done. This being the case, it is desirable to give a short description of the various lenses in use, saying for what kind of work each is best suited. Before doing so, however, I will give a few general facts with regard to lenses, and especially I shall lay stress on the manner in which it is possible to compare the rapidity of different lenses. It will be necessary to define a few technical terms continually applied to lenses. The focus — or, more correctly, focal length* — is the distance between that point (generally in the lens) where lines joining points in a distant object and in the image cross each other, and that point on the axis of the lens where parallel rays^of light are brought to converge to a point by the lens. It is commonly * When the focus or focal length is talked of, " equivalent focus " always is meant. The term " back focus," frequently used by opticians, means simply the distance between the back glass of a lens and the ground glass. This distance it is not important to know, except in connection with the adjustment of the lens or the camera. 38 LENSES. spoken of as the " equivalent focus ,f in the case of compound lenses, the meaning being that these lenses give a size of image " equivalent " to that given by a small double convex lens of certain focal length. This is possibly a meaningless definition to the beginner, in which case he need merely bear in mind that for the purpose of determining exposure, sufficient accuracy is gained in the case of a single landscape lens by taking the focus as the distance between the lens and the ground glass ; and in the case of a double combination lens of modern construction, either view or portrait, by taking the distance between the diaphragm and the ground glass, a distant object in each being focussed. In the case of the orthoscopic, and various other forms of lenses, this manner of determination is not sufficiently accurate even for the calculation of exposures ; the following method of determination will, however, give results of sufficient accuracy. In front of the camera is placed a foot-rule, or other convenient object. The distance between the foot-rule and the lens, and that between the lens and the ground glass, are so adjusted that, when in sharp focus, the image on the ground glass is of the same size as the object. The distance from the foot-rule to the ground glass is now measured. This, divided by 4, is the equivalent focal length. Example, — When we draw out a camera till the image on the ground glass is equal in size to the object, we find that the dis- tance from the object to the ground glass is 32 inches. One- quarter of this, or 8 inches, is the equivalent focus. The following method may be adopted when the camera will not rack out to twice the focal length of the lens. It is capable of giving very precise* results, but requires a slight knowledge of algebraical forms. * Not mathematically accurate, but well within the limits required by the photographer. LENSES. 3D d = distance from object to ground glass when a near object is focussed. 0 = length of object focussed (preferably a measuring rod). 1 5= length of the image of this rod on the ground glass. lesser conjugate focus — that is to say, the distance that may be between the optical centre of the lens and the ground glass when a near object is focussed. /= equivalent focus. o + i F_(d-F) J ~ d Example. — A 5-foot rod is focussed. The length of the image on the ground glass is found to be 6 inches. The distance between the rod and the ground glass is found to be 10 feet 1 inch. 6ias. X 10 ft. 1 in. 6 X 121 726 F ~5 ft. 0 in.+ 6 ins. - 60 + 6 ~ 66 ~ U 11(121—11) 1210 f ~ 121 -121- 10 Equivalent focus, therefore, is 10 inches. The aperture of a lens is the diameter of the smallest com- bination forming it, or of whatever stop smaller than this may be in the lens. By full aperture of a lens is meant, in the case of a single achromatic lens, the diameter of the largest stop with which the lens will give good definition in one plane ; that is to say, the diameter of the fixed stop with which the optician fits the lens. In the case of a double combination lens, it is the diameter of the front combination if the two be of equal diameter; of the smaller combination if the two be of unequal diameters ; or, of the fixed stop if such be smaller than either of the com- binations. In the case of a triplet lens, the "full aperture" is 40 LENSES. the diameter of the smallest combination, or of the fixed stop if this be smaller than any of the combinations.* By depth of focus is meant the power in the lens to represent sharply objects both near and far from the lens. The larger the aperture or the longer the focus of the lens, the less the depth of focus. With every lens is supplied a set of stops or dia- phragms. These are simply thin metal plates with holes of larger and smaller sizes in them, that are made to slip in front of or between the combination of a lens. The more depth of focus is needed, the smaller stop must be used, and consequently the slower the lens will be. By width of angle is meant the amount of picture which can be included without complete falling off of definition, or of light, towards the edges of the plate. Let us suppose that a camera with a certain lens is placed opposite a row of houses. It is necessary, to illustrate this point, to suppose the camera to have a very large ground glass, larger than there is any chance that the lens will cover. It may be found that only the central part of the ground glass shows a sharp image, all beyond being " fuzzy," or even quite dark. Possibly two houses are repre- sented correctly. Now let us suppose another lens of different make, but of the same focal length, to be substituted for the first. The two houses which gave a sharp image on the ground glass before, will give a precisely similar image now; but possibly a house on each side of these will also be defined sharply. In this case the latter lens is comparatively a wide- angle one. It must be understood that narrow and wide-angle lenses give images of the exact same scale if the focal lengths be the same ; the latter form of lens takes in a wide-angle, only * The definition of " full aperture M is not strictly correct as described for double and triple combination lenses, but it is accurate enough for all practical purposes. LENSES. 41 on a larger plate, or on the same sized plate only, by using a lens of shorter focal length. Distortion is a fault met with in some photographic lenses. It causes straight lines near the margin of the object to be represented by curved lines in the image. Flatness of field is, roughly speaking, the quality in a lens of having the definition at the edge of the plate good as well as that at the centre. The rapidity does not need to be denned, but I propose to explain the factors regulating it. Every lens is of different rapidity from others of another form, and each lens has a number of diaphragms varying its rapidity, so that at first sight it might appear a difficult task to put a value on the speed of a lens using any particular diaphragm. The law which governs the rapidity of lenses is, however, so very simple that its application is most easy, and I would try to impress upon the beginner that he should thoroughly master it at the beginning of his practice. If he do so he will find the estima- tion of the necessary exposure a comparatively simple matter. In changing one stop for another, or one lens for another, he will have nothing to guess except the intensity of the light. I give, further on, a set of tables which almost entirely do away with the necessity for even this small amount of calcula- tion. The method of comparing lenses — one which applies to all lenses — is as follows. State the ratios between the apertures of the lenses and the focal lengths of the lenses as fractions — the aperture as the numerator, the focal length as the denom- inator. Square the fractions thus obtained, and the resulting figures will give the ratios of the rapidity. It is usual to state the fractions thus: //4, //12, //40. These fractions refer to lenses, the first of which has an aperture one-fourth of the focal length, the second one-twelfth, and the third one-fortieth. We 42 LENSES, shall take a practical example. We are using a portrait lens 10 in. focus, and aperture 2| ins. ; that is, the focal length is four times the aperture, or we may say the lens is working at //4. The focal length, be it remembered, is taken at the distance between the diaphragm and the ground glass. "We now substitute a single lens of 12-inch focus with a stop J- inch in diameter. The aperture is now iV of the focal length. The lens is working at //16. Square these two fractions, thus : — (4) 2 = tV> ("l~6") 8 ~25 "6 • The rapidity of the lenses is as to . The exposure needed will therefore be as 16 to 256, or as 1 to 16. Thus, if we had been giving two seconds with the portrait lens, we should have to give, on the same subject, thirty-two seconds with the single lens. If the beginner will exercise himself in this rule for a little time, he will find that he soon gains great facility in applying it, and that it gives him a ready power in estimating the necessary length of exposure. With the same lens and different stops, the rapidity varies as the square of the diameter of the stop, or as the area of the stop. I shall now rapidly describe different kinds of lenses most in use, giving the purposes for which each particular form is best adapted. We have first The Single Lens. It is the simplest form of lens, and is in many respects excel- lent. It is fairly rapid, especially in some of the new "long focus" forms, includes all the angle that is desirable for general work, and gives wonderful definition, whilst it is the least expensive form of lens made. Its only drawback is that it gives slight distortion. If, for example, it is attempted to photograph a building with it, nearly the whole plate being covered, the boundary lines will appear slightly curved, and the building will seem somewhat barrel-shaped. This distortion LENSES. 43 is, however, barely perceptible if the focal kngth oi the lens be at least 1| times the length of the plate, and, if the beginner cannot well afford to buy the " rapid rectilinear," he will find that he can do excellent work with the " single achromatic. " The next cut shows Dallmeyer's new rectilinear landscape lens. As indicated by the title, the peculiarity of this lens is 44 LENSES. that it does not give the distortion mentioned above. The writer has found it an excellent lens in practice, giving great evenness of definition over the size of plate it is intended to cover, but he does not consider that it possesses the peculiar characteristic of the " single lens," which is the existence of only two tl reflecting surfaces." The rectilinear landscape lens has four reflecting surfaces — the same number, that is to say, as most other rectilinear lenses. By a mistake this cut shows the lens as if it were fitted with rotary diaphragms. Asa matter of fact, it is fitted with Water- house diaphragms. The Kapid Rectilinear or Rapid Symmetrical is one of the most useful of lenses. It is very rapid, and one should be purchased when the photographer has so far advanced as to wish to attempt instantaneous effects. It gives no distortions, and includes about the same angle as the single lens. The Symmetrical or Wide- Angle Rectilinear is a somewhat slow lens, but takes in a wonderfully wide angle, LENSES. 45 so that it is useful for photographing objects when it is im- possible to get the camera far enough away from them to use the rapid rectilinear. It is quite free from distortion. The Portrait Lens is intended for portraiture pure and simple. The utmost ingenuity has been spent in the case of this lens to get the 46 LENSES. greatest possible rapidity, but many other good qualities have been sacrificed. Thus the field is round, the marginal definition bad, and there is very little depth of focus. For its own par- ticular purpose it was, however, in the days of wet plates, admir- ably adapted. With the very rapid plates that can now be had, it is quite possible to take portraits even indoors with the rapid rectilinear or the single lens, and we do not advise the beginner to purchase a portrait lens. This is particularly true since the introduction of several forms of lens of the rapid rectilinear type, working at twice the aperture of //8, which used to be the standard aperture for such lenses. The newer forms of rapid rectilinear need only about twice the exposure needed with the portrait lens. This cut shows Dallmeyer's " diffusion of focus " lens. The object of the arrangement may be thus described. The ordinary portrait lens defines one plane with intense sharpness, but, on account of want of depth of focus, defines all others but poorly, and the want of definition in these other planes is made pain- fully conspicuous by the extremely sharp definition in one. To overcome this difficulty, the lens we illustrate above has an arrangement whereby, unscrewing the back cell of the posterior combination, the definition even in the best defined plane is somewhat softened, whereby the painful contrast of very sharp definition and want of definition mentioned above is avoided. LENSES. 47 The amount of u diffusion " can be varied at the will of the operator. For a single standing figure it may not be wanted at all. The greatest quantity of it is wanted for large heads. There are numerous photographic lenses sold under names different from any of the above, but all of them will be found to be very similar in action, if not in construction, to one or other of the kinds illustrated. As I am entirely avoiding in these pages all historical reference, I do not describe these lenses, which have now almost gone out of use, and are not manufactured ; but 1 may mention the " orthoscopies 9 " orthographic,' ' "wide- angle doublet/ 7 "instantaneous doublet," and " triplet" lenses as instruments to be occasionally met with, and which, if not quite so good as our more modern instruments, nevertheless possess excellent qualities. DlFFEBENT FOBHS OF DlAPHElOMS. The older form of the diaphragm consisted in a circular metal plate with a hole in the middle of it. At the present time there are used three different kinds of diaphragm described below. The object of the diaphragm is the same in every case, but one form is found more convenient with one form of lens, another with another. The Waterhouse Diaphragm. — Each such diaphragm consists of a plate of metal that can slide into a slit in the mount of the lens. There must be a set of several such diaphragms, and they are generally fitted in a small leather case. These diaphragms being separate, pieces are liable to get lost, or mislaid. They are now commonly used only for lenses of large diameter. The Rotary Diaphragm. — This diaphragm consists in a circular metal plate with a number of circular holes or "aper- tures " in it, so arranged that, by turning the plate on its centre, any one of these apertures may be brought into position. The rotary diaphragm, forming part of the lens, is not liable to 48 LENSES. be misplaced. It is, however, adaptable only to lenses of the slower kinds, whose maximum apertures are small. Indeed, it is commonly fitted only to wide-angle lenses. The Iris Diaphragm has gained much popularity of late, and deservedly. It consists of a series of thin metal sheaths, each centring on a pin, and so arranged that, by either moving a small peg that projects from the lens mount, or rotating a ring that surrounds it, the aperture remaining almost perfectly circular, alters in size as the iris of the eye does on change in the intensity of light. The iris is far the most convenient of all diaphragms. It can be fitted to any, or nearly any, kind of lens. The only objection to it is that it is comparatively expensive.* Since this chapter was written, two great improvements have been made in photographic optics. One consists in the intro- duction of what are known as " Anastigmatic " lenses, the other in the invention of the tele-photographic lens. The necessary limits of a shilling hand-book forbid the writer from illustrating these lenses, or describing them at any great length ; but the following brief descriptiou may be of use to readers. Anastigmatic Lenses take the place, according to their con- struction, of wide-angle rectilinear lenses, rapid rectilinear lenses, or even portrait lenses. Their chief advantage is that they show markedly better marginal definition than any of the older forms of lens. The price is, however, much greater. It is quite a matter of opinion whether, for the work of the amateur, it is worth paying this extra price, as many hold that the older forms of lenses give all the definition, both marginal and otherwise, that is wanted for pictorial work, some even going the length of saying that the slight falling-off of marginal # The whole of the subject treated of in this chapter is much more fully dealt with by the writer in " Optics for Photographers," published by Messrs. Piper & Carter LENSES. 