International projectionist (Jan-Dec 1948)

Simplex or similar rear-shutter mechanisms. However, I intended my suggestions to cover all types of projectors, front-shutter units as well as rear-shutter types, Motiograph, Brenkert, etc., as well as Simplex."] American Standard Definition For Photo 'Safety' Film The American Standard definition of Safety Photographic Film (Z38.3.1-1943) defines a photographic film which is no more hazardous than common newsprint paper, reports the SMPE. In order to be classified as Safety Photographic Film, a photographic film must be (a) difficult to ignite, (b) slow-burning, and (c) evolve a limited amount of toxic oxides of nitrogen during decomposition. The ease of ignition is determined by measuring the time of ignition after subjecting the sample to a uniformly maintained high temperature. The requirement for ease of ignition and the test method are the same as those specified by the British Standard definition of Cinematograph "Safety" Film (1939) and other European standards. The rapidity of burning and the method of measuring that characteristic are . also -the same as specified by the British. The toxic eases evolved when rjhoto Ansco Color Film Requires No Special Handling, Splicing Projectionists in various parts of the country have been receiving recently postcards from a film distributor which, in part, state: "This (Ansco) print is fine-grain release positive safety film. It is necessary that you make splices with Kodak Cement of either yellow or pink color . . ." Projectionists should not be flurried by these instructions. Ansco Color theatre release prints, unlike some other color prints, require no special handling. Nor is there any need for a distinguishing mark on these prints to indicate correct threading, as the emulsion is on only one side of the base and the image is oriented so that the procedure for threading is the same as for conventional black-andwhite film — that is, emulsion to light source. The base of Ansco Color film is of thefamiliar nitrate type and requires no special cement for splicing. Projectionists are well advised, however, to use the new common All-Purpose cement which is suitable for all types of film. The perforations on Ansco Color film are identical with those on the usual b-and-w prints. graphic films of cellulose nitrate are decomposed by heat are oxides of nitrogen, carbon monoxide, and hydrocyanic acid. Laboratory tests indicate that only oxides of nitrogen and carbon monoxide are evolved in sufficient quantities to constitute an appreciable hazard. These tests also indicate that photographic film does not evolve more carbon monoxide than does common newsprint paper when equal quantities of film and paper are decomposed in the same manner. The maximum quantity of oxides of nitrogen which can evolve when safety photographic film decomposes is limited by stipulating in the definition the maximum nitrogen (present as nitrate) content of the material. Fumes from photographic film that comply with this standard will not be significantly different from fumes evolved from ordinary newsprint paper decomposed under the same conditions. Photographic films made from materials for which this definition applies but which do not comply in one or more respects are not necessarily hazardous. For example, acetate film may fail to comply with the maximum nitrogen content specified in this definition and still not be significantly more hazardous than com- You Sell A Picture On a Screen... Make It the Best with f^nJe£ You invest heavily in a building, equipment, and personnel to sell one thing ... a moving picture on a screen. You can't afford to skimp on that. Your screen images must be the finest . . . critically defined, uniformly brilliant, pleasant to look at. One way you can be sure that your screen images are the finest is to use Bausch & Lomb Super Cinephor projection lenses, the standard of excellence in the theatre field. Bausch&Lomb Optical Co ., 616V St. Paul St., Rochester 2, N.Y. BAUSCH & LOMB OPTICAL COMPANY -w ROCHESTER 2, N.Y. INTERNATIONAL PROJECTIONIST September 1948 25