Projection engineering (Jan 1932-Mar 1933)

NOVEMBER, 1932 Engineers want nationa technical standards for motion picture industry NATIONAL standards for all phases of the technical equipment and operation of the motion picture industry, from the lighting and acoustics of studios to the projectors and screens of picture houses, have been requested by the Society of Motion Picture Engineers. In a letter to the American Standards Association by Dr. P. G. Agnew, secretary of the Association, Alfred N. Goldsmith, vice president of the Radio Corporation of America and president of the Society of Motion Picture Engineers, asks for the development of uniform national standards to avoid the danger of confusion and waste resulting from the establishment of conflicting standards by different groups within the industry. If the request of the Society is approved, a technical committee representing all branches of the industry will be organized under the procedure of the American Standards Association. Topics outlined by Dr. Goldsmith for consideration are included in his communication, which follows : Some Topics Suitable for Consideration for Standardization Standardization projects, such as this proposed project on motion picture standards, grow logically step by step. Topics which initially seem of importance turn out to be not particularly susceptible to constructive and useful standardization ; other topics which would not be considered as suitable for standardization on preliminary consideration afterward develop into topics of major importance. In the following it is therefore possible only to consider the general field of motion picture activities (so far as they are of technological character) and to mention some of the topics which might be suitable for standardization. The list must be regarded as entirely tentative. Definitions The terminology of the motion picture field is confused at present. Such terms as "blimp," "zoom," "pan," "tilt," "projection angle," "wow," or "flutter," and the like, are used without any official recognition. This situation requires correction so far as is feasible. Film Measurement of characteristics of the base of the film, dimensions of the film and of its perforations, study of film shrinkage and permissible maximum shrinkage, photographic sensitometric tests, measurement and specifications of "safety film," standard width of film of various types, standard containers for film for storage and for transportation, together with methods of preservation of films (for archives, etc.) Studio The acoustic treatment and illuminating methods for studios doubtless would permit of a considerable degree of standardization, both as to nomenclature, measurement, and specifications. Great varieties of lamps are used which are designated, for example, as "spots," "baby spots," "rifle spots," and so on. Light-diffusing media are used which are known by a variety of colloquial terms but are not definitely specified, for example, in what is known as "oil diffusion," and presumably a wide variety of characteristics can be obtained under the same name. The acoustic characteristics of studios have not as yet been specified in any precise form in many instances, nor has measuring equipment for the purpose been adequately considered. Passing on to studio equipment, we find : Cameras The amount of significant noise produced in these devices at certain definite distances and in certain definite directions (in free space), the tolerances in the dimensions of the various working parts, the tensions and pressures in various parts of the mechanism, the dimensions of the magazines and of the magazine hubs, the take up tension, and numerous other characteristics of cameras require study for Seek Standard Definitions for "Blimp," "Zoom," and Other Terms 'Wo w 13 possible standardization. The mode of mounting the lenses, the possibility of standardizing focal lengths and apertures of lenses for motion picture practice, standardization of shutter aperture, definition of tripod arrangements and nomenclature for devices permiting moving shots (traveling trains, and the like), require consideration. Measurement of the effectiveness of camerasilencing inclosures is required. Recording Equipment Microphones, amplifiers, acoustic reflectors, recording equipment, and sound track measuring equipment fall under this heading. Numerous characteristics of these devices are measurable, might be specified to advantage, and may ultimately be suitable for standardization. Re-recorders These are used for the introduction of modification of sound effects, and are rapidly becoming an important part of the studio technic. They are used for recording from 35 mm. film to 35 mm. film ; and are now being produced as well for re-recording from 35 mm. film to 16 mm. film. The over-all frequency and volume characteristics of these devices, the amount of acoustic distortion that they produce, and certain other factors are of major importance. Photographic Printing Equipment Classification of types of equipment of this sort (continuous and step printers, optical reduction printers, contact printers). Permissible speed variation. Definition of maximum desirable operating speed. Specification of illumination of the printing surface. Laboratory Processes The development of film is now carried out in various ways by automatic machinery. The terminology requires study, and certain of the processes require precision measurement and definition. For example, methods of measuring developer concentration or speed, measurements of the effectiveness of processes for "hardening," or otherwise preserving film, and the like. Exchange Equipment Films, after being returned from the theater, pass to the exchange where they are inspected. Inspection methods have never been definitely specified or defined. Dimensions and mechanical specifications, as well as strength tests of reels and containers used by exchanges require consideration, both for nitrate and safety stock. (Concluded on page 16)