49 definition given by these older forms actually adds to the pic- torial effect. For a great many kinds of special work, such as line work and photographic surveying, there can be no doubt of the vast superiority of the new lenses. Tele-photographic Lenses. — A tele-photographic lens consists of a portrait lens, or a rapid rectilinear, with an attachment that extends into the camera. This attachment holds a " negative element" (or, in popular language, a diminishing lens), which has the effect of giving a much larger image than could otherwise be got with the same extension of the camera, and, moreover, enables the photographer, by adjusting the extension of the camera and the distance between this negative eltment and the other lens, to get, within wide limits, any size of image that he wants. CHAPTER VII. THE MANAGEMENT OF THE CAMERA IN THE FIELD— THE SWING-BACK, RISING FRONT, ETC. If the photographer has diligently perused the preceding chapters, and has gone through the various manipulations described in them, he will now be ready to sally forth into the field, and, selecting the beauty spots of nature, to transcribe them by the aid of his camera and lens. He may, in fact, make pictures. I have declared my intention of not entering into the question of art in connection with photography, but have referred the reader to more advanced works for guidance in this direction. Yet a few general remarks on the subject, made with much diffidence, may not be out of place, especially in indicating those points wherein the requirements for a photographic picture differ from those for a painting. The chief of these arises, of course, from the absence of colour in the former. We cannot have transcribed by the camera the broad contrasts which are frequently brought out by colour alone. "We must trust entirely to form and to light and shade. Yery frequently a scene will make a most perfect picture on the camera ground glass, when the experienced photographer knows it will make nothing in the print. Alas ! the colour which makes the picture cannot be reproduced. MANAGEMENT OF CAMERA IN THE FIELD. 51 This makes it all the more necessary in the case of the camera to have the outline and the shades of light harmonious and well balanced, for on them alone must the picture depend. The picture must not be all on one side, nor yet should it be in each half similar. The most striking object should not, as a rule, be in the centre of the picture, but somewhat to one side or the other, there being an object of secondary interest on the oppo- site side of the picture — but not symmetrically opposite — to balance it. Mr. Norman Macbeth, a painter of much talent, has read various papers before photographic societies, propound- ing the view, that if the space occupied by the landscape be divided horizontally and vertically into five or seven equal portions, the primary and secondary points of interest should fall on the intersections of these lines, but not on bi-laterally symmetrical intersections. To illustrate this, I give a set of B a A. intersecting lines as described. If, now, the primary point of interest be at A, the secondary point of interest must not be at a, but at B. The horizon line should, as a rule, be about one-third or two- fifths of the height of the picture, either from the top or the bottom. There must not be too large patches of either very dark shade or of light without some small portions of the con- trary shade to relieve them. 52 MANAGEMENT OF CAMERA IN THE EIELD. For the rest, there is generally wanting to a perfect land- scape picture — be it painting, drawing, or photograph — a fore- ground, a middle distance, a distance, and a principal object. This latter is generally situated in the foreground or in the middle distance. It is in the distance that photography oftenest fails. What to the eye appears a definite distant landscape — the distance but lending enchantment and softness — comes out in a photograph so dim and faint that it would seem to be almost hidden by a thick mist. The slight haze which, in England at least, generally appears between us and the distance, is exaggerated so as almost to obscure those things which are quite clear to the eye. A certain amount of haze covering the most distant objects in a photographic landscape is, indeed, necessary to give the idea of distance at all, and on the way in which this is managed will depend, more than on anything else, the success or failure of the picture from an artistic point of view. The difficulty is to be found in the fact that the haze actually seen is always greatly exaggerated in the camera. It is, therefore, necessary to allow for the difference between what is seen in nature, and what will be the result in the finished picture. Perhaps the greatest difficulty in landscape photography, however, is that the sky is not, as a rule, rendered at all. An exposure which will suffice to bring out all the detail in a land- scape, is such that the sky will be so over-exposed as to show no trace of cloud, but only an even expanse of white. It is necessary, to get the sky, to make a special exposure, perhaps about one-tenth of that needed for the landscape, and to resort to a " double-printing " process, to be described hereafter.* I shall briefly describe the subjects best suited for the camera. Landscapes having, apart from colour, broad and well-marked * See a description farther on of orthochromatic or isochromatic plates. MANAGEMENT OF CAMERA IN THE FIELD. 53 contrasts of light and shade, and decided outline of form, are specially suitable. Trees of all kinds are well rendered, both with and without their leaves ; in the former case the difficulty is to get them motionless. A quite windless day is necessary, unless the light be so good that the exposure need be only a fraction of a second. Architectural subjects of all kinds are most perfectly reproduced by the camera. The most charming effects of any are, perhaps, produced in a scene in which there is water — a quiet pool with reflections of trees, for instance ; shipping in motion, &c, will be treated of in the chapter on instantaneous work.* Let us suppose some locality has been determined on where the photographer is sure to find subjects such as those which have just been mentioned. I shall describe, as accurately as I can, how he should proceed. Before he leaves home he has to fill his slides. After he has done so, he should draw out each shutter of each slide, and gently dust the surface of the plate * The above is a brief epitome of a set of general principles that have never been taken as absolute rules, but that have been believed to give useful assistance to many photographers who have tried to produce really artistic pictures. Since it was written, there has arisen a school of photo- graphers calling themselves " naturalists," who discard all such rules even as suggestions. Their views are represented — or rather, perhaps, it would be more correct to say they arose from — a book entitled " Naturalistic Photography/' written by Dr. P. H. Emerson . [Dr. Emerson having recanted all that he taught in this book, it is difficult to know what to say, but that the discussion that arose from it, and the attention that it drew to the artistic side of photography, has done much good.] This book should certainly be read by all photographers. It displays much originality, and, in spite of what are considered by many to be grave errors, the student cannot but learn much from it — at least, from those parts that treat solely on the art part of the question — and they would certainly learn more if the author had been more tolerant and less dogmatic. Those who wish to gather the views of the older school, which Emerson strongly opposed, should read the works of H. P. Robinson. 54 MANAGEMENT OF CAMERA IN THE FIELD. with a piece of soft cotton-wool, or a camel's hair brush. Let us suppose he has three double slides, they must be packed into a case which should be made to hold them and the camera. Besides these, he must take his lens, his tripod — and let him be most careful not to leave the screw behind him — his focussing cloth, and possibly a " focussing magnifier." This is a small eye-piece to magnify the ground-glass image, and assist him in focussing with precision. It is useful greatly because it increases the light. When a small stop is used, the ground- glass image is often so dull that it can barely be seen. Arrived at the scene of action, the photographer must select his point of view most carefully. Let him be in no hurry ; often a picture will be made or spoiled by changing by a few yards the position of the camera. When he has quite made up his mind, let him unfold his camera, erect it, and place it before the scene to be depicted. A few words on the management of the tripod stand. With the beginner this is apt to prove most wonderful and fearful in its movements. The effect of moving any one leg appears to be the exact opposite of what might have been reasonably expected. After long struggles the whole apparatus assumes an appear- ance of hopeless intoxication, and finally collapses, very pos- sibly pinching severely the tyro's fingers between the tail-board and one leg ; after which frequently follows language not to be repeated by this writer. Let the stand be, however, once for all placed on the ground with its three legs about equally far, and a good distance, apart, and with one of them pointing in the direction of the scene to be photographed, and all trouble will cease. There will be room for the photographer to focus comfortably standing between the two back legs. To tip the camera up, all that is necessary is to draw the forward leg towards him ; to tip it down, he need only push it from him. He may still further tip the camera up by spreading the back MANAGEMENT OF CAMERA IN THE FIELD. 55 legs apart ; and down by bringing them together. He may- turn it slightly to one side or the other by swivelling it on the screw, without moving the stand. When the camera is fixed, and the view is focussed, it will probably be found that there is too much foreground and too little sky. Now, one of two things may be done. The camera may be " tipped " up. In this case, if there be any parallel vertical lines in the picture, they will be made to converge towards the top, and it will be necessary to bring the swing- back into play, as will be shortly described. If there be no vertical parallel lines, the camera may be tipped a little with- out appreciably modifying the result, or the camera front and lens may be raised in the manner to be described hereafter. Most cameras are made so that either a vertical or horizontal picture can be taken, and judgment must be used to determine in which position it shall be. All the points above indicated having been considered, and the picture being all on the ground glass — proceedings so far having been conducted with open aperture or a large stop — the final focussing must be done, and of this final focussing it may be said that it depends on it, next to the selection of the view itself, whether a picture will result or not. Indeed, a quite indefinite amount of skill may be shown in deciding two things, namely, what plane shall be focussed for, and what stop shall be used. It is a question of dispute whether any part of a photograph should be as sharp as a good lens can make it, or not. It is the writer's opinion that, at least, some one part of most photo- graphs should be as well defined as possible, but this is a thing to be decided by each photographer for himself. If it is decided that no part of the photograph is to be quite sharp, either a lens with some spherical aberration — that is to say, a lens that will give nothing quite sharp — must be used, or, after the nearest object in the view has been focussed for, the camera 56 MANAGEMENT OF CAMERA IN THE FIELD. must be racked out a little bit, so that even this will be slightly out of focus. The following hints may be of use. The object in sharpest focus should generally be the nearest object to the camera that is of any interest. Often this will be the object of principal interest. This having been focussed for, it must be decided to what extent other planes are to be made sharp, or left with only partial definition, an affair determined entirely by the diameter of the stop used. If the object of greatest interest be in the middle distance, it may be left a very Utile out of focus. The distance may generally be left quite perceptibly out of focus, although whether this is advisable or not will depend entirely on the nature of the subject. A very small part of the foreground distinctly out of focus will generally spoil a picture altogether. Focussing is commonly done with the full aperture of the lens, but some lenses have a little residual spherical left to give a soft effect in using the full aperture. "With these the focus- sing should not be done with full aperture, unless such is actually to be used. It is a good thing to make it a rule with all lenses but those of the wide-angle type to focus with the stop to be used if it be one of the two or three largest, with a stop about half the diameter of full aperture if a small stop is finally to be inserted. "Whatever effect has been decided on, it is got by inserting smaller and smaller stops, examining the image on the ground glass after the insertion of each. Now all is ready for exposure. Let plate Iso. 1 be exposed first, and on no account let any plate be exposed other than in its order, else the photographer will be likely to expose two views on the same plate. A much more irritating thing he cannot do. In exposing, procedure is exactly as described in a former chapter. There is given further on a set of Tables, from MANAGEMENT OF CAMERA IN THE FIELD. 57 which may be learned, as accurately as it is possible to learn from anything but judgment gained from experience, the exposure which it is necessary to give for different subjects. It may be said that, for a landscape, the most pleasing light- ing is usually a side lighting. The lighting looking towards the sun is sometimes very pleasing, but care must be taken not to include the sun itself. This must be either to one side of or above the picture, or may be kept out of it by the camera being placed in the shadow of a tree or some such object. In the older days of photography it was not considered possible to get good landscape effects but in bright sunshine. There has been a great reaction against this idea lately. Like most re- actions, it has gone too far, some seeming to think that artistic landscape effects are to be got only when the weather is dull, nay, gloomy. This is absurd, but it should always be borne in mind that delightful effects are often to be got when the sun is quite hid by clouds, and even at times when it is raining. The Use of the Rising Front and the Swing -Back. In the case of most cameras, the board in front of the camera which carries the lens is so constructed that it can be raised to a certain extent, the object in raising it being to get in high objects, and to reduce the amount of foreground seen, which is usually too great when the camera is placed horizontally and the lens is not raised. Many cameras are, as has already been mentioned, fitted with a swing-back, as well as a rising front. The use of this adjustment needs some consideration, as it is often a stumbling-block to beginners, or even sometimes to experienced photographers. When the subject includes no parallel vertical lines, and when it is seen that it is desirable to take in more of the upper part of it, it is best to tip the camera to a moderate extent. It is not desirable, however, to tip it very much ; so if six or eight degrees 58 MANAGEMENT OF CAMERA IN THE FIELD. off the horizontal do not yet let enough of the top of the subject be taken in, the front carrying the lens should be raised till it include all that is wanted. So much for the case of a pure landscape subject, in which there are naturally no quite parallel vertical lines. In the case, on the other hand, of architectural subjects, it must be taken as an absolute law, that if it is wished to have the vertical lines of the subject rendered as parallel lines in the photograph, the ground-glass of the camera must be kept vertical, whether this object be attained by keeping the camera horizontal and raising the front, or by tipping the camera up and swinging the back, so that the latter returns to the vertical. It may be said that, so far as it is possible to do so, the desired result should be brought about by raising the lens, as the latter is thereby less " strained," so to speak, than when the camera is tipped and the back is swung. What is meant by saying that it is less strained, is that its powers are less taxed, so that it is possible to get equally good definition with a larger stop. There are two limits to the amount to which the camera front may be raised : the first is a purely mechanical one, and de- pends on the fact that in all cameras there is only a certain range of rise given ; the second depends on the lens. It is evident that, if a lens will just only cover a plate when it is opposite the centre thereof, and if the lens be then raised, the lower part of the plate, representing the upper part of the sub- ject, must simply remain blank. The lens will not cover it at all. It may be said then that the lens should, for high architec- tural subjects, be raised till one of the two limits mentioned is reached, after which the camera should be tipped, if it is still necessary. It is held by most that vertical lines in architectural subjects should be rendered as absolutely parallel lines on the photo- MANAGEMENT OF CAMERA IN THE FIELD. 