American cinematographer. (1943)

A.S.A. Prepares First Standards For Roll Film T HE American Standards Associa¬ tion has just completed the first standards ever prepared for the ten sizes of amateur roll film in most common use for snap shots. Eighteen dimensional standards with appropriate working tolerances cover the ten sizes, since one of the spool standards applies to 2 sizes of film and one of the film standards is used with 2 different spools. Nine of these apply to film spools and nine apply to the film itself and its backing paper. Two other photographic standards approved at the same time apply to the dimension of photographic paper — centimeter-size sheets and rolls, and inch-width rolls. Amateur roll film consists of a length of sensitized photographic film attached to a continuous strip of backing paper which is substantially longer than the film, as anyone who has ever developed his own film knows. The film and the backing paper are wound on a flanged spool to provide a unit which can be loaded into a camera and removed, after exposure, in daylight. This familiar article of commerce and sentiment and art is used, in a camera, to produce on the film strip a series of negatives, the position of each of which is governed by centering a series of num¬ bers—printed on the backing paper— within a small window in the back of the camera. The first daylight-loading roll film was introduced to the photographic world as early as 1895. It represented a major step in the field of amateur photography. The growth of film photography has progressed to a point at which substan¬ tially more than a hundred million rolls of film were being produced annually by the American manufacturers before war¬ time necessities compelled a reduction. Some of the film sizes included in these standards date back almost to 1895, al¬ though many minor dimensional changes have been made in them as production methods have improved and as camera designs have dictated more rigid toler¬ ances. In some cases, moreover, film lengths have been increased to permit more pictures to appear on a roll. No published data have been available throughout the years on the dimensions used by any manufacturer. Camera-mak¬ ers, consequently—and particularly those who were not also film-producers—had to rely, in designing new cameras, on their own measurements of spools and film purchased on the market. It is little wonder, therefore, that some cameras did not function properly, or that they per¬ formed satisfactorily with the film of one manufacturer and not with that of another—because of slight differences in the tolerances used by the manufactur¬ ers. Dimensional limits, minimum and maximum, had to be set up for the vari¬ ous spools in order to insure interchange- ability in cameras and also to provide adequate protection for the film against unwanted light. The films covered by the standards are those which give pictures of the sizes These standards, as finally approved, give the film manufacturers the assur¬ ance that, if the film conforms to the standards, it will function satisfactorily in cameras now in use. They also point the way for designers of new cameras and new accessories—and they will serve as a basis for other standards under con¬ sideration by other ASA subcommittees. The two standards approved for the dimensions of photographic papers cover centimeter-size sheets and rolls and inch- width rolls. The centimeter sizes are of relatively little interest to consumers in this country, but they are of substantial importance to the manufacturers doing export business to countries using the metric system. The standard covering dimensions of inch-width rolls gives spe¬ cifications for width, length, and splice allowance. This should be of definite importance to designers of the recording equipment and other apparatus employ¬ ing photographic paper in roll form. All of these standards are available from the American Standards Associa¬ tion, 29 West 39th Street, New York 18, N. Y. The 18 standards for dimensions of roll films and backing paper are pub¬ lished together in a single document en- New P.S.A. Index Helpful reference use of photographic magazines has been made possible through publication by the Photographic Society of America of a “Photographic Index.” Work of Jayne 0. Quellmalz, of 450 Madison Avenue, York, Pa., the “Index,” to be published in September, December, March, and June issues of the “P.S.A. Journal,” enables the amateur and pro¬ fessional photographer to locate out¬ standing articles in camera magazines. The “Index” presents 50 subject head¬ ings and authors’ names related to ar¬ ticles published in still and motion pic¬ ture camera magazines, professional journals, and trade papers. Many of the references are to the “Journal of the Royal Photographic Society,” a British publication. In many cases, im¬ portant articles are listed both by au¬ thor’s name and subject. for Amateur Roll Film Spools, Film, and Backing Paper (Z38.1.7-1943 through Z38.1.24-1943) for 50 cents. The two standards for photographic papers: American Standard Dimensions of Photo¬ graphic Papers—Inch-Width Rolls (Z38.- 1.5-1943); and American Standard Di¬ mensions of Photographic Papers—Cen¬ timeter-Size Sheets and Rolls (Z38.1.6- 1943) are available at 10 cents each. The Red Cross Needs Your Help — GIVE! 374 October, 1943 • American Cinematographer