Assistants' notes: Celluloid Facing; Photography with the Royal Engineers; Ply Wood

Celluloid Facing.

           PHOTOGRAPHIC miniatures, which are so popular with the working-classes, are easily made; the important factor is the time taken up. By means of the card repeating back four pictures are made on a quarter-plate. Sometimes the original requires the background painted out with Chinese white, or a few touches put in with lamp black water-colour to make a bold effect. Of course, these touches are sponged off after making the negative, which should be on the contrasty side. Four (pictures are made on one piece, of glossy paper to give sharp detail, and then coloured by dyes. Celluloid facing gives an enameled appearance, and by its attractiveness helps the ale. For cementing without hot rollers use 4 parts methylated spirit, 1 part amyl acetate. Do not increase the amyl acetate unless the celluloid is thick. This is best for gelatine papers, such as glossy P.O.P. and bromide. Do not use this with collodion papers, as it dissolves the image. Cut a piece of celluloid a little larger than the print, put a few drops of above in the middle of same, then press from the centre all round outwards, in contact with blotting-paper. By making the facing little larger than the print the excite cement reach the blotting-paper and does not get on the face of picture spoiling the high gloss. With a little practice the right number of drops will be found, and no air bells formed. Major's cement, which is gelatine dissolved in glacial acetic acid, is more suitable for collodion papers, is slow in working, and if you use this cement for glossy P.O.P. and the picture should slip in the pressing down, you will find the acid has softened the image and the movement blurred the picture. Collodion papers are not suitable for dye work. - BURLINGTON.

Photography with the Royal Engineers.

           ACCOUNTS of the part that photography has played in the war have so far been written principally in terms of aircraft observation While no doubt this branch has employed more men and material than any other, and has been both organized and advertised in the energetic and efficient way characteristic of the Air Force, there has been a vast deal of photography done in connection with other departments that should not be lost sight of in considering photographic war-history. The work of official photographers of a kind hat used to be done by war correspondents is, of course, also well known as is the development in radiography; but the photography can-led out by men of the Royal Engineers has been not only extensive and varied in character, but it has not met with the recognition that its importance and quality deserves.
           ACCOUNTS Of work that takes the operator well up into the danger zone is the making of panoramic views of enemy trenches and territory. Then there is "sound-ranging." This is a marvelously ingenious and scientific method of locating enemy guns very exactly. The apparatus was invented by a Frenchman and improved by us, and as the Germans have never succeeded in capturing an instrument nor in remotely approaching the idea in efficiency, this has been a great factor in our success. The part of the photographer in this branch calls for decreasing knowledge and skill as the instrument is improved, but it calls for mention in a record. This is only one of the many rapidly growing activities of a Field Survey Battalion. These unit's are more generally known in the Army under the concise and expressive name of "Maps."
           Enormous quantities of maps are plotted, drawn, and printed "in the field," and the photographer has his share in reproducing them to various scales, both on wet and dry plates, including, of course, panchromatics. Many of the workers are old “Ordnance Survey” men, but they are not now by any means in the majority. Besides the operators there are men who print the line negatives on to zinc plates for the lithographic printers, and those who print in special variable details by true-to-scale processes. Then there are the highly skilled "glass engravers," as they style themselves, or "negative-scratchers," as would-be humorists call them. Their work, delicate and tedious, done principally with a finely sharpened needle and a magnifying glass, is at its best compared with ordinary commercial retouching as the latter is to scene-painting.
           In a published account of the success of the Intelligence Corps were mentioned, in passing, the expert photographers as assisting in its work. These also are men of the Royal Engineers. The field of photography even here is varied enough to try the skill of the best. Copying and printing in large numbers portraits of suspected persons is only one small item. These often have the unmistakable appearance of being already copies of the third or fourth generation - if I may use that expression and badly done at that; so that to make good printing negatives to give useful results is not always easy. Copying documents and posters to be used in convicting enemy officers of illegal executions is work that one could take pleasure in, notwithstanding the weird colours and crumpled conditions of some of them. Photographing parts of captured mechanism for various departments is frequently required, and even work of very technical and experimental character is successfully coped with, although it will be recognized that material, when it arrives at the place of use, often has already had a long history of careless handling and bad storage behind it, and, therefore, cannot always be considered as of all category. - D. CHARLES.

