Theatre Catalog (1946-47)

Prolonging Service Life of 16-mm. Prints Suggestions on Ensuring Long, Useful Life Needed for Profitable Operation For Films The useful life of a 16-mm. print is of interest to every film distributor, for it is inseparably associated with profitable operation. The circumstances that determine film condition or lead to damage may involve handling, storage, and projection. A print in service is no better than the worst treatment it has received. There is no single beneficial act, such as adjustment of equipment, humidification, leaning, or surface. treatment before handling, that alone will cure all film ills. Longer print life can be achieved only through proper treatment of film by all who handle it. Factors influencing service life of 16mm. prints fall into three general subdivisions: (1) Influence of laboratory processing. (2) Conditions in projection and attendant film handling. (3) Factors encountered in or controllable by film libraries. In general, the first of these factors cannot be controlled by the film distributor or exhibitor. Fortunately, most laboratories now produce prints of excellent quality, therefore, laboratory troubles are rare compared to those from other causes. Improper processing is generally avoidable by dealing with reputable laboratories having high standards of quality and precise control of processing. GREEN FILM Following initial drying of film in a motion picture laboratory (after treatment in a hardening-fixing bath) the gelatin structure of an emulsion contracts and is permanently changed. The hardening action still continues for a time as a further small amount of residual moisture is given up. While traces of excess moisture remain, the emulsion is “green,” relatively soft, and susceptible to the slightest scratch or abrasion. In projecting freshly developed “green” film, minute emulsion particles are scraped off, accumulate in the projector, and become hardened with heat and friction. If not removed, they cause excessive tension trom friction or abrasion of film passing through the gate, with consequent scratches, pulled perforations, and projector chatter. With time, green emulsion gives up residual moisture, and picks up traces of oil from the projector, becoming harder, surface lubricated, and jess susceptible to abrasion and tendency to form deposits in the projector. When properly aged, film will be nearly as scratch-resistant during the first projections as it will be after some time in service. Experience shows that stor 570 Frank Wine, Jr. Research Department, Ansco Division, General Aniline and Film Corporation age of new prints, without projecting for a week or more, is perhaps one of the most important acts by which film distributors can minimize damage to new films. PROJECTION Projection is the most important of factors influencing service life of 16-mm. prints. In the beginning, 16-mm. films were intended for amateur cinematography, and although they are now important as a medium for advertising, education, and entertainment, certain practices persist from the time when 16-mm. only meant “home movies.” To further the use of 16-mm. pictures without trained projectionists, a gospel of “anyone can run a projector” was propagated. This slogan is largely true, but any person who is to run a 16-mm. projector should be properly instructed, and should understand a few simple points if poor projection and film damage are to be avoided. FILM DAMAGE DURING PROJECTION Film damage during projection may result either from improperly maintained equipment and incorrect operation, or from the condition of a print when it is received from the distributor. Concerning projection, the entire matter is concisely summed up by J. A. Maurer in the following views: (1) No projector of reputable manufacture will injure -film if it is threaded correctly and if the projector is kept in proper operating condition. (2) Film can and will be damaged by any projector if it is not threaded correctly, or if the mechanism is not kept clean. | (3) Proper threading of film in a projector is not a matter of special difficulty, but damage can only be avoided by assigning responsibility for the care, cleaning, and lubrication of each projector to some reliable person, and by allowing only persons who have been This article is copyrighted by the Allied Non-Theatrical Film Association, Inc., under the title (second edition) of “Suggestions for Prolonging the Service Life of 16-mm. Prints,” and may not be requoted by others. It is reprinted here by special permission of the ANFA, Wilfred L. Knighton, executive secretary. properly instructed in the threading and control of: the projector to operate it. PROJECTOR MAINTENANCE In a properly designed projector, assuming the gate and all other film-guiding parts are polished and perfectly clean, film in good condition should run without any trouble or damage to the emulsion surface. This implies nothing more than plain cleanliness and avoidance of dirt in the projector. If dirt is allowed to accumulate, in addition to scratches which occur while film passes through the gate, prints are frequently scratched if one or more rollers are stuck and do not turn freely. The cause of this trouble is obvious, and it should never occur if equipment is properly maintained. Both tension adjustment and construction of projector gates are important. If all film supporting or guiding surfaces in every projector were perfectly smooth and constructed of a suitable glass-hardened material, there would be little trouble. But, unfortunately, some projectors have rather flimsy gates that are not. sufficiently smooth and hard, though the better machines are constructed to give excellent service. Obviously, excessive tension will retard free passage of film through the gate so that puli-down claws advance the film with excessive stress upon the perforations. This leads to nicked or pulled perforations, a starting point for further rapid wear and progressive deterioration of a print, leading to unsteady projection during subsequent showings. SCRATCHES IN PROJECTOR GATE Much film has been ruined by passing through projector gates that appear all right upon casual observation, but have minute scratches or abrasions of the metal, resulting from dirt and wear, or caused by ignorant persons who clean film supporting surfaces with a pin or other sharp metallic instrument. Minute scratches or abrasions of the gate that are hardly discernible may lead to chronic projection troubles because particles of emulsion are scraped from the film and deposited on the metal along with dust and dirt, forming deposits that further scrape and scratch any film that is run through the projector. Worn or abraded film-guiding surfaces should be replaced, and any part of the projector which comes in contact with film should be cleaned very carefully, using only non-scratching instruments of bone or wood. Metal should never be used. THREADING Bad threading and loops that are too large or small are common sources of projection trouble. If loops are too THEATRE CATALOG 1946-47