Amateur Photographer & Cinematographer (1933)

August 16th, 1933 of a building, tree, or even a hat or book. The lens hood is best, and wise photographers will use one on all occasions, as the quality of the negative is improved thereby. The best materials for rendering contre-jouy effects are the double-coated films and plates, such as the various “ chrome ” films and Ilford hypersensitive plates (backed). These have a " backing ” which prevents the scattering of bright lights in the emulsion, thus doing away with ‘ ‘ hala¬ tion,” or the fuzzy effect which sometimes occurs when brightly-lit parts of the picture come up against darker tones. If we examine the washing in “ Washday ” (taken on double-coated film) we shall see that the texture and edges of the materials are well rendered without a trace of this fuzziness. On ordinary film they would probably have been a hopeless blur. It is this quality which makes these double-coated materials well worth their slightly greater cost. The exposure for back lighting should be greater than for other forms, as we are dealing with wider contrasts, and are The AMATEUR PHOTOGRAPHER n & CINEMATOGRAPHER a photographing the darker side of the subject. I recom¬ mend double the usual exposure. The increase may bebrought about either by a longer time of shutter opening, or by using a larger lens stop. Also, because of the greatercontrast, development should be curtailed, not more than two-thirds of the normal time being given. Provided that the same precautions are observed, we can use a back lighting for indoor subjects, such as still life and portraits. With portraits, it is advisable to have a certain amount of front or side lighting in addition, as otherwise the face will be too dark, and a silhouette will result. When the model has fair hair a halo effect isproduced, which is very pleasing if carefully managed. The extra front or side lighting may be obtained either by the use of lamps (smaller in value than the main back light) , or by the use of white reflectors. White sheets or news¬ papers answer quite well, and should be suitably placed soas to throw back some of the light from the main source on to the front of the subject. How to Wash a Film By CLARENCE PONTING. ALTHOUGH the amateur finds no difficulty in washing glass negatives, when it comes to a strip of roll film he is often in difficulty. And yet, this flexible and eel-like medium is, if anything, more easily dealt with than the glass negative. The whole thing simply comes to this, do you still labour under the impression that running water is necessary for the washing of negatives ? If so, th m films may present a certain amount of trouble. As has often been stated in this journal, negatives can be effectively washed by soakings in repeated changes of water, and that is how a series negatives washed, required of roll film should be All that is to effect this is a deep bowl, such as can be borrowed from among the kitchen china, and one pin. After fixation, the length of film should be pinned together by placing the ends so that they over¬ lap by about one quarter of an inch, when they are secured by a pin thrust between the middle. It is advisable, to prevent accidental scratching of the nega¬ tive image to place the negative side inwards when Hooping the film into position for pinning together. The film is then lowered into the bowl, which has been nearly filled with water, or sufficient to cover the him, allowing an additional inch in case it should rise whilst soaking. The water is changed at intervals of ten. minutes, making six changes in all, after which all the hypo which might cause impermanence of the negatives will have passed away. In between the second and third soakings, the him may be passed through a weak solution of hydrochloric acid and water, which will clear off any scum due to develop¬ ment in a solution made up with hard water instead of rain-water. This bath renders the him beautifully clear and transparent, especially where chalky deposits are found in the tap water, and is responsible for those unaccountable hnger-prints sometimes found on this class of negative. Trade developing people wash their hlms by suspension in deep tanks, in which the heavier hypo solution dissolves out of the emulsion and drops to the bottom of the re¬ ceptacle. Films can be washed in this way by suspension in a tub of water, pinning one end to a cork, and attaching to the other a heavy paper-clip, or other type of weight. Another effective method of washing a strip of film is to employ the family bath. Run off about a foot of water, into the bath, fix a couple of letter-clips to the film, one at each end, and lay the length of film fiat along the bottom. If, as is likely, the film rises slightly, it may be left to soak for a quarter of an hour before changing the water, and repeating the operation thrice more. Some films will not rise in the above manner when laid out fiat, but can be made to do so by pushing the clips towards each other for an inch or so. The film may also be laid on its side in the bath water, especially when clips are used, for the thumb-springs will retain it in this position. A change of secretary is announced at the South London Photographic Society, Mr. A. G. Winter having resigned this position. The new Secretary is Mr. Dennis E. M. Wright, and all communications should be addressed to him at 12, Marmora Road, East Dulwich, S.E.22. 163 29