Ply Wood.

           THREE-PLY wood is now available for photographic purposes, the various restrictions having been - withdrawn, and is a useful material for either carbon transfer or for mounting enlargements. Card-board mounts require a further hacking of wood when framed, whereas a picture mounted on ply wood would go straight into the frame, having a nice appearance at the back; so if we take this advantage into account the price will compare favorably with card-board. Ply wood is made in various woods, up to seven-ply for special use, but for mounting purposes three-ply birch, which can be had "free from knots one side," 'will answer studio requirements. The albumen in the wood, by steam treatment, is made somewhat insoluble; though some call it "waterproof three-ply,” it certainly is less absorbent than the ordinary sort, and less liable to wood-worm. It does not split like ordinary panels, is superior to canvas, as holes cannot be knocked through it, can be got any size and cut any size, stretchers are dispensed with, and is the material the old masters would have welcomed with open arms. - BURLINGTON

Practicus In The Studio: Printing Processes For Portraiture.

           I find that nowadays people are rather apt to get into a groove over their printing methods and apparently forget that any other process exists except that which they happen to be working. It thus occurs to me that a brief review of the Different printing media at present available, with notes on the characteristics of each, would be of service to those who wish to vary their work.
           The uncertain character of daylight in Great Britain has made bromide and gaslight papers very popular, and an overwhelming proportion of portrait work is now produced upon them, but thanks to the almost universal supply of electric current, we are not now altogether dependent upon daylight for what may be generally classed as "printing out" as distinguished from developing processes.
           The quality of the negative is an important factor in the production of the print, and only a small proportion of current negatives would yield even a passable result upon the old albumenized paper which for many years was almost exclusively used, so much so, in fact, that a print was hardly regarded as a "real" photograph unless it was made upon it By reason of the quality of the negative required, and because it was impossible to produce it by modern factory methods albumenized paper is now only a memory, and it is impossible to procure even a small quantity through the ordinary channels. Hence it is unnecessary to touch upon it otherwise than by way of reminiscence. Bromide paper in its various grades has taken its place, and I therefore put it first upon the list as being the process for the million, or that proportion of it who practise photography.
           Although in such general use, few portraitists fully appreciate the wonderful variety of surfaces, speeds, and character of emulsions which are available. I cannot fairly allude to any specific makes by name, but will be content to refer my readers to the advertisements in the B.J. Almanac, and the advertisement pages of the weekly Press. Bromide papers may roughly be divided into several groups, although these somewhat overlap each other. We may divide them by speed, that is to say, the time necessary to produce a print from a given negative by a given illumination; by the degree of contrast which can be obtained from the same negative by the surface texture, and by the colour of the paper base itself apart from the image. Thus we have "slow" and "rapid" papers, hard or contrasty, and soft, rough, smooth "platino matt," "satin," and glossy, these giving a range from rough drawing paper to a surface like glass. In many cases certain grades come into two or more of these classes. Thus we may have rough rapid, smooth rapid, hard cream and soft cream, and the same in white. In this great variety lies one of the principal advantages of bromide paper, for there is hardly a negative which is capable of being printed at all for which a paper which will give the best result cannot be found. Many printers use only one variety of paper, and trust to their skill in exposure and development to produce even results from all classes of negatives, but from experience I can assert that a very ordinary worker can produce a better result upon "hard" paper from a flat negative than an expert can upon the average kind. Therefore I advise every printer to have by him a small stock of special papers, so that he can at once select the quality necessary for exceptional densities of image. While not recommending this course to he carried too far and to encumber one self with too many kinds, I would point out the influence of colour and surface in certain cases. Suppose that we have a hard, chalky negative; we can use for this a "cream crayon soft" paper. This not only reduces the contrast of the image but tones down the glare of the whites, while the slightly rough texture gives further aid me direction. With a very soft negative we may choose a satin surface paper, that is, one with a semi-gloss, which gives a richness to the shadows. A full gloss paper would be even better, but for high-class -work a glossy surface is rarely acceptable. Further modification may be obtained by toning the image to a sepia colour, a course generally advisable with harsh contrasts, as brown and white usually gives a softer result than black and white when both print are of the tame quality. I strongly the practice of toning bromides irrespective of quality; every day thousands of prints which are of fatrly good quality in black and white are spoiled by being converted into poor, flat, rusty sepias. If I have the slightest doubt as to the resulting tone of a print I would- leave it in black and white, and if the order were for sepia prints I would ask permission to submit a black and white print when sending the proofs.