59 graph. The writer is of the opinion that a very slight con- vergence towards the top is not only allowable, but desirable, especially when a very high and narrow building is to be photo- graphed. The amount should be very slight, however. It should be borne in mind that to tip the camera does not strain the lens at all, if the back be allowed to remain perpen- dicular to the axis of the lens ; that to raise the lens strains it a little ; that to tip the camera, and then swing the back, strains it very much indeed, necessitating the use of an exceedingly small stop. The use that has just been described of the swing-back is very simple ; but there is another use to which it is frequently put, and this fact, that the swing-back may be used for two totally different, and as may almost appear, opposite purposes, is the reason why it is often such an incomprehensible arrange- ment to the beginner. I shall give a typical case, in which the swing-back is used for the second purpose, when I hope the matter will be quite clear. We have a pure landscape to photograph, in which we wish to take in, to form the bottom of the picture, a piece of fore- ground which is not many feet from the camera. The middle of the picture will be rilled with a portion of ruined wall at some little distance, whilst behind that is to be seen, at a much greater distance, a rugged crag rising nearly to nil the whole picture. Now we know already, that to have a near object in focus involves racking the camera further out than when we focus for a distant object. To have all the three objects mentioned in focus at the same time would necessitate having the ground-glass at different distances from the lens, the bottom nearer than the centre, and the centre nearer than the top. Now it will be evident, after a moment's consideration, that this condition is fulfilled by swinging the back of the crmera away GO MANAGEMENT OF CAMERA IN THE FIELD. from the lens. The only difficulty is to know to what extent we must swing. This is discovered in the following manner by trial and error : — We swing the back to a certain extent, then focus for the centre of the ground-glass. AVe now notice whether the top part — representing the foreground— can be made sharper by racking the lens either a little farther from or a little nearer to the ground-glass. If we have to rack it a little faither away, the back has not been swung enough ; if we have to rack it nearer, it has been swung too much. Some cameras are fitted with a "side swing " as well as a " vertical swing." This is be used precisely as just described, but when one side of the subject is nearer the operator than the other. CHAPTER VIII. INSTANTANEOUS PHOTOGRAPHY AND HAND- CAMERA WORK. Althouge " instantaneous " photography was practised to a certain extent before the advent of gelatine dry plates, the difficulties in the way of success were so great, that only a few of the most skilled ventured to attempt it. Now all is changed. So easy is it to take what are called instantaneous views, that there is no reason why such should not be included among the work even of the beginner. The term instantaneous is a most indefinite one, and one that might with advantage be disused, could a better be found. It means, of course, a very short space of time, and, with regard to photography is, we may state, commonly used to designate an exposure varying from about half a second to a very much briefer period of time — for the subjects which the landscape pho- tographer is likely to attempt, say to the hundredth of a second. Much shorter exposures than these have been used for special purposes, but the results, however curious or scientifically use- ful they may be, can scarcely be called artistic. For most subjects that are capable of forming a picture, exposures from a tenth or a twenty-fifth of a second are suffi- ciently short. Many instruments have been invented, and are sold with the object of making it possible to vary the exposure, and to adjust it to any desired fraction of a second. 62 INSTANTANEOUS PHOTOGRAPHY. It would be too much, probably, to say that any shutter com- pletely fulfils these conditions. The writer has tested the speed of many shutters, and, in the case of those pretending to give definite small fractions, has seldom found that the claim was much more than a fashion of speaking. Farther than this, he has seldom found that shutters claiming to give minute fractions of a second gave exposures as short as they were supposed to. He has found only one shutter — and this for a lens of but small size — that gave an exposure of less than i^th of a second. By far the greater number gave a minimum exposure of from A-th to -oVth. of a second, although many of these were catalogued as giving " exposures or less than a hundredth of a second. " Spite of all this, it must be admitted that there are now many shutters in the market of great ingenuity, exceedingly convenient to handle, and of the highest practical use, the more particularly if the user discount a little from the wonderful things that the makers profess their shutters will do. It would not be fair, where there are so many excellent instruments, to recommend any particular one. I shall merely say that a shutter giving a variable exposure is to be preferred ; that, in the case of compound lenses, there are several advantages in a shutter working between the combinations, and opening and closing at the axis, but that many shutters working in other positions work excellently in practice. Whatever form of shutter is chosen, it should be observed that it allow the lens to be fully open during the greater part of the exposure. This is, as a rule, accomplishable only by having the opening, or openings, that admit light long in the direction in which they move. Shutters with a pneumatic release, in which the exposure is given by pressing a small rubber ball at the end of a flexible rubber tube, are particularly convenient, and nearly all shutters are now made with such an arrangement. As regards the subjects most suitable for instantaneous work, INSTANTANEOUS PHOTOGRAPHY. 63 a few words may be said. Of all sucli, sea scenes come first. Effects of sea and cloud alone often make charming pictures, with the addition of ships in motion even more so ; river scenes are also well rendered. Much more difficult, and usually much less successful as pictures, are subjects including crowds of people. For such, the exposures must be longer, the lens must be used with larger aperture, or the plates must be more sensi- tive than for subjects of the nature of those first mentioned. Nevertheless, many wonderful representations of crowds on the sands of the sea -shore, in the streets, and so forth, and even representations of horse races, with their thousands of eager spectators, have been produced, and, indeed, as the last few years have seen a great increase in the sensitiveness of plates, and, as has already been stated, what practically amounts to a doubling of the rapidity of the lenses available, at least, for small work, the difficulties may have said to have disappeared, unless large work be attempted. It is for this kind of work that the hand-camera is particularly suited. For the shorter exposures mentioned, it is evident that a mechanical instrument is needed. There are many such, but all are classed under the title " instantaneous shutters." For the first object mentioned, however — namely, sea and sky, without moving shipping, or with only such as is in the distance, or is moving but slowly — an instantaneous shutter is by no means necessary, as a comparatively prolonged exposure may be given. It is quite possible to give by hand, with a little practice, using the common cap, an exposure as short as a fourth or a fifth of a second. This is quite short enough for the effects which we are just now considering. The cap is rapidly lifted upwards to an inch or two above the lens, then quickly re- adjusted. It is evident that in this manner a somewhat longer exposure will be given to the sea than to the sky, but this is 64 INSTANTANEOUS PHOTOGRAPHY. an advantage rather than otherwise. It is advisable to use a very loose cap, or even one a size larger than that actually intended for the lens. If ships or boats in rapid motion are to be included in the picture, or if men or animals in motion are to be attempted, an instantaneous shutter giving a short exposure is necessary, the aperture of the lens being increased to a corresponding degree. "When the first edition of this book was written there were but few mechanical shutters, and those were far inferior to the best of the present day. The writer, therefore, recommended a simple drop shutter. There are probably few now who will be satisfied with so primitive an instrument, but, as there may be some who, being mechanically inclined, would like to make a shutter with which excellent work may undoubtedly be done, whose only objection, indeed, for any but very rapid work, is its comparative cumbrousness, the description and cuts from the original edition is retained. The sketches given scarcely need explanation as far as construction is concerned (see next page). A is the dropping piece ; B, of which there are two, is one of the sides forming a frame through which A drops ; C is a dis- tance piece, of which, again, there are two, to keep the two B's apart ; D is a thick piece of wood, in which there is a hole accurately cut to the size of the hood of the lens, so that it may support the shutter. The arrangement is here shown complete. Any hard wood forms a suitable material out of which to con- struct the instrument. The B pieces may, with advantage, be of vulcanite ; A is better of wood. If it is made of vulcanite, considerably greater width than is shown must be allowed at each side of the aperture, or the drop is likely to snap the moving piece in two. The frame should be put together with, glue and screws. And now for the action of the arrangement. Of course it is understood that A slides easily, and without friction, between INSTANTANEOUS PHOTOGRAPHY. 65 the two pieces B. Indeed, it should drop almost without touching them ; a y b, and c f are saw slits through both pieces B. They form a trigger arrangement, and also one whereby it is possible to give a variable exposure. Focussing is done with iB 2. THUS i THICK q 1 0 I. THUS |" THICK the piece A entirely removed from the shutter. This is then inserted, a small piece of cardboard, such as a common calling card, being placed in one of the slits, a, b, or c, so that the dropping piece supports itself on d. If a comparatively long exposure be needed, the card is put into the slit a ; if a short one, in the slit c ; whilst for a medium exposure, b is used. The reason of the variation is not far to seek. The velocity of a falling body is, as we all know, uniformly accelerating. It is evident, then, that if the moving part has been allowed to fall for a certain distance, it will fall more rapidly across D 66 INSTANTANEOUS PHOTOGRAPHY. the aperture than if the exposure "began with the falling. The fall is arrested by the projec- tions e e, coming into contact with those at /. A shutter made to the size given is suitable for a hood 1 J to 1J inches diameter. It will do well for a lens of the rapid sym- metrical or rapid rectilinear type, suitable for plates 6J by 4f , or a little larger. The lengths of the three different exposures given by it are approximately |-, iV> and - 2 \ of second. In the accompanying sketch, showing the shutter complete, g is a piece of blackened tin or ferro- type plate, bent as shown at E, so that it may slide up and down in front of the aperture. By adjusting it, so as to cover a part — say a third — of the upper part of the aperture, the sky is somewhat shaded, without affecting the light the foreground receives, and thus a better result is obtained in certain cases. The lower edge of this shade may, with advan- tage, be cut into serrations like the teeth of a saw. The feature most worthy of notice in the shutter described is the great length of the aperture ot the dropping piece in the direction of it3 motion. This I consider a most necessary thing. It is impossible here to enter in detail into the reasons for so thinking. I will merely point INSTANTANEOUS PHOTOGRAPHY. 67 out that if the moving aperture be only the same length as the diameter of the aperture of the lens, the instrument is, during the whole time of exposure, either opening or closing, and the full force of the light only acts for an infinitely short period. The disadvantage of this does not need to be explained. In the shutter with a long moving aperture, it will be seen that there is the clear aperture of the lens during the greater part of the exposure. The long aperture, and the arrangement for varying the exposure, involve a larger instrument than would otherwise be necessary, but I consider this disadvantage more than compen- sated for in the additional amount of light got. In instantaneous photography the camera is manipulated as for ordinary landscape work up to the time when the exposure is to be made. The instantaneous shutter is then adjusted. The shutters of the dark slide must not be withdrawn till as nearly as possible before the exposure is made. The effect desired is watched for. Nervousness and hurry must be avoided, though it is difficult. It is much more common to expose just too soon, than just too late. When the exact moment has arrived, the shutter is put in motion, and the plate receives the actinic impression. Hand-Cameka Woek. The hand-camera has already been mentioned. The writer has expressed his opinion that it is not an instrument to put into the hands of a beginner ; but any book of the present day, professing to treat of even elementary photography, would be incomplete without some mention of hand-cameras. The advantage of the hand- camera is that groups are taken without their attention being attracted, and that thus a natural effect is got no to be had in any other way. It would be out of place to recommend any particular kindTf d2 68 INSTANTANEOUS PHOTOGHAPHY. camera here, and, indeed, I do not intend even to decide for the reader whether he should use films or plates ; if the latter, whether he should use a magazine camera, a camera with a changing box, or with a set of dark slides. He should consult a general dealer in photographic apparatus on these matters, or should see what kind of work his friends are doing with hand- cameras, and choose accordingly. A few general hints only can be given here. First, as to the external form of the camera. There is no need to go in for elaborate concealment of the fact that the apparatus is a camera. The attention of people is not so easily attracted as might be supposed. The writer has done nearly all his hand-camera work with an ordinary quarter-plate camera, not concealed in any way, and can remember of only two cases