Rabu, 11 Juni 2008

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

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