Amateur Photographer & Cinematographer (1935)

August 7th, 1935 auses IN these days, roll film is regarded as a negative material of almost universal application, and its use is by no means confined to the casual snapshotter. The serious photographer has now come to realise that negatives upon the best of modern roll films are equal, and in some respects superior, to those on plates, while the film has the obvious advantages of day¬ light loading, lightness and freedom from risk of breakage. In careful hands the roll film can be made to produce perfect nega¬ tives, but there are defects met with peculiar to this material, through non-observance of certain points which are dealt with in this article. Handling the Spool. It must be admitted that most of the defects met with on film negatives are the result of lack of care in handling the spools. Many photographers seem to fail to realise that even when the spool is tightly wound within its protecting paper, if the latter is not kept tight, or if the spool is exposed to very strong light, fogging at the edges is in¬ evitable. Care must be exercised to keep the film tight upon its core after the securing band has been broken, when loading the camera. If the operation must be done in strong light, only sufficient of the paper backing should be unrolled to permit of threading into the receiving spool. These may seem obvious precautions, but many photographers fail to observe them. Modern roll-film cameras are designed for easy loading, and to keep the film flat in the focal plane. Care must be taken when thread¬ ing the paper that it will run straight. Neglect of this means edge fog, or the film may become jammed, par¬ ticularly in the case of very small Thi amateur photographer a 6 CINEMATOGRAPHER o of Defective Roll-film Negatives The following topical article should be read by all users of roll films. Attention to the points dealt with will do much to avoid many of the defects seen in roll -film negatives. cameras where the space in the spool chambers is reduced to the minimum dimensions. These points apply with even greater importance to the highly sensitive panchromatic roll films. Some amateurs have a habit of twisting the spool in the hands after removing it from the camera. This does no good, as any properlymade camera will wind the film with sufficient tightness, while the very fact that the spool is taken from the camera in daylight is sufficient to cause the trouble, and tighter winding will not prevent it. The twisting of the spool has also the result of producing fine scratches across the negatives. Another point worth mentioning is concerned with the sealing of the rolled-up spool after removal from the camera. With most makes it is necessary to fold the pointed end of the backing-paper and tuck it under before the gummed strip for sealing can be secured. Many ama¬ teurs fail to fold the paper back far enough to make a tight join, with the result that the spool unrolls a little, and this is frequently enough to fog the film at the edges. The Camera. While not peculiar to roll film apparatus, the importance of a dust-free camera must be stressed. It must be realised that the mechani¬ cal action of winding the. film from one spool-chamber to the other is in itself sufficient to cause minute particles of celluloid or emulsion from the edges of the film to become detached. This in the course of time is bound to result in an ac¬ cumulation of dust. Frequent dusting of the camera, not forgetting the folds of the bellows, or in the case of a camera of larger size the use of a suction cleaner, is to be recom¬ mended. The interior should also be ex¬ amined from time to time to see whether all the parts are truly deadblack. The back ring of the lens and the edge of the inside of the camera back are frequently suffi¬ ciently bright or polished to cause mysterious fogmarks when photo¬ graphing in certain conditions of lighting. A good dead-black can be obtained from any dealer, and is easily applied with a small brush. The rollers over which the film travels should run freely, and the pressure plate which holds the film flat in the focal plane should be examined from time to time. If either do not function properly, the result will be scratched negatives. The Film in the Camera. When extending a folding film camera, the front should be drawn out gently, and not jerked out, as is the practice of some photographers. This not only imposes a strain upon the camera front, but also tends to draw the film out of the focal plane, with a bad effect upon the definition. When winding the film the camera front should be extended, and not closed. This is especially impor¬ tant if the camera is one of the small, compact type. Space has been so reduced that the folds of the bellows almost touch the film, and if wind¬ ing is done with the camera closed scratched negatives are inevitable. In any case, winding the film should be done slowly and steadily. Cameras need more care than is usually bestowed upon them. Very often expensive film cameras are to be seen upon the sands, quite unprotected from sun or sand. This is likely to cause trouble on one score or another. Attention to the simple precau¬ tions indicated in this article will do much to prevent most of the defects common to roll-film negatives. 127 9