in which his pictures were spoiled by the fact that the attention of the subjects had been attracted. As to size next. This must, of course, be a matter of opinion. The writer considers quarter-plate (4 J by 3J) to be far the best size. Anything under that size he considers not worth pro- ducing, whilst if the size of the camera be greater, the difficulties in the way of lack of depth of focus, and so on, increase greatly. A 5 by 4 may, however, be worked with success. The most important item of the outfit is, it need scarcely be said, the lens. There can be very little doubt as to the best form. It is a lens of the extra rapid rectilinear kind already mentioned, working at between //5 and //6. The focal length is a matter of great importance, nearly all hand- cameras being fitted with lenses of too short focus. The focus of the lens should be from 1 J to 1 J times the length of the plate. Thus, for a quarter-plate, a lens of about six inches focus should be used. The lens should be fitted with either a rctary or an iris diaphragm. One thing should be borne in mind in connection with the lens, and that is, that the depth of focus is absolutely 1 NSTAN r A SEO US P1IOTOG RA PII Y. 69 fixed by the foal length and aperture, so that, if we hear anyone talking of a certain lem as having greater depth of focus than another of the same aperture and focal length, we may be sure he is speaking in ignorance. In the case, however, of lenses of what are called " fixed focus' ' — that is to say, where there is no adjustment for focussing — the apparent depth of focus may vary greatly according to the way in which the lens is adjusted. The proper way in which to adjust such a lens is as follows : — A distant object is sharply focussed for, and then the lens is moved outwards till this distant object is just perceptibly out of focus. The lens is then fixed in its position. If the adjustment be made in this way, an object in the foreground will be sharp at just half the distance it will if the lens be absolutely adjusted for a distant object. Lenses of fixed focus are, however, applicable only to very small sizes — much smaller than quarter- plate — so that, if the latter size be adopted, a focussing arrangement is essential. The shutter of the lens must be rapider than is generally needed for a camera to be used on a tripod. The reason is that a very slight motion of the hand holding the camera makes ao much blurring of the image as a very large motion of any of th*> subjects. It is difficult to do good hand-camera work with an exposure of more than about -roth of a second. A finder is almost essential for a hand-camera. Most have two, one for horizontal pictures, the other for vertical. The objection to most finders — indeed, to all the writer knows of — is that they necessitate the holding of the camera too low. Tor by far the greater part of hand-camera work, the level of the eye is the proper one from which to expose. If a hand-camera be held under the arm or against the breast, the picture got is not that seen in looking at the objects, but is a different one. It may be said that the picture, as it will be photographed, is seen in the finder. This is true, but the scale is generally too small 70 INSTANTANEOUS PHOTOGRAPHY". to enable the composition to be judged of. If pictures are to be taken by the hand- cam era from a low point of view, the photo- grapher should stoop down and still expose from the level of the eye. I hope some day to see a hand-camera so constructed that the image on the finder is visible whilst the camera is held on a level with the eye. The mere operation of exposing by the hand-camera, apart from anything else, is one that needs much practice. The commonest subjects are street scenes, including, of course, houses. The fact that the camera must be held horizontally, otherwise the vertical lines will not be parallel, itself introduces a difficulty when the exposure must often be made on the spur of the moment so as to catch a certain effect. CHAPTER IX. PORTRAITURE. To make portraits — to secure likenesses of his friends — is sure to be an early ambition of the photographer. In fact, he will show self-denial above the average in foregoing his natural desire if his first attempt be not to u perpetrate a portrait." Nor is this to be wondered at, for, indeed, there is a charm in portraying the human face and form, quite other and much greater than there is in making pictures, ever so truthful and beautiful, of stones, and trees, and things without life. Nor need the amateur despair, now that he has at his command the wonderful powers of the dry plate, of reaching a certain pro- ficiency. True, in this department of photography he need not, unless he have very exceptional ability and much perse- verance, as in landscape work, aspire to compete with the pro- fessional, other than the third or fourth-rate one ; still a por- trait done by a friend is sometimes looked upon in a kindly spirit by the original, and valued for the sake of the portrayer. In one point the amateur has an advantage : the surroundings and operations are not likely to create the awe and nervousness that appear to overcome some sitters whenever they enter the formidable studio of the professional. Portraits may be done either out-of-doors or in an ordinary room. I put on one side the possibility of the amateur having command of a studio. 72 PORTRAITURE. Out-of-door portraiture calls for little remark. It is com- paratively easy ; but the results gained are not usually so pleasing as those of successful in-door work. All that is necessary is to get a suitable place in which to operate. There must be some means of shutting off a portion of the top light. This may often be secured by taking advan- tage of the outspreading branches of a tree. The position chosen must be such that there will be a somewhat stronger light on one side of the sitter than on the other ; by this mean 5 * there are secured relief and roundness. If a full-length sitting or standing figure be attempted, a natural background, such as an ivy-covered wall, the stem of a large tree, or such like, is the best. If heads be done, an artificial background, such as will be described hereafter, should generally be used. The requirements for portraiture indoors are more complex. The chief of these is a head-rest. This is an instrument much abused by many; and, indeed, one that it would be good to do away with, but which, in the present condition of photographic knowledge, is still, in many cases, a necessity. The average sitter is unable to keep sufficiently steady without a rest for his head, and for his body if he be standing, during an exposure of longer than four or five seconds. Now, on consulting the Tables given further on, it will be seen that in a common room an exposure so short as this is secured only with the rapider forms of portrait lenses used with full aperture.* If a larger size than the carte, or at the most the cabinet, be attempted, it will generally be found that so large apertures cannot be used, even if the lenses be at hand, because the depth of focus given thereby is so small. As regards lens, that known as the group, or D lens, or one of the extra rapid symmetrical or rapid * Since this was written, the sensitiveness of plates has been so much increased that, by using the rapider brands, the head -rest can generally be dispensed with, even in an ordinary room. PORTRAITURE. 73 rectilinear, is most suitable, unless the amateur possess a portrait combination. In any case, the portrait lens is not to be recom- mended for sizes much above cabinet, as the depth of focus for larger sizes is so very small. For sizes above 10 by 8, even the extra rapid rectilinear is seldom available, and the ordinary u rapid rectilinear 99 is to be commended. Even the "single lens" may be used if the aperture be increased to "8," an aperture at which many single lenses will work (see Tables, pages 86, 87, 88) ; but the exposure will be somewhat pro- longed. One thing is to be particularly mentioned in connection with the lens used for portraiture, either indoors or out : it should be one of long focus, otherwise the most unpleasant effects of exaggerated feet, hands (or in large heads, nose) — in fact, all the parts nearest the camera — will be the result. The focal length of the lens should be not less than about double the larger dimension of the portrait to be produced. Thus, for a carte, it should not be less than 7 J ; for a cabinet, not less than 12 inches. If this rule be observed, the distortion given by single lenses will be quite inappreciable. A background of some sort is a necessity. Sometimes the walls of a room are suitable ; but generally it is best to make a special background. This may be done by making a light frame-work of wood, 7 feet by 5 feet, and stretching on it the coarse brown paper known as " carpet paper." This is done by damping the paper, so as to stretch it, then gluing it on the frame by the edges. Paper may be thus stretched with advan- tage on both sides of the frame ; one side may be left the natural colour of the paper, and will do for dark backgrounds ; the other may be painted of alight grey colour with "distemper," and will serve as a light background for heads to be " vig- netted." The amateur who has the necessary artistic taste and 74 PORTRAITURE. knowledge may produce scenic backgrounds to his heart's content. These are painted roughly in neutral distemper colours. A reflector is a necessity for indoor portraiture. Its use is to relieve the heavy shadows on the side of the face that is away from the light. A sheet or table-cloth, held by an assistant; is sufficient ; but a wooden frame, similar to the background, covered with white paper, is the most convenient. The pose and lighting of the model are, of course, the chief points to which attention must be given. With regard to the first, the beginner should study well the pictures of good artists, both painters and photographers. One thing only I shall say on the matter. The so-common impression, that what the sitter is pleased to consider a free-and-easy pose will give a good result, is generally the greatest mistake possible. Nearly all photographic portraits in which there is an appearance of ease arid unconstraint are the result, not of chance, but of study and intention on the part of an artistic operator. The object to be attained in lighting is softness and round- ness, avoiding on the one hand flatness, on the other harshness, such as is given if one side of the face be in too deep shadow — and to combine with this the maximum of brightness com- patible with it. I shall explain how this may be obtained in any ordinary room. A sketch is here given of a room (page 75), 20 feet by 12 feet, this being a not uncommon size. At A and E are windows, each 3 feet 6 inches wide. Let us suppose the window B is closed by drawn blinds or curtains, or by closing the shutters; it is worth while noticing the various phases of lighting ttat may be brought about by changing the position of It ftitter. Let an obseiver stand at C, the sitter being placed iX E, and the reflector being used. It will be found that an excellent lighting, as regards quality, can be obtained, but that the quantity is so small that the exposure would be extravagantly long. Now let the sitter PORTRAITURE. 75 7G FORTRAIT UIIE. there is too deep shade in the far side of the face, and this will be even more apparent in a photograph than to the eye. A compromise must evidently be made. This may be done by placing the sitter at F. It will now be found that the lighting will be all that can be desired, whilst the exposure will not be much greater than with the model at D. The spot where a soft and harmonious lighting is secured being determined, the next question is, from what direction is the portrait to be taken ? For pleasing results may be got with anything between three-quarter light, one-quarter shadow, and one-quarter light, three-quarter shadow, the latter style of lighting having been given the name of " Rembrandt," although the name is a bad one, as Rembrandt used lighting of every kind. With a room of the shape and size shown, the choice is not great for full-length standing figures, as the camera will have to be kept far from the sitter, and towards the end of the room. "With heads, however — in which particular form of portrait the lighting is, if possible, more all-important than in any other — the camera may have its position varied anything from H to K. Probably the most successful results will be got from H. If the position be approached to K with the object of getting " Rembrandt " effects, means must be taken to shade the direct light from the windbw off the lens. The background, L, and the reflector, M, are shown in positiun for a sitter at F, and for the camera about H. It is unnecessaiy to say that the reflector must be kept far enough away not to appear in the picture. It should, however, short of this, be kept as near as possible. After posing, the head-rest should be adjusted. It must be distinctly understood that this appliance is not meant as a means of clamping up the model's head, but that it is intended as a rest to be brought into position after posing has been performed, so that the sitter may gently lean his head against it. PORTRAITURE. 77 The reason for advising that one of the windows be closed is, that a double source of light is objectionable. It is liable to produce an unpleasant lighting in general, and almost always causes a false light in the eyes. With regard to the taking of groups, my advice is to follow- as closely as possible that given by Punch to young men about to marry — " Don't." An amateur seldom acquires the skill necessary to enable him to pose and light artistically one figure with any degree of certainty. It is enormously more clicfnult when there are several. If groups must be done, they are best done out-of-doors. Except for carte size, a lens with compara- tively small aperture must be used for groups, so as to get all the figures in focus. This makes the exposure very prolonged in an ordinary room. Moreover, some of the figures must, in such a case, be much nearer the light than others. In grouping out-of-doors, the figures near each end of the group should be brought somewhat nearer the camera than the others, as this will bring them into better focus. Several may, with advantage, sit down slightly in advance of those standing. If the photographer can prevent all the members of the group from gazing into the camera with a glassy stare, and cause them to turn towards each other as if in conversation, he will have accomplished much. CHAPTER X. TABLES TO FACILITATE JUDGMENT OF EXPOSURE.* I gave, in the chapter on lenses, rules whereby it is possible to compare the rapidity of various lenses, and, having once deter- mined for a certain subject the exposure for any one lens and stop, to estimate exactly what would be the exposure with any other lens and stop. The work involved is little and easy, but * Violent objection has been made to these Tables by several photo- graphers of great experience and of long practice, but I retain them nevertheless. These photographers of long experience seem to think that nothing that was not of use to them at the time they learned photography — because it did not exist, or for some other reason — cannot be of use to beginners of the present day. I have, however, had so many letters describing the use that the Tables have been to the writers at that time when anything that can assist the beginner to answer that most difficult ques- tion: — "How long shall I keep the cap off the lens ?" is most welcome ; that, apart altogether from the fact that I composed the first three for my own use, and used them for several years, I am still pursuaded that the Tables are of some use. But I quite willingly admit — and, indeed, would emphasise the statement — that, as soon as the photographer's judgment has so far matured that he feels that he can rely on it alone, he should discard all artificial aids. I think, however, that it will generally be found that this ripening of the judgment in the matter of exposure is a thing that takes years ; and, moreover, I do not find that the judgment of those who scorn such assistance as they can get from the first is by any means more quickly ripened than that of those who are willing to take advantage of it. TABLES TO FACILITATE EXPOSURE. 