           Gaslight papers closely resemble bromide in the points I hare already mentioned, so that it is not necessary to deal with them at length. I should like, however, to say that besides the "contrasty" qualities which are most used, are special kinds which, though very slow in action, walls give splendid results from dense negatives. These papers require a very strong light for printing, several fifty-candle-power lamps being needed in the printing boxes.
           Gelatino-chloride or P.O.P. was not o long ago almost universally used for portrait work, but is now little in favour, especially among the cheaper class of studios. A few good class firms still find that the warm tones so easily obtained upon it are acceptable to their patrons, and wisely adhere to it. Certain warm browns and reddish tints closely approach the delicacy of carbon, and will always be popular, but the purple black tones are now quite out of fashion, P.O.P. requires much greater cart- and cleanliness in working than bromide, which may account for the latter superseding it.
           Self-toning papers, which are mostly collodio-chloride, possess many advantages, although they are the slowest of the printing out sort. This defect may be largely overcome by employing an enclosed arc for printing, when the time in much shortened. A great range of tones from warm sepia to a blue-grey may be obtained by variation of the strength of the hypo bath and for the grays a preliminary soaking in a solution of common salt. Matt and glossy surfaces and white and cream bases are available in this class of papers. A variation of tone may be obtained by using a platinum toning bath as employed in the doable toning of ordinary collodio-chloride paper. I hare used much of this paper, and find that the prints stand very well. Some, which are fifteen or sixteen years old, seem quite fresh. Self-toning gelatino-chloride is also made, but I have not found so good a range of colours with them as with the collodion. Moreover, they cannot be dried by heat, as the latter can. Some few photographers have used what is termed salted paper for large work. This has to be prepared at home by coating drawing paper with a solution of chloride of ammonium or even common salt, and floating upon a bath of nitrate of silver. The prints may be fixed without toning, or they may be toned in any of the gold baths used for P.O.P. Strong negatives are required, as the image is inclined to be rather dull as compared with that on an emulsion paper. The surface is very agreeable, and with suitable subjects the results are highly artistic. Platinum printing like carbon stands in a category of its own, and occupies the first place with those photographers who put quality before cost. It is, next to ferro-prussiate, the simplest of all printing processes, and is not only pleasing but permanent; it is actually a "thing of beauty and a joy for ever." Platinum papers can be obtained in rough and smooth surfaces, end on white and cream bases. As there is no practically useful method of toning, special papers and solutions are prepared for black and sepia prints respectively. One important quality of platinum prints is their absolute flatness when finished; as there is no coating either of gelatine or collodion there is no risk of curling, and if attached by one edge to a mount they will lie close to it no matter what the condition of the atmosphere may be. It should be clearly understood that the word "platino," when applied to bromide paper, refers to nothing but the appearance of the surface. There is no platinum in the coating, and the image is no more permanent than that on ordinary bromide papers. Carbon printing is unique as regards the great variety of colour and surface in which prints may be produced. Although in portraiture only two or three are commonly used, such as sepia, red chalk, and warm black, at least fifty varieties of colour, including reds, blues, greens, browns, grays, and many others, and a score of different weights and surfaces in the transfer papers are regularly supplied. So that it is possible to make carbon prints which closely resemble those by any other photographic process; and, needless to say, all are absolutely permanent. It is worth noting that, in spite of war restrictions, the price of carbon materials has shown but little increase in price. Many are deterred from attempting carbon printing by the idea that it is very difficult, but this is not the case if ready sensitized tissue be used, and if the work be carried out systematically it is little more troublesome than P.O.P., and the extra price obtainable will amply justify the additional work.
           I have carefully abstained from giving working details of any process, us this has been done over and over again, out in case of any difficulty, any desired information will be given through the usual "Answers to Correspondents" column. My object has been to point out what materials photographers have to hand for the production of such prints as may be needed for any claw of business.

PRACTICUS.