79 there are some who find even such difficult. For the sake of these I have compiled a set of Tables which, I believe, make it as nearly impossible to find any difficulty in estimating exposures as can be. I shall explain the use of them. The Photographic Society of Great Britain has established a standard of rapidity for lenses. A lens with an aperture one- quarter its focal length (//4) has been taken as the unit, and is called ",1/* A stop of half the area, which will necessitate double the exposure of this latter again, is called "2"; one needing double the exposure of this latter again is called " 4 " ; and so on, 8, 16, 32, 64, 128, 256, this last being about the smallest aperture generally used in practice. Apertures larger than £ the focal length — which are rare — are signified by *5, •25. The latter is, I believe, the largest aperture possible to get in practice. Now, it is evident that if all opticians were to adopt this standard, the estimation of exposures would be much simplified. Every stop would have on it a number signifying the rapidity of the lens when it was in use, and the same number would signify the same rapidity in the case of any lens. Moreover, the effect of using a stop one size smaller than another would always be to double the exposure. Many manufacturing opticians have adopted the suggestion of the Photographic Society, but still a number of lenses in the market have not their stops adjusted in accordance with it. Moreover, at least one optician has adopted the standard sizes for his stops, but numbers them according to some scheme of his own, very different from that recommended by the Photographic Society, so that confusion is but rendered worse confounded. It is often, however, easy to alter stops so as to accord with the standard. To enable any photographer to do so who wishes, a Table is given showing for any focal length of lens what are the diameters to which it is necessary 80 TABLES TO FACILITATE EXPOSURE. to cut the stops. Referring to Table I., we find, for example, that with a lens of 9 inches focal length the aperture u I " will be 2*25 inches, that is, 2 J inches. It is only possible to get such an aperture with a portrait lens, and if the lens in question be not such, we must pass onto " 2 " ; here we find 1 59 inches still only possible with a portrait lens, with some group lenses 7 or with some of the new forms of extra-rapid rectilinears already mentioned. " 4 " we find is 1*2. This is a possible aperture with group lenses, and most modern rapid landscape lenses; the next, U 1," is *80 inches, and is an aperture to be had in all lenses of the rapid rectilinear or rapid symmetrical type. " 16 " is *56 inches, and may be had in " single " lenses, and most wide-angle rectilinears or symmetricals of modern patterns; " 32 " is *40, and may be had in any single lens ; " 64 " is -28 inch ; 128 is -20 inch ; and 256 is -141 inch. In the case of a portrait lens, we should thus make our largest aperture 2 J inches, and call it " 1 v (unless, that is, we were able to get an aperture of 3*18 inch, which we would call *5), and the other 1*95 inches, 1*12, and so on, down as small as we pleased. In the case of a group lens, our largest stop might be 1'59, or rather more than 1J inches. "We would, however, not call this " 1," because it is the first stop of this particular lens in question; but "2," because the aperture is //5*657. In a single lens our largest would probably be •56 inches, and would be marked 16. This gives the diameters to which to cut the movable stops of a lens, but the fixed stop of a lens should never be contracted to agree to one of the standard numbers. It should be left as it is, if it does not agree with a standard number, and should be marked with an odd number got from Table III., as will be explained. For any lens whose focal length is half that of one given in the Table, the apeiture must be divided by two. For one with twice the focal length of any mentioned, they must be multiplied TABLES TO FACILITATE EXPOSURE. 81 by two, for three times by three, and so forth. It is thus possible, by mere reference to the Table I., to cut a set of stops to the standard sizes for any lens. We now take Table II. This needs no great explanation. In it will be found the necessary exposures for most subjects with all standard apertures of the Photographic Society. Table III. is not quite so readily understood. I have explained how to cut a set of stops to the standard sizes for any lens, but it is quite possible that some may not have the inclina- tion to do so, or the means therefor. Eor such this Table is intended. Anyone can, by its use, take any lens, and by merely measuring the stops, say what relation there is between the area of each one, and of such a stop as would form the Great Britain Society's unit. Let us take an example. I suppose once more that we have a portrait lens of 9 inches focal length, and that we do not wish to make a new set of stops, but that we wish to find out for each stop what ratio its area bears to one that would form the unit of the Great Britain Society's standard stops, or, in other words, would measure in diameter one-quarter the focal length of the lens, and would be styled u 1," or //4. Say the full aperture of the lens is 2J inches, and the other stops 2 inches, 1 J-inch, 1-inch, and J-inch. On the Table, opposite 9 inches focus and 2J-inch aperture, we find *81, that is to say, the lens will require an exposure of 81, or about four- fifths of a second, where one working with an aperture " 1," or fJ4 } will take one second. Opposite 2 inches in the same line we find 1*24. With this stop the exposure will be 1*24, or (say) one and a- quarter times as long as with a lens working //4. The figures opposite the other apertures mentioned are 2 28, 5*06, 20 25. With these stops the lens will need exposures 2*28, 5*06, and 20*2 times as long as will a lens working //4, which, as has already beer mentioned, is said to have the aperture " I." 82 TABLES TO FACILITATE EXPOSURE. I shall now* explain the working of Tables III. and II. together, by taking a set of examples. Let us suppose that we have a single landscape lens of 8 inch focus, that the subject we are about to photograph is a landscape with deep shadows and dark foreground, and that the stop which, out of those with which the lens is provided, gives the best result is J-inch diameter. In Table III. we find opposite 8-inch focal length, and under ^ inch aperture, "64." We now turn to Table II. Opposite " 64 " (or //32) we find for landscape with heavy foliage in the foreground 8 seconds. This, therefore, is the exposure which we have to give. Again, suppose the lens and subject the same, but the aper- ture only iVinch. We find in Table III., opposite 8 inches focal length and under -ft-inch, " 114." Now we will not find any such aperture as " 114" in Table II., that number not being one of the standard ones. The nearest we can find is " 128," which is somewhat too large. We find opposite it an exposure for landscape, with heavy foliage in the foreground, 16 seconds. Strictly speaking, we ought to work out a propor- tion sum thus : — 128 : 114 : : 16 seconds : the exposure needed, which we will find to be 14*5 seconds. In practice, of course, there is no need of any such accuracy ; we simply notice that as the aperture is somewhat larger than the standard one, the exposure will therefore be a little shorter. Yet another example. Suppose a "rapid" landscape lens, focus 10 inch, stop ^-inch, to be in use, the subject a portrait out of doors. In Table III. we do not find |-inch among apertures. Let us take the nearest on each side of this — namely, f-inch and 1 inch. We find under f-inch 11*1, under 1 inch 6*25. Now neither of these figures is to be found as a standard aperture in Table II., but lying between them, as |-inch lies between f-inch and 1 inch, is the standard number " 8." It will be quite near enough to take the apeiture as this, and TABLES TO FACILITATE EXPOSURE. 83 to take the exposure which we find opposite it — namely, 1 second. Another thing must be mentioned. In case of portraits, when large heads are done, or in any case where subjects very near the lens have to be taken, the camera has to be drawn out to a considerable distance, possibly several inches. The focal length of tho lens is, in fact, increased for the particular subject. This has to be taken into account in judging of the exposure. We shall take an example of this. Let us suppose a 12-inch focus portrait lens used with an aperture of 2 inches, the subject being a portrait indoors. We find that this aperture is, according to Table III., 2*25 ; the exposure will therefore be somewhat more than that opposite " 2 " in Table II. This, for a portrait indoors, we find to be 6 seconds ; we would therefore require (say) 7 seconds. Let us suppose, however, a head one-third life-size to be attempted. It will be found that the camera has to be extended till the focus is 16 inches. Eef erring to Table III., we find that with a lens of 16 inch focus, 2 inches aperture is equal to standard number " 4," and, referring to Table II., we find that an exposure of 12 seconds will now be needed. Table No. IY. was compiled by Dr. J. A. Scott, who com- municated it to the Dublin Photographic Society. It works in conjunction with Table II. The exposures in Table II. are for the very best light— that is to say, for that of the middle of the day in May, J une, or J uly. Table IV. shows by how much it may be necessary to multiply the exposure given in Table II. for any hour any month of the year. I shall explain the working of these two Tables together. We are about to photograph an open landscape at five o'clock on an August afternoon ; the lens we are using is a single achromatic, and we are working with stop No. 128, or //44*25. 84 TABLES TO FACILITATE EXPOSUKE. In Table No. II. we find in the column headed " open landscape," and in the line beginning 128, two seconds. Now, referring to Table IV., we find in the column headed " April or August " (the exposures being the same for either of these months), and in the line beginning 7 or 5 (that is to say, 7 a.m. or 5 p.m., at both which hours the light is the same), the figure 3. This inean3 that the exposure found in Table II. is to be multiplied by 3. We found in Table IT. 2 seconds— 2 X 3=6 ; therefore, six seconds is the exposure to be given. It must be understood that Table II. is only approximate. Thus plates vary considerably in sensitiveness. The Table exposures will be found suitable for most plates that are sold under 6uch names as " ordinary " or i ' landscape,' 9 whilst the quickest plates commonly met with in the market will need exposures of only from one-third to one-fifth those in the Tables. I have, of late years, occasionally come across plates that would work with one-tenth of the table exposures, but they are quite exceptional. Again as to subject. Very often subjects do not come precisely under the headings given. For example, landscapes most often come somewhere between such as are described in the second and third columns. By an open landscape is meant such a subject as shows broad exposures of sunlight without any deep shadows near the camera. River scenes with trees in the distance, roads and houses without trees, and such like, come under the heading. By the " interiors " is meant such subjects as cathedrals and churches. They need very careful treatment, as there is likely to be a greater range of light than can well be registered by a photographic film. With regard to "portraits in ordinary rooms," I explained that, under the most propitious circumstances, the exposures may be reduced to half those given, which are on the assump- tion of an average-sized window, without houses or trees TABLES TO FACILITATE EXPOSURE. 85 opposite it.* If there be opposite the window anything to obscure much of the sky, the exposure will have to be greatly protracted. No rule can be given for exposures in dull and foggy weather ; but it may be said that they often need to be much more pro- tracted for such than the beginner would at first imagine.-)- On the other hand, there is a certain diffused light when the sun's rays reach the earth after passing through a large area of thin fleecy clouds in which the exposures are remarkably short, often as short, or nearly as short, as with the most brilliant sunshine. * With the rapidest plates, and a very large window, I have known it to be reduced to x \jth or even ^th the figures given. With the modern very rapid plates of the market, the exposures will be about £th those given. t For the convenience of photographers, the Tables, and most of the general information contained in this chapter, have been put into a com- pact form, along with space for notes, in a pocket-book entitled " Burton's Note -Book for Photographers." 9d. and Is. Messrs. Piper and Carter, o, Furnival Street, HolborD. TABLES TO FACILITATE EXPOSURE. 1 11 ins. OS CO co iO I— CM 1 OS CO Oi OS CO OS 00 CM CM r- rH 10 ins. iO 1 1 CO so CM ms CM i—l CO CO CM CO CO CM CM CO i w .2 vO M CO CO t-- co CO CO op Oi lp CM 7* OS CM CM CO rH o CO CM rH i rH to rt C5 CO CO »o> CM CM »o CM rH rH o CO CO *o O CO CM O cm i— » rfi ins. it} CM 1—1 o CM o co o 'O l>- CO 00 CO CO CM CO 00 CO CO Him 00 CO CM rH -H 8 ins. CM co CM CM rH ) - ip vO cp CM lO CM • w J t>- I— CO >o co CM 00 CM CO I— 1 CO CO cp H/t CO CO CO CM CO CO rH rH 7 ins. »o> .CO 1 cm j vO l>- rH CO CM i— 1 00 CM co CO CM CM tO Oi o f—» co c * «5 CO co 1 . co CO CM CO CO T— * CM CO rH rH © Focal Length idard No. •25 CM CO CO rH CM CO TH CO CO CM rH «o CM CO TABLES TO FACILITATE EXPOSURE. saiooy; i.iuu;pj||2 1 P r" 1 I to ? js 1! ««# ! ? s 1 J II ? rH ■? ! I £ I 2 I f, s :s , cs 1 1 S I 8 1 1 ?! *» 1 2 1 1 1 I S s SI 123 ;s Hy 2 S 3 3 § s 2 j J« "V t S T s 8 s | 5! ~* S 1 > 3 CD s s 1 ! « 5' »0 CD j N 00 o 0* 01 U jo 'CO ! ^ o ft ° O K ^ kfl ^ | | | | | — ' Cm co o j May or July | -MM HkN * * 1 § * — Hour of Day. A.M. P.M. 12 1 1 .OI 1 10 or 2 9 or 3 8 or 4 7 or 5 6 or 6 5 or 7 4 or 8 o CHAPTER XL SECOND LESSON IN DEVELOPMENT. In considering the subject of exposure in a former chapter, we assumed that correct exposure is a fixed point, and that any deviation from it would give imperfect results. This is scarcely the case, however, for there is a certain "latitude," which is due to two causes: first, a certain latitude of effect is per- missible. Thus, if the plate be a little under-exposed, there will be somewhat less detail in the resulting picture than is visible to the eye ; but this need not altogether spoil it. Again, if the plate be somewhat over-exposed, the effect will be a slight fog or want of transparency in the shadows of the nega- tive ; but the only result of this will be that what is called a " slow printing" negative is produced. The latitude in effect is not great, however. It may be said that if two seconds be the best exposure, anything between one and a-half and three, or perhaps four, seconds will give good results without modify - the developer. We have, however, a second method of gaining latitude, and this is by means of the treatment with the deve- loping solutions. Thus, with any developer, simply by leaving the plate for a longer or shorter time in the solution, we can compensate to a certain extent for under or over-exposure. It is, however, by varying the proportions of the ingredients of the alkaline developer that we gain the greatest latitude. SECOND LESSON IN DEVELOPMENT. 91 The essentials of this developer are as follows: — First, pyro- gallic acid, or more properly, pyrogallol ; and, second, carbonate of potash, liquid ammonia, or some other alkali. With pyrogallic acid and an alkaline carbonate only in solu- tion, it is quite possible to conduct development ; but a soluble bromide, generally bromide of ammonium or of potassium, is used at times along with these to more completely control the action, and such is indeed essential where ammonia is the alkali used. It is also, now, an almost universal custom to have a certain quantity of sulphite of soda (first introduced' by Mr. Herbert Berkley), or of meta-bisulphite of soda (first intro- duced by Swan) in the developer, as such prevents the rapid darkening by absorption of oxygen from the air, and consequent staining of the negative that is otherwise liable to take place. If the sulphite, or meta-bisulphite, be mixed up with the pyro- gallic acid as recommended in the description of " stock solu- tions V in the beginning of this book, the result is a very con- venient concentrated solution that will keep, ready for use at any time, for several months. The pyrogallic acid is the true developer, and acts very ener- getically when rendered alkaline. The stronger the developer is in pyrogallic acid — up to a certain point, at any rate — the denser or more opaque will be the negative ; and, as a conse- quence, the stronger will be the contrast between light and shade in the resulting print. The carbonate of potash, or other alkali, is used to render the developer alkaline, and the greater the quantity in the solution, the more energetic the action. The effect of increasing the alkali is to shorten greatly the time of development, to increase to a slight extent the amount of detail, and, up to a certain point, to increase the density. A point is reached, however, where the action is so energetic as to reduce or blacken even those parts of the plate which have not been acted on by light, 92 SECOND LESSON IN DEVELOPMENT. and fog is the result. Some plates will stand much more alkali than others. The use of the bromide is to retard development — to make it slower, so that it may be more under control. A developer with carbonate of potash or of soda is comparatively slow, even without any bromide, and the latter is, therefore, not needed in normal circumstances; but with ammonia the action, without any bromide, is so rapid as to be quite beyond control. The result of increasing the bromide is to make the developer much slower, to keep back a little of the detail, and to increase ulti- mate density greatly. The function of the sulphite of soda is merely to prevent discolouration of the solution, and consequent staining of the negative. In moderate quantities it may be said that it is quite neutral as concerns the actual development, but, if used in too great quantity, it tends to reduce the opacity of, or contrast of, the negative. The citric acid given in the stock solution of pyrogallic acid (Chapter II.) is used merely to insure the neu- trality, or rather the non-alkalinity, of the sulphite of soda, a salt which is nominally neutral as sold, but that is very often, as a matter of fact, somewhat alkaline. If it is in this condition, it does not perform its function of preserving the pyrogallic acid solution efficiently. Any of various other acids besides citric acid may be used. A little consideration of what has been said will show that by varying the proportions of the constituents enumerated, we have the power of greatly modifying the resulting negative, and have a power of compensating, to a considerable extent, for error in exposure. This is especially the case for over- exposure. It is true that in the case of under-exposure we can correct, to a certain extent, by using an increased quantity of alkali ; but the fog point is soon reached, and thus it is only slightly that we can correct in this direction. In the case of SECOND LESSON IN DEVELOPMENT. 93 over-exposure, however, it is different ; bromide may be added indefinitely. By using a large quantity of bromide the develop- ment is rendered slow as regards the appearance of detail, but less so as regards the increase of density. It is thus possible to stop the process in the case of an over-exposed plate before the shadows veil over, and yet to have a sufficiently dense negative. It is right, in using any particular make of plates, to use the developer recommended in the lt instructions " ; but it is by no means necessary to mix the " stock solutions " exactly as directed. On analysing any of the sets of stock'solutions given, it will be found that they consist essentially of the chemicals mentioned before, made up in solutions of certain strengths, and nearly always with some preservative — generally sulphite of soda, in the case of the pyrogallic solution — to prevent its turning brown by oxidation. In almost every case there is a most needless complication introduced, which makes consider- able calculation necessary to find what quantity m of each chemical really is in an ounce of the final developer. There can be no simpler plan than to mix all solutions used for deve- lopment so that each shall contain ten per cent, of one of the ingredients ; the mixture of pyro, sulphite of soda, and a little acid being looked on as a ten per cent, solution of pyrogallic acid only. Any developer can then be made up in any proportion without trouble, and that given in any instruc- tions can be used without the intervention of complicated formulae. At the end of the chapter there is given a very use- ful table compiled by Messrs. Lyonel Clark and E. Eerrero, showing at a glance the actual proportions of the ingredients recommended as developers by different plate manufacturers (see pages 98, 99 ; the quantities are given in grains and minims per ounce of developer). To carry out the development of all kinds of plates exposed on all kinds of subjects, it is necessary to have, in addition to 94 SECOND LESSON IN DEVELOPMENT the stock solutions mentioned in Chapter II., only a ten per cent, solution of bromide of potassium. This is made by taking one ounce of bromide of potassium, and making up the quantity to ten ounces with water.*' There is no developer that is suitable for all subjects. Those given in instructions can only be taken as typical. If the photographer expect to excel, he must vary his developer to suit his subject. Thus, when the contrasts in the object to be photographed are very strong — say in the case of an interior with white columns and deep shadows — he must reduce the amount of pyro, or he will have a negative giving a " chalky " print. If the contrasts are naturally weak, as is sometimes the case in open landscape, he must increase the quantity of the pyro, and perhaps add a little bromide. If he know that he has under-exposed, he must increase the alkali. If he know that he has over-exposed, he must increase the bromide. The developer given in Chapter V. is somewhat weaker in alkali than is generally recommended, and is, consequently, rather a slow developer. The slowness is a decided advantage, at least at first. There are many who prefer at all times to use but little alkali, allowing the image to develop very slowly, the reason being that they believe that they thereby get a higher quality of negative in the end. There can be no doubt, how- ever, that with most plates, and when the photographer is certain that his exposure is correct, it is permissible to use considerably more alkali even from the first. The following may be taken as a normal developer for average subjects, when correctly exposed, on most kinds of plates : — Ten per cent, solution of pyrogallic acid ...20 to 25 minims Ten per cent, solution of carbonate of potash 100 „ * Bromide of potassium Water to make up to .. 50 grammes 500 c.c. SECOND LESSON IN DEVELOPMENT. 95 To each ounce of developer Deeded.* The time taken for development with this developer will he only two-thirds or three-quarters of that with the developer given in Chapter V. If, as is generally the case in landscape work — at least, in the case of the first plate developed of a number that have been exposed at the same time — there is uncertainty as to whether the plate has been exposed correctly or not, it is best to begin with a developer very weak in alkali, and to add more after- wards if it appear to be needed. The following is the sort of developer that should be first flowed over a plate when there is uncertainty of the kind mentioned : — Ten per cent, solution of pyrogallic acid ... ... ... ... 20 to 25 minims Ten per cent, solution of carbonate of potash ... ... 30 ,, To each ounce of developer needed. f This is a very slow developer, and even if the plate be much over-exposed, the image will not appear for some time. A little experience will enable the photographer to know, by the length of time ^hich elapses between the time of pouring on the developer and the appearance of the image, and by noticing how the detail begins to come up, whether the plate has been over-exposed, correctly-exposed, or under-exposed. If the ex- posure appears to be correct, ten per cent, solution is added a little at a time (say 20 minims) till the detail is all out. The * Ten per cent, solution of pyrogallic acid 2 c.c. Ten per cent, solution of carbonate of ammonium ... 10 c.c. "Water to make the solution up to 50 c.c. t Ten per cent, solution of pyrogallic acid 2 c.c. Ten per cent, solution of carbonate of potash ... 3 c.c. Water to make the solution up to 50 c.c. 96 SECOND LESSON IN DEVELOPMENT. addition is best made by pouring the additional potash, solution into the developing cup, pouring the developer from the dish back into the cup, when thorough mixture takes place, and again over the plate. If it appeared to be over-exposed, development is proceeded with, or even, in an extreme case, some bromide of ammonium — say ten minims of the ten per cent, solution to each ounce of developer — is added. If the image be very long in appearing, showing that there has been under-exposure, alkali may be added to any amount short of that which will produce fog. Good plates should stand 200 minims to the ounce of ten per cent, of carbonate of potash without fogging. A few words should be sr.:d on the development of plates that have received instantaneous exposures, and on which portraits have been impressed. In the case of most subjects that are suitable for instanta- neous work, the brightness of the object is very great, but the contrast of light and shade is often comparatively small, as even the shadows reflect a good deal of light. For this reason there is sometimes great difficulty, not only in getting detail in the shadows, but also in getting density. The thing necessary to get both is great patience in Continuing development for a very long time with a very slow developer ; that is to say, one in which the quantity of alkali is rather below than above the normal quantity, and that of the pyro somewhat high. The dish must be rocked at least every ten seconds or so during the development, which may often with advantage be continued for a quarter or even half an-hour. "When development is protracted for a very long time, the dish should be covered to protect it from light, except when it is necessary to look at the plate. Concerning portraits, I may say that for the development of those taken out-of-doors, no particular precaution is necessary. SECOND LESSON IN DEVELOPMENT. 97 In those taken in an ordinary room there is always a tendency to hardness or chalkiness, and for this reason it is generally well to keep the pyro somewhat below the normal. It used to be commonly said that there is difficulty with gelatine plates in getting a dense enough image. Where good plates are used, such a difficulty results only from ignorance of the principles of development. The secret of getting " plucky " negatives lies in plenty of patience, beginning only slowly with but a small quantity of alkali, and if we are at all doubtful about getting sufficient density, in giving, perhaps, a slightly longer exposure than might otherwise^be thought necessary. The real difficulty lies in judging when the density is great enough. On the two following pages is printed the t^V.e referred to on page 93, showing the actual proportions of the ingredients recommended as developers by different plate makers ; the quantities being given in grains and minims per ounce of developer. E 98 SECOND LESSON IN DEVELOPMENT. a^iqdinsiq-e^ui j . raTUss , B!jo ( i I * " * : '• : : : '• : J . % P. 2 5 D O H I H £ *- ~ ( 5 B « OOmWP SECOND LESSON IN DEVELOPMENT. 99 a;iqdin8iq-^ani i g . .§ raniss^o^ 1 : : : : : :^ : :^ : : : : ' > ::::::::::::: : : : uinrpog Grains. 6" 21 21 60 to 40-40 40 7-29 5 : 04 4-32 6-75 50 •areuoqiuo KaJL ILL U. \J \Xk Ui y Grains. •areuoqxBO Grains. 12 to 30 9-37 •a^uoqrBO uinrpog Grains. 14 7 to 10 7-50 to 11-25 18 'Bnzotatay Minims. 1-87 as 1 is to 4 3 1- 80 3 V 75 3 75 3* 3 2 -50' to 4 0-60 to 4 2 to 4 1 0*83 or more 2- 30 11-33 2-50 3 3 2-25 2*40 i V 30 2-50 2-50 2-50 •aptuioig; UiniSSB'lOJ Grains. 0-23 Ammonia 0-75 0-46 0-12 012 0-50 0-50 i V 50 0 20 to 0-50 0-33 0-33 •apitnoig; xnmuouiray Grains. Bromide to 1-50 0- 90 0*75 1- 50 0*75 0-25 to 0-50 0-20 to 0 40 1- 50 0-25 0-20 or more 2- 90 0- 45 2-50 1- 26 1-25 1-08 0-11 S g dot* OO O O . V, W5 o ° ° ^ ° S H ^ >*'H^ B aaft p ^ « K h^f« « ^ *?~r*? ™ jj »-h uj „ aj ai iiuiiiifitlti fa | 013 DPS 3 3 a 9 ^ -3 o o a > ^ ^ * ► &a > £a a > ► a &ar s- 4 ^ a a a ° w W « o ^ S 3 h g .a h J? 02 CO 2 OT CO CO 00 00 • k vb6 k* C0kf5 M 0O60C0C0 «i c6 © iH c s CO co co to 00 Hi o M w ■SIM'S ■ 03 2 g eg to M it f INDEX. Abney, Cure for Colour Fog, 116 Abney on Emulsions, 5 Abney on Hydroquinone, 102 Acetate of Soda, 142 Acid, Citric, 15, 17, 19, 92, 100, 101, 102, 109, 161, 163, 184 Acid, Hydrochloric, 120, 121 Acid, Hydrochloric, for Emulsion- Making, 194, 197 m Acid, Hydrochloric, in Pbtinotype Printing, 167, 169, 172 Acid, Nitric, 145, 159 Acid, Pyrogallic, 15, 16, 18, 19, 91, 94, 101 Air-Bubbles in Developer, 119 Albumenised Paper, Double, 144, 148 Albumenised Paper, Printing on, 136 Albumenised Paper, " Salted," 148 Albumenised Paper, Sensitising, 148 Alcohol, 18 Alcohol in Emulsions, 196, 202 Alcohol in Orthochromatising Plates, 213 Alcohol for PrecipitatiDg Emul- sions, 201 Alum, 15, 17, 19, 32, 36 Alum as a Means of Preventing Frilling, 117 Alum Bath, 119 Alum Bath for Gelatino-Citro- Chloride Prints, 157 Alum Bath for "Rapid Paper," 159 Alum, Chrome, 117 Amateur and Professional Photo- graphers, 215 American Clips, 149, 154 Ammonia, 15, 16, 100, 116 Ammonia Developer, 100 Ammonia for Intensification, 124 Ammonia Fuming of Sensitised Paper, 150 Ammonia in Orthochromatising Plates, 212, 213 Ammonia Method of Emulsion MakiDg, 199 Ammonia-Nitrate Emulsions, 199 Ammonia- Nitrate of Silver, 200 Ammonia-Nitrate of Silver for Prints on Plain Paper, 154 Ammonium Bromide, 91, 96, 101 y 105, 111, 115 Ammonium Chloride, 153 Ammonium Sulpho- Cyanide, 156 Angle of Lens, Width of, 40 Aperture of a Lens, 39 Apparatus, Selection and Purchase of, 6, 7 Archer, 1, 129 Architectural Subjects, Exposures for, 84 Argentometer, 150 Arundel and Marshall, 209 Back Focus of Lenses, 37 Backgrounds for Portraits, 73 " Backing" Plates, 121 Balance, Chemical, 8, 14 "Bath" Plates, 184 Beeswax, 157 Benzine, 157 Berkley, Herbert, 91 Bichloride of Mercury, 15, 17, 124 Blanchard's, Valentine, Platinum Process, 172 Blistering of Plates, 117 Blue Litmus Paper, 16, 18, 109, 198 Blurring, 121 Bolton, W. B. ; 117 ccxxii INDEX. Bothamley, Prof. C. H., 213 Boxes, Grooved, for Packing Plates, 209 Bromide as a Retarder in Develop- ment, 92 Bromide of Ammonium, 91, 96, 101, 105, 111, 115 Bromide of Iron, 116 Bromide of Potassium, 91, 96, 102, ill, 115 Bromide of Potassium for Emulsion- Making, 194, 196, 199 Bromide of Silver, 158 Bromide of Sodium, 105 Bromide Paper for Enlargements, 186, 189 Bromide Paper, Printing, 152, 160 Bronzing of Prints, 139, 165 Brown Colour in Toning, 144, 151 Bunsen Burner, 194 Burnishing Prints, 178 Burnishing Prints on "Rapid" Paper, 160 Calcium Chloride, 167 " Calcium Tubes," 167 Camera, The, 9, 10, 54 Camera Case, 12 Camera in the Field, 50 Camera Screw, 54 Canvas for Washing Emulsion, 193 Carbonate of Potash, 15, 16, 19, 91, 94, 104, 161, 182 Carbonate of Soda, 91, 101, 104, 107, 150, 160, 163, 164, 182 Carbonate of Silver, 151 Carbon Process, 130 Carbutt, 133 Carriers for Dark Slide, 9 Case for Camera, 12 Castile Soap, 180 Caustic Potash, 102 Caustic Soda, 103 Celluloid Films, 133 Chemical Fog, 114 Chemicals, 15 Chemical Balance, 8, 1 4 Chloride of Ammonium, 153 Chloride of Calcium, 167 Chloride of Gold, 142, 156, 164 Chloride of Iron, 116 Chloride of Lime, 159 Chloride of Silver, 158 Chloride Plates for Reduced Nega- tives, 191 Chloride Plates for Transparencies, 183 Chloro-Platinite of Potassium, 173 Chrome Alum, 117 Citrate of Iron for Developing Transparencies, 184 Citric Acid, 15, 17, 19, 92, 100, 101, 102, 109, 161, 163, 184 Citro-Chloride Paper Printing, 152, 155 Citro- Oxalate of Iron for Develop- ing "Rapid" Paper, 159 Clark, Lyonel, 174 Clark's, Lyonel, Platinum Process, 172 Cleaning Glass, 203 Clearing Bath, 120 Cloud Negatives, 175, 177 Cloud Negatives (Paper or Film), 130 Coating Dry Plates, 203, 204 Cold Bath Platinotype Process, 168 Collodio-Chloride Paper Printing, 152, 157 Collodio-Bromide Plates, 184, 191 Collodion Process, 1 Colour Fog, 116, 120 Composition of Pictures, 51 Concluding Remarks, 215 Corrosive Sublimate, 17 "Cutting Moulds" for Trimming Prints, 141 Cyanine, 213 Dark Room, The, 20 Dark Room Lamps, 8, 14, 22 Dark Slide, 9 Davison, George, 171 Debenham, W. E., 21 Defects and Remedies, 114 Defects in Silver Prints, 162 Density of Image, Too Great, 119 Density, Reduction of, 139 INDEX. ccxxiii Density, Want of, 118 Deposit, White, on Plates, 120 Depth of Focus, 39 Developer, Irregular Action of, 121 Developers, Tables of Ingredients in, 98, 99 Developing Bromide Prints, 160 Developing Lantern Slides, 184 Developing Orthochromatic Plates, 210 Developing Platinotype Prints, 167 Development, First Lesson in, 32 Development of Films, 134 Development of "Rapid" Paper, 159 Development of Transparencies, 182 Development, Second Lesson in, 90 Diameters of Lens Stops, 79, 86, 88 Diaphragms of Lenses, Diameters of, 79, 86, 88 "Dipper," 111 Dishes for Development, &c, 8, 13 Distilled Water, 194, 196 Distortion by Lenses, 41 " D " Lens, 72 Double Albumenised Paper, 144, 143 Double Dark Slides, 9 Doublets, Wide- Angle and Instan- taneous, 47 Drawing Paper, Silver Prints on, 152 Drop Shutter, 65 Drying Box, 193, 207 Drying Cupboard, 193, 207 Drying Gelatino - Citro - Chloride Prints, 156 Drying Gelatino -Bromide Plates, 203 Drying Prints on " Rapid " Paper, 159 Double Transfer Carbon Process, 130 Eastman Photographic Materials Co., 131, 134 Eastman Films, 131, 134 Eder, 5, 213 Eder on Modern Dry Plates, 5 Eikonogen, 104, 105, 109 Eikonogen, Solubility of, 105 Emerson, P. H., 53 Emulsion, Gelatine, Manufacture of, 192 " Emulsions, Photography with/' Abney, 5 Enlarged Negatives, 190 Enlarging, 182, 185 Eosine, 212 Equivalent Focus of Lenses, 37 Erythrosine, 212, 213, 214 Exhibitions, 217 Exposure of the Plate, 37 Exposures for Portraiture, 85, 87 Exposure Tables, 78, 82, 84, 87 Ferric Chloride, 161 Ferric Bromide, 116 Ferric Oxalate, 116 Ferro- Citro- Oxalate for Developing " Rapid Paper," 159 Ferrous Oxalate Developer for Bro- mide Prints, 161 Ferrous Citrate for Developing Transparencies, 183 Ferrous Oxalate, 32 Ferrous Oxalate Developer, 109 ? 116, 117, 121 Ferrous Oxalate for Developing "Rapid " Paper, 159 Ferrous Oxalate for Developing Transparencies, 182, 183 Ferrous Sulphate, 110, 112 Field, Flatness of, 41 Film Negatives, 129 Film, Unequal Thickness of, 120 Films, Celluloid, 133 Films, Eastman, 131 Filtering Funnel, 194 Fixing Bromide Prints, 161 Fixing Gelatino - Citro - Chloride Prints, 157 Fixing Plain Paper Prints, 154 Fixing Prints, 146 Fixing " Rapid " Prints, 159 Fixing Solution for Negatives, 19, 32, 26 CCXXLV INDEX. Fixing Solution for Prints, 142 Fixing Transparencies, 182 Flatness of Field of Lenses, 41 Flatness of Image, 118 Flattening Prints on Albumenised Paper, 178 Flexible Films for Negatives, 129 Floating Albumenised Paper, 149 Focal Length of Lenses, 37 Focus, Depth of, 40 Focus of Lenses, 37 Focussing Cloth, 8, 13, 54 Focussing Magnifier, 54 Fog, Chemical, 114 Fog Colour, 117, 120 Fog from Light, 114 Fog, General, 114 Fog, Green, 116, 120 Fog in Orthochromatic Plates, 212 Fog, Red, 116, 120 Fog, Yellow, 120 Frame, Printing, 137 French Chalk, 157 Frilling, U7 Full Aperture of a Lens, 39 Fuming Sensitised Paper, 150 Funnel for Filtering, 194 Gelatine Emulsion, 192 Gelatine for Emulsion- Making, 194, 196, 199 Gelatine for Printing on Plain Paper, 153 Gelatino - Bromide Emulsion for Positive Printing, 160 Gelatino-Bromide Paper for Enlarge- ments, 186, 189 Gelatino-Bromide Paper, Printing, 152, 160 Gelatino-Bromide Plates for Lantern Slides, 184 Gelatino-Bromide Plates for Re- duced Negatives, 191 Gelatino-Bromide Plates for Trans- parencies, 182 Gelatino -Chloride Paper Printing, 152, 156 Gelatino -Chloride Plates for Lan- tern Slides, 184, 191 Gelatino -Chloride Plates for Re- duced Negatives, 191 Gelatino- Chloride Plates for Trans- parencies, 182 Gelatino Citro- Chloride Paper Printing, 152, 155 General Fog, 114 Gold Chloride, 142, 156, 164 Graduated Measures, 8 Green Fog, 116, 120, 199 Group Lens, 72 Groups, 77 Grooved Light-tight Boxes for Packing Plates, 209 Hair-Sieve for Washing Emulsion, 193, 195 Halation, 121, 130 Hartshorn, 16 Head Rest, 72, 76 Heinrich's Gelatine, 194, 197 Henderson's, A. L., Washing Vessel for Emulsions, 196 Hock Bottles for Emulsion Making, 194 Hot Bath Platinotype Process, 167 Hydrochloric Acid, 120, 121 Hydrochloric Acid for Cleaning Plates, 203 Hydrochloric Acid for Emulsion Making, 194, 197 Hydrochloric Acid in Platinotype Printing, 167, 169, 172 Hydroquinone, 102 Hydroquinone Developer for Bro- mide Prints, 161 Hydroquinone for Developing " Rapid" Paper, 159 Hydroquinone for Developing Transparencies, 182 Hydroxylamine for Developing "Rapid "Paper, 159 Hyposulphite of Soda, 15, 17, 19, 142, 156, 161 Hyposulphite of Soda as an Accele- rator in the Iron Developer, 112 Image, Flatness of, 118 Image, Reversal of, 122 INDEX. CCXXV Instantaneous Doublet, 47 Instantaneous Exposures, Develop- ment of, 96 Instantaneous Shutters, 63 Instantaneous Photography, 61 Intensification, 139 Intensification of Negatives, 123 Interiors, Exposures for, 84, 87 Introduction, 1 Iodide of Potassium in Emulsion Making, 194, 197, 199 Iron, Oxalate of, Developer, 109, 116, 117, 121 Irregular Action of Developer, 121 Isochromatic Plates, 210 Ives, 213 Japanese Paper, Printing on, 152 Jennings, Payne, 144, 151 Lamp for Dark Room, 8, 14, 22 Landscape Lens, Wide- Angle, 13 Lantern Plates, Sizes of, 184 Lantern Slides, Vertical Lines in, 185 Lantern Slides, 182, 184 Latitude of Exposure, 90 Lens, The, 8, 12, 54 Lenses, 37 Lenses, Diameters of Stops, 79, 86, 88 Lenses for Enlargement, 189 Lenses for Portraiture, 73 Lenses, Uniform Standard for, 79 Light Fog, 114 Lighting of Subject in Portraiture, 74 Linen, Printing on, 152 Lime Chloride, 159 Litmus Paper, 198 Litmus Papers, Blue and Red, 16, 18 Macbeth, Norman, 51 Magic Lantern, 184, 186 Magnesium Wire for Exposing Transparency Plates, 183 Magnifier for Focussing, 54 Manufacture of Gelatine Emulsion, 192 Marble -like Markings on Prints, 163 Marion and Co., 158 Masking-out Skies, 177 " Matt" Surface Prints, 137 Matt Surface Silver Printing, 152 Mealiness of Prints, 163 Measuring Glasses, 8 Mercury, Bichloride of, 15, 17 Mercury Intensification, 124 Meta- bisulphite of Soda, 91 Metallic Spots on Prints, 165 Methylated Spirit, 15, 17, 201 Morgan and Kidd's Paper, 158 "Moulds" for Trimming Prints, 141 Mounting Prints, 178 Naturalistic Photography, 53 Naturalists, 53 Negative, Definition of, 27 Negative Varnish. 15, 18, 126 Negative Varnish for Prints oit Plain Paper, 153 Nelson's Gelatine, 194, 196 Nitrate of Silver, 148, 154 Nitrate of Silver for Emulsion Mak- ing, 194, 196, 199 Nitric Acid, 154, 173 Note-Book for Photographers, 85 Opaque Spots on Negatives, 119 " Open Landscapes," Exposures for, 84, 87 Optical Lantern, 184 Orange Light for Dark Room, 21 Orthochromatic Plates, 210 Orthographic Lens, 47 Orthoscopic Lens, 38, 47 Over-Exposure, 94, 115 Oxalate of Iron, 116 Oxalate of Iron Developer, 109, 116, 117, 121 Oxalate of Iron Developer for Bro- mide Prints, 160 Oxalate of Iron for Developing Transparencies, 182, 183 Oxalate of Iron for Developing " Rapid " Paper, 159 I Oxalate of Potash, 110, 112 I ccxxvi INDEX. Oxalate of Potash in Platinotype Printing, 167 Packing Gelatino-Bromide Plates, 203, 209 Paper Negatives, 129 Photographers, Amateur and Pro- fessional, 215 Photographic Societies, 216 Photographic Society's Uniform Standard for Lenses, 79 Photo-Mechanical Processes, 130 Pizzighelli's Printing- Out Platino- type Process, 171 Plain Paper, Silver Printing, 152 Platinotype Co., 166, 168, 169 Platinotype, 160, 166 Platinotypes, Sepia, 170 Pneumatic Holder, 204 Polishing Plates, 203 Portrait Lens, 45 Portraits, Development of, 96 Portraiture, 71, 83 Portraiture in Ordinary Room, 74, 84 Portraiture Out of Doors, 73 Posing of Subject in Portraiture, 74 Potash, Carbonate of, 15, 16, 19, 91, 94, 104, 161, L82 Potash, Caustic, 102 Potassium Bromide, 15, 17, 91, 94, 105, 115 Potassium Bromide for Emulsion Making, 194, 196, 199 Potassium Carbonate, 161, 182 Potassium Chloro-Platinite, 173 Potassium Iodide in Emulsion Making, 194, 197, 199 Potassium Oxalate, 110, 112 Potassium Oxalate in Platinotype Printing, 167 Precipitation of Emulsions with Alcohol, 201 Pringle, Andrew, 211 Printing Frame, 137 Printing with Ready -Sensitised Paper, 136 Printing-Out Platinotype Process, 171 Prints, Trimming, 140 "Processes of Pure Photography," Professional and Amateur Photo- graphers, 215 Protosulphate of Iron, 110, 112 Purchase of Apparatus, 7 Purple Colour in Toning, 144, 151 Pvro for Developing Transparencies, "165 Pyrogallic Acid, 15, 16, 18, 19, 91, 94, 101 Pyrogallic Acid Stock Solution, 18 Pyrogallic Developer for Bromide Prints, 160 Pyrogallol, 91 Racks for Dry Plates, 209 Rapid Emulsion, Manufacture of, 196 Rapidity of Lenses, 41 " Rapid" Paper for Enlargements, 189 "Rapid " Printing Paper, 152, 158 Rapid Rectilinear Lens, 12, 44, 73 Rapid Rectilinear Lens for Enlarge- ment, 189 Rapid Rectilinear or Symmetrical Lens for Enlargement, 189 Rapid Symmetrical Lens, 12, 44, 73 Rapid Symmetrical Lens for En- largements, 189 Ready -Sensitised Paper, 136 Ready- Sensitised Plain Papers, 148 Rectilinear Lens, Wide-Angle, 44 Rectilinear Rapid Lens, 12, 44, 73 Red Fog, 116, 120 Red Litmus Paper, 16, 18, 198 Reducing Photographs, 182, 191 Reduction of Density, 139 Reflector in Portraiture, 74 Refusal of Prints to Tone, 163 " Rembrandt " Effects, 76 Remedies for Defects, 114 Remedies for Defects in Silver Prints, 162 Retardation of Development by Bromide, 92 Retouching, 130 INDEX. ccxxvii Reversal of Image, 122 Rising Front, 50, 55 Robinson, H. P., 53 Roll Holder, 131 Roller Slide, 129, 131 Rolling Prints, 179 Rolling Prints on "Rapid" Paper, 160 Rose Bengal, 212 "Salted" Albumenised Paper, 148 Saturated Solutions, 110 Scott, Dr. J. A.'s Table of Intensity of Light, 83, 89 Scovill and Adams Co., 211 Scratches on Plates, 120 Screw for Camera, 54 Scrim for Washing Emulsion, 193 Selection of Apparatus, 6 Sensitised Paper, 127 Sensitised Paper (Ready), 136 Sensitised (Ready) Plain Papers, 152 Sensitising Plain Paper, 154 Sensitising Albumenised Paper, 148 Sepia Tones in Platinotype Printing, 170 Sepia Platinotypes, 170 Shumann, 213 " Shut- over " Jars for Emulsion- Making, 193 Shutters, Instantaneous, 63 Sieve for Washing Emulsion, 193 Silver, Ammonia-Nitrate, for Prints on Plain Paper, 154 Silver Bath for Paper, To Keep in Good Condition, 150 Silver Bath for Sensitising Paper, 148 Silver Carbonate, 163 Silver, Chloride and Bromide of, 158 Silver Iodide in Orthochromatic Plates, 212 Silver Nitrate, 148, 154 Silver Nitrate for Emulsion- Making, 194, 196, 199 Silver Printing on Plain Paper, 152 Silver Printing Processes, Various, 152 Silk, Printing on. 152 Single Lens, 42, 73 Single Transfer Carbon Process* 130 Size of Plate, 6 Sizes of Lantern Plates, 184 Skies in Negatives, 174, 175 Sky in Photographs, 62 Slab for Coating Dry Plates, 193, 205 Slide, Roller, 129 Slides, Lantern, 182, 184 Soap, Castile, 180 Societies, Photographic, 216 Soda, Acetate of, 142 Soda, Carbonate of, 91, 101, 104, 107, 150, 160, 163, 164, 182 Soda, Caustic, 103 Soda Developer, 101 Soda Hyposulphite, 15, 17, 19, 112, 142, 156, 161 Soda, Meta- Bisulphite of, 91 Soda Sulphite, 15, 17, 19, 91, 92, 102, 120, 160 Soda Sulphite for Intensification, 125 Soda, Washing, 145, 151 Sodium Bromide, 105 Sodium Sulphite, 160 Solarisation, 122 Solubilities of Photographic Chemi- cals, 220 Solutions, Saturated, 110 Spiller, Arnold, 150 Spirit, Methylated, 15, 17, 201 Spots on Negatives, 119 Spots on Prints, 165 Squeegee, 157 Squeegee for Mounting Prints, 178 Stained Negatives, 119 Stiff and Sons, 193 Stock Solutions, 18, 30, 93 Stops of Lenses, Diameters of, 79, 86, 88 Streaks on Plates, 120 Sublimate, Corrosive, 17 Sulphate of Iron, 110, 112 12 ccxxviii INDEX. Sulphite of Soda, 15, 17, 19, 91, 92, 102, 120, 160 Sulphite of Soda for Intensification, 125 Sulpho- Cyanide of Ammonium, 156 Sunning of Silver Bath, 150, 163 Swan, J. W\, 91, 102 Swing-Back, 12, 50, 57 Symmetrical Lens, Wide -Angle, 44 Symmetrical Lens, Rapid, 12, 44, 73 Table of Solubilities of Photo- graphic Chemicals, 220 Tables of Exposure, 78, 82, 84, 87 Tables of Ingredients in Developers, 98, 99 Talbot, Fox, 129 Talbotype Process, 129 Tea-pot for Coating Plates, 204 Test Papers, 16, 18 Tone, Prints Refuse to, 163 Tone, Unevenness of, 164 Toning Gelatino - Citro - Chloride Prints, 156 Toning Plain Paper Prints, 155 Toning Prints, 143, 151 Toning "Rapid" Paper, 159 Toning Ready- Sensitised Paper, 136, 141 Toning Solution, 142, 163 Transparencies, 182, 190, 195 Transparent Spots on Negatives, 119 Trimming Prints, 140 Triplet Lens, 39 Tripod Stand, The, 8, 13, 54 Tripod for Coating Plates, 205 Under- Exposure, 92 Unequal Thickness of Film, 120 Unevenness of Tone, 161 Uniform Standard for Lenses, 79 Varnishing, 123, 126 Varnish, Negative, 15, 18, 126 Varnish, Negative, for Prints on Plain Paper, 153 Vertical Baths, 111 Vertical Lines in Lantern Slides, 185 Vignetting Prints, 174 Vogel, 213 Warnerke, L., 129, 158, 159 Warnerke's Sensitometer, 202 Washing Emulsions, 196 Washing Prints, 146 Washing Soda, 145, 151 Washing Soda for Preserving Sensi- tised Paper, 151 Wellington, J. B., 213 Wet Plate, 190, 191 Wet Process, 190 Whatman's Drawing Paper, Prints on, 152 White Deposit on Plates, 120 Whitening for Polishing Plates, 203 White Spots on Prints, 165 Wide- Angle Doublet, 47 Wide -Angle Landscape Lens, 13 Wide- Angle Rectilinear Lens, 44 Wide- Angle Symmetrical Lens, 44 Width of Angle of Lens, 40 Williams, G. F., 208 Willis, W., 166, 168, 171 Yellow Fog, 120 Yellow Light for Dark Room, 21 Yellowness of Prints, 163 Yellow Stain in Negatives, 119 Carter & Co., Printers, 5, Furnival Strett, Holborn, E.C. The FRENA, THE HAND-CAMERA OF THE DAY, CARRIES 40 It has a Beck Autograph Rapid Rectilinear Lens, It has a Shutter giving Exposures from \ to -§V second; also Time Exposures. It has a Swing -hack and Level. The manipulation is so simple that it can be used by the absolute Novice. A Hand-book with full instructions is supplied with each Camera. The Camera is re-charged with greater rapidity and ease than any other Hand- Camera. ''LIKE A PACK OF CARDS." A Single Exposure can be removed at any time for Development. Useful alike for the Experienced Photographer or the Entire Beginner. Frena Films by all leading Makers are supplied. Full Paeticulabs on Application to — R. & J. BECK, Ltd., 68, Cornhill, London, E.C. OR ANY PHOTOGRAPHIC DEALER. i y 5 g SS 8 p 1 _§ ^ £ o 00 i — i ^ p,p * o 1-5 s CO J~p „ .83 8 o P ^ ao o 3 o GO 5 3 p o • p fe o 03 £~p ° SO S a? P TO CO CO "6 * ft-P ft"* P CO 03 43 u a _ d) O'H ^ ft o3 CD i— • PI > © 03 -§§ & « P b0 >> 2 p +» o 03 g ^3 * I * * > 2 do® * S o i«r| s © 2 © fl s ' &0© ro p s .2 P(S ro C3 ^ 43 O " , , H 03 2 rH r O < «! MS d 03 F 03 ^ ee a P 5 - o^.h o - O l ft , . «3 03 o3 p o o 4^> o O CD CD o •iH S5 O Q S5 o to o 3 CD CO "C m CO CO S5 o u. FIELD AND STUCIO CAMERAS AND STANDS OF ALL SIZES. PERKEN, SON, & RAYMENT,m?S% LONDON. Establish ed 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus. - 'OPTIMUS' ~ RAYMENT'S "BEfiT CAMERA. EXTRA LONG FOCUS. British Journal of Photography says: " The present model Ray ment Camera is among the very lightest of actually rigid cameras offered to the public. " The rapidity of opening and closing is greatly facilitated by the additional arrangement for throwing the pinion out of gear from the rack. " There is no curtailment of view when lenses of short focus and wide angular aperture are in use. "All movements necessary to the modern scientific photographer are included in this com- pact instrument." Price includes 3 Double Dark Slides— HXH 5x4 6ix4f 8£x6| 10x8 12x10 15x12 inches. 120/- 126/- 145/- 168/- 212/- 258/- 314/- 'OPTIMUS' ™h,c OUTFIT, Including Rayment Camera, Three Double Dark Slides, 11 Optimus" Rapid Rectilinear Lens Instantaneous Shutter, Tripod, "Waterproof Case, complete — Hx 5x4 6ix4f 8|x6^ 10x8 12x10 15x12 inches. £10 £11 £12 £15 £20 £2$ £30 This Outfit, with Extra Rapid Eury«cope Lens, instead of Rapid Rectilinear, extra— 27'- 27 ■/- 37/- 36/- 78/- 200/- PEBKEN, SON, & RAYMEMT.a^SS LOKDON. Established 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus, - ' OPTIMUS' -* "OPTIMUS" STEREOSCOPIC LENSES. Sold in Pairs, accurately matched. Giving brilliant definition, and covering 3£ by 3| perfectly. Rapid Rectilinear Aperture F/8 ... ... , per pair 80/- „ Euryscope „ E/6 „ 120/- The above are recommended for either Stereoscopic Slides or Photographic Transparencies lor Magic Lantern Projection ; being of short focus and fairly wide angle, tbey include a very comprehensive amount of field. The Optical quality is such that the resulting pictures will ibear almost unlimited enlargement. OPINIONS OF "OPTIMUS" LENSES. « OPTIMUS RAPID EURYSCOPE," manufactured by the firm of Perken, Son, and Payment, Hatton Garden. With its full aperture of lfin. (its equivalent focus being llin ) it defines with extreme brilliancy, and when used with a stop it easily covers a 10 by 8 plate to the corners, which is larger than that engraved on the mount as its possibility. "Working as it does with such a large aperture (//6 approx.) it serves as a portrait and group lens, as well as a landscape and copying objective. There is no doubt of its proving a most useful lens. — J. Traill Taylor —British Journal of Photography. * OPTIMUS EURYSCOPE." — I am much pleased with the 9 by 7 received last week. It covers 12 by 10, and gives splendid definition. For a good, useful, all-round lens I consider it perfect.— E. Brightman, Hon. See. Bristol and West of England A.P.A. " OPTIMUS EURYSCOPE."— When in your establishment you kindly lent me one of your 7 by 5. I like the lens so well, I do not want to part with it.— Chapman Jones, F.I.C., F.C.S. '* OPTIMUS EURYSCOPE."— This lens is of extra large diameter, the aperture being //6, and, while admitting of the most rapid exposures, gives fine marginal definition. We have obtained with it excellent portraits in an ordinary sitting-room. The lens is a most useful one all round.— T. C. Hepworth. — The Camera As I have often said before, I consider these lenses unequalled.— E. J. Wall. — Amateur Photographer. I have tried the 7 by 5 " OPTIMUS " Euryscope. It is a very satisfactory lens, and covers the whole plate for interiors with //16 ; being able to work at //6 makes it very handy for por- traits.— J. G. P. Vkreker. Frith's series of "Life in London Streets'* were all taken with 12 by 10 Portable u OPTIMUS " lens. Had an " Optimus " rapid symmetrical been used, the plates would have been over-exoosed with full aperture.— G. Lindsay Johnson, M.A., M.B., F.R.C.S., England. — Amateur Photographer. " OPTIMUS " LENS. — I have taken trains going at 30 miles an hour, and think the lenses perfect for rapidity and definition.— E. J. Wall.— Amateur Photographer. . . . We may call attention to the extensive optical and metal works that Perken, Son, and Rayment have established in Hatton Garden, and their photographic cabinet factory. At the former we were much interested in the glass grinding departments— one for photographic lenses, another for spectacles ; and we were surprised tn find in London such extensive work- shops for the metal parts of cameras and optical lanterns.— Photographic News. We are pleased to find upon trial that the Lens (" Optimus" Rapid Rectilinear) sent for leview is really an excellent instrument.— Photographic News. If E. G. E. wants the finest lens in the market, he cannot do better than get the "OPTIMUS." — Professor De Frere —Amateur Photographer. Trade 'OPTIMUS Mark. IRIS DIAPHRAGMS FITTED TO RAPID EURYSCOPE AND RAPID RECTILINEAR. 7X5 ii/- 9x7 12/6 10X8 14/- 12X10 16/- 15x12 18/- 18x16 20/- extra. 'OPTIMUS' RAPID EURYSCOPE LENS. The aperture is F/6. The Lenses are of Special Optical Glass, con- structed with the nicest precision of curvatures, so maintaining good marginal definition, coupled with the most extreme rapidity. 5x4 6X5 7X5 8X5 9x7 10x8 12x10 15x12 63/- 78/- 94/6 no/- 126/- 220/- 380/- 580/- 'OPTIMUS' WIDE-ANGLE EURYSCOPE LENS. F/9-50. This aperture is exceedingly open for wide-angle work. The definition, however, is in no way sacrificed, as the curvatures are most perfectly accurate, and the minute detail in architectural and interior subjects is rendered with the maximum of crispness and a total absence of distortion. To cover 5x4 Equiv. Focus, inches Z\ Price 63/- 7X5 94/6 9X7 6 126/- 10X8 220/- 12X10 12 380/- 'OPTIMUS' RAPID RECTILINEAR LENS. Aperture F/8. Second only to the above for Rapidity, therefore well suited for instantaneous effects, outdoor groups and views, as well as interiors. Copying and enlarging are also within the capabili- ties of this lens— in fact, its work may be styled Universal. 5X4 6 ><5 7x5 8X5 9x7 10x8 12x10 15x12 18x16 36/- 50/- 56/- 70/- 90/- 142/- 180/- 225/- 275/- 'OPTIMUS' WIDE-ANGLE SYMMETRICAL LENS. Aperture F/16. Specially adapted for Architecture. Can be used to advantage when very close to the s abject. 5x4 7X5 9x7 10x8 12x10 15x12 18x16 42/- 58/- 90/- 142/- 180/- 225/- 275/- 'OPTIMUS' QUICK-ACTING PORTRAIT LENS. Aperture F/4. Specially constructed for short exposures in Portrait- ure. Tbey are second to none, definition being maintained by their perfect optical qualities. 4£in. Focus, Carte-de-Visite, 1 B, diameter 2in. ... 90/- 5f in. „ Cabinet 2 B, „ 2f in. ... 120/- 9in. „ Grand Cabinet, 3 B, „ 3^in. ... 180/- 'OPTIMUS' STEREOSCOPIC LENSES. Sold in pairs, accurately matched. Giving brilliant definition, and covering 3J by 3| perfectly. Rapid Rectilinear Aperture F/8 per pair 80/- „ Eury scope F/6 120/- The above are recommended for either Stereoscopic Slides or Photographic Transparencies for Magic Lantern Projection ; being of short focus and fairly wide angle, they include a very comprehensive amount of field. The optical arrangement is such that the resulting pictures will bear almost unlimited enlargement. PERKEM, SON, & RAYMENT, VSSXX LONDON. PERKEN, SON, & RAYMENT, LONDON. Established 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus. - 'OPTIMUS' " OPTIMUS " CAMERA de LUXE FOR THE HAND OR STAND. Possesses Extra Long Focussing Adjustment. This Camera lias the advantage of being very light indeed, and very small indeed. In- cluding the Double Dark Slides, its weight is but 2|lbs , whilst its dimensions, including Black Morocco Leather Covering, are only 6£ by 5^ by 5J. The Telescopic Base-board sufficiently ex- pands the bellows to allow the use of a lens of 11£ inches focus. The focussing is by Rack-and- Pinion arrangement. A Finder is also provided for instantaneous snap-shots. A Swing-Back arrangement and a Roller Blind Shutter, giving Exposures of varying speeds, are affixed. The Lens (Extra Rapid Euryscope) is attached inside the front, so that the closing up and opening out of the Camera is an operation of only one second. For either out or indoor use it is a com- prehensive and self-contained little machine. Price, including Three Dark Slides, Roller-Blind Shutter, and "Optimus" Extra Rapid Euryscope, mounted in Aluminium, with Iris Diaphragm, For Dimensions of Camera Ex. Dark Plates when closed. Price. Slides. 4|by3| 61 by 51 by 5| £10 10 0 ... 14 6 4 7 f , 5& „ 6 12 12 0 ... 14 0 6i „ 4| 9 tf $ » 8 15 15 0 ... 15 0 "Beginners' Guide to Photography " Cloth Covers % 6d. PERKEN, SON, & RAYMENT, SWS^S, LONDON. Established 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus, ~ 'OPTIMUS' ~ "OPTIMUS" IMPROVED MAGAZINE CAMERA. (24 Films on Celluloid, or, if preferred, 12 Films on Glass.) The original " Optimus " Magazine Camera was highly extolled on all sides as the least com- plicated of Reservoir Cameras ; but the present Model is superlatively perfect in the simplicity of its parts, and absence of unnecessarily intricate mechanism. The grooves in which the Plates are placed are continuous from the upper or Reserve Chamber to the lower or Exposure Chamber. The Plates simply slide by their own weight from the upper to the lower chamber, without passing from box to box through a slot or performing any acrobatic feats. The Rapid Euryscope Lens can be accurately focussed from outside the box by Rack and Pinion. The Finders give proportionate images. A well-finished Roller Blind Shutter is fitted. This Instrument will be appreciated by those who desire Simplicity and Efficiency. Price, with " Optimus " Extra Rapid Euryscope Lens, mounted in Aluminium, with Iris Diaphragms £10 10 0 " OPTIMUS " CYCLIST'S CAMERA. This little Instrument is capable of producing results of first merit. It includes Shutter and Dark Slide as well as Rapid View Lens. PRICE 25/- PERKEN, SON, & RAYMENT, LONDON. Established 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus. 'OPTIMUS' Trade Mark. OPTIMUS" CAMERA. LONG FOCUS. The Instrument can be set up almost instantaneoously, has no loose parts, and includes all motions, having hinged focussing screen (adjusted by rack and pinion action), double swing- back, cross fronts reversing back arrangement so that oblong dark slides give either horizontal or vertical pictures without unscrewing the Camera from the tripod. Price of Camera, including 3 Double Dark Slides — 4iby3i 130/- | 5 by 4 1 6£by4f 1 8£ by 1 10 by 8 1 133/- 1 137/- 1 175/- 1 227/- 12 by 10 275/- 15 by 12 353/- OPTIMUS" PHOTOGRAPHIC OUTFIT. Comprising Camera as above, 3 Dark Slides, " Optimus 99 Rapid Rectilinear Lens, Instanta- neous Shutter, Tripod Stand, and Waterproof Case, complete — H by 3£ 6£ by 4f 8} by 6£ 10 by 8 12 by 10 15 by 12 £10 £12 £15 £20 £23 £31 This Outfit with Extra Rapid Euroscope Lens, instead of Rapid Rectilinear, extra — H\>jH 6£by4f 8£ by 6£ 10 by 8 12 by 10 27/- 37/- 36/- 78 - 200/- "OPTIMUS'' STUDIO CAMERA. Specially arranged for Studio Use. " Invited to say if, in our estimation, the Studio Cameras of Perken, Son, and Rayment could be improved in any way whatever, for the purpose for which they are intended, we must answer, No!" — British Journal of Photography, This Camera is perfectly rigid, has double length of Bellows to suit small studios where large pictures are required, is fitted with Mechanical Adjustment to Focussing arrangement and to the swing-back. It is in all respects a perfect instrument. Camera with repeating frame masks, and one single dark slide— 6£ by 6i 145/- 1 &h by 8£ 10 by 10 12 by 12 l I 188/- 225/- 265/- 1 15 by 15 325/- Tradb Discount List on Application. THE MAQIC LANTERN: Its Construction and Use • plete instructions. PRICE 6i. "OPTIMUS" MAGIC LANTERNS. Suited for DRAWING ROOM and LECTURE HALL. Limelight may be adopted without alteration at an extra cost of 16s. Each Magic Lantern is efficient for exhibitions. The Lens gives crisp definition, being a superior Achromatic Photographic Combination with rack and pinion. It is fitted to a tele- scopic lengthening tube, so gaining increased focal accommodation. The Condenser is com- posed of two plano-convex lenses of four inches diameter. The Refulgent Lamp has three wicks (or four wicks Is. extra), yielding a brillian'ly-illuvninated picture. Each is complete in box. Superior Japanned Metal, 30/- Student's Lantern (to take demon- strating tank) with finished Braes Sliding Tubes, 40/- Russian Iron Body, Brass Sliding Tubes, 45/- Perforated Russian Iron Body, I Mahogany outside Body, Two I Mahogany outside Body, Two Brass sliding Tubes, 50/- I Panelled Doors, Brass Stages | Doors, Brass Stages, and | and Sliding Tubes, 82 - j 3 draw Sliding Tubes, 105/- "QPTIMUS" LANTERN, FOR LIMELIGHT. TRIPLE. Superior Mahogany Body, 6 Panelled Doors, Brass Stages and Tubes, Achromatic Front Lenses, Compound Condensers, £17 10 O BI-UNIAL. Superior Mahogany Body, 4 Panelled Doors, and Achro- matic Photographic Front Lens, Compound Condensers, all Brass Stages and Tubes, £10 10 0 Lantern Photographs, Plain, Is ; Coloured, Is. 6d. each. "OPTIMUS" SAFETY SATTJRATOR, with JET £3 10 0 100 CANDLE-POWER OIL LAMP FOR MAQIC LANTERNS ... 1 5 O CATALOGUE POST FREE. PERKEN, SON, & RAYMENT, LONDON. PERKEN, SON, & RAYMENT, !yS5£ LONDON. Established 1852. Catalogue Post Free. Manufacture Lenses, Cameras, and Photographic Apparatus. - ' OPTIMUS' * OPTIMUS" ENLARGING and REDUCING APPARATUS. Patent Quick-Acting Rack and Pinion Adjustment. This instrument comprises superior Lantern— with, hody of Russian Iron— "with Bellows Camera adjusted by Patent Quick- Acting Rack-and-Pinion. The Lantern is fitted with a powerful (3-wick) Refulgent Lamp, giving brilliant illumination. A negative 4£in. by 3Jins may well be enlarged to 40in. by 30in., making a suitable wall picture. Price, with Compound Condenser, complete : 5-in. Compound Condenser ... 95/- Superior Projecting Lens 27/- 6 „ ... 115/- „ „ 27/- * „ ,, ... 135/- „ „ 27/- 8 „ „ ... 180/- „ „ 39- 9 h ... 250/- „ 39/- „ „ ... 285/- „ „ 63/- L2 „ „ ... 450/- „ „ 63/- U „ „ ... 500/- „ „ 120/- When large-sized Condensers are employed, it will be found advantageous to use the Oxy- hydrogen or Oxy-calcium Lime-light Burners ; but good results are obtained with the Reful- gent Mineral Oil Lamps supplied with the apparatus. "OPTIMUS" COMPOUND CONDENSERS (MOUNTED) FOR ENLARGEMENTS. Inches Diameter 3£ 4 42 5 6 7 8 9 10 12 8/- 8/6 16/6 24/- 39/- 50/9 69/6 93/6 132/- 222/- Photographic Books by Prof. W. K. Burton, C.E. Price Is., per post Is, 2d. OPTICS FOR PHOTOGRAPHERS. Giving Full Instructions, based on experience, in the Use of Photographic Lenses, together with the Theoretical considerations involved. PHOFTJSEIjY illustrated . Price Is., per post Is. Id. POCKET-BOOK FOR PHOTOGRAPHERS. Including the usual space for NOTES, &c, with TABLES FOR FACILITATING EXPOSURES A Handy Book for Reference. Price Is., per post Is. 2d. A CASKET OF PHOTOGRAPHIC GEMS. Being a Collection o Dodges, Eeceipts, Entertaining Experi- ments, &c, in connection with Photography and its branches. CLASSIFIED AND ARRANGED FOR READY REFERENCE. Send for complete Catalogue of Photographic Books to— Oj^IR/TIEIR, &c CO, (Late PIPER & CARTER), PRINTERS (So PUBLISHERS, 5, Furnival Street, Holborn, London^ E,C. ALL IN THE PHOTOGRAPHIC WORLD ! ! ! HAVE TWO THINGS TO DO ! ! ! This Page tells you one. Page inside front cover tells the other. GET the Annual. Facsimile of Cover here shown. 764 PAGES, 1,154 mnstrations, It can be copied. You want ..^^m?^ Unsolicited Remark: know no more. " i> est Magniflque/ Its contents tells you everything you want. How to Buy, How to Use, and How to^ Save Money. THE KODAK. The best known and most deservedly popular Hand and Tripod Camera in the World, Embodies all that is best in Camera construction. Unobtrusive, compact, easy to manipulate. L'sed with equal success by Novice and Photographic Expert. From i to 100 pictures can be taken without recharge. In constant use by Royalty, Travellers, Artists, Engineers, etc. Prices from £1 : 6 : 0 to £22 : 1 : 0. THE KODET. Specially designed for use with glass plates, but it can be employed with roll film by the addition of a Kodet roll holder, without alteration to the Camera. Carries 3 double plate holders, or 1 roll holder with capacity of 48 exposures. Possesses all the advantages of the Kodak as regards lightness, compactness, and simplicity. Prices from £3 : 3 : 0 to £4 : 10 : 0. SOI IO PAPFP The standard printing-out paper of the day. Gives clear *-<*V» w hites, exquisite tones, and high gloss. Ensures a most brilliant finish with the least possible amount of labour. In white, pink, mauve, and pense. MATTE SOLIO PAPER. * oast ^. *" * e .«~ u «* ^ glossy Solio, and is printed, fixed, and toned in exactly the same manner. R DO MinP PADPDQ F °r enlarging, or for printing by contact. Give oiwifiiLJE, rnrcKO. the finest and most perrnanent results> NIKKO PAPER Combines the soft effect of a platino or bromide tone ^* with a highly enamelled surface. PLATINO BROMIDE PAPER. ( ^ ^ pjw v giving the effects of Platino- type, but much easier to work. Soft grey and rich velvet tones. Manufactured solely by lie Materials Co. Ltd. Oxford Street, London, W. Paris : 4 Place Vend6me. Rochester, N.Y., U.S.A. Eastman Kodak Co. EASTMAN WRATTEN'S 'LONDON' PLATES. "Ordinary," 15°. " Instantaneous," 19°. " Drop-Shutter Special," 24°. The remarkable superiority of the " LONDON " PLATES over all rivals, as regards excellence of preparation, ease of manipula- tion, brilliancy, uniformity, and reliability of results, and ready adaptability to every department of the Photographic Art, is universally acknowledged. The "LONDON" PLATES were introduced seventeen years ago, and have been distinguished ever since for the high favour accorded them by the principal Amateur and Professional workers throughout the World. The sale of the "LONDON" PLATES is still largely on the increase, both at home and abroad, a fact which is the highest possible testimony to their value. More Genuine Prize Awards have been secured by results obtained on the "LONDON" PLATES than tin all other brands combined. The " LONDON " PLATES are employed by H. M. War Department, at their various stations, both at home and abroad ; the School of Military Engineering ; the Indian Government Departments ; Canadian Geological Survey ; various Observatories, both English and Foreign, and by the German, Russian, Turkish, and other Governments. May be obtained of any Photographic Dealer, or direct from WRATTEN & WAINWRIGHT, PHOTOGRAPHIC DEALERS, Apparatus and Sensitised Paper Manufacturers, and Sole Proprietors and Makers of the Celebrated "LONDON" Dry Plates. ILLUSTRATED CATALOGUE POST FREE. 38, Great Queen Street, Long Acre, London, W.C. Works:— WEST CROYDON, SURREY. Jt HP :"