The Cine Technician (1939)

189 T II E C 1 N E-T K < II \ I < I A X I > -Jan., r. TECHNICAL ABSTRACTS— {continued from p. 188) Third Dimensional 16 mm Stereoscopic motion pictures movies in which a real illusion of the missing "third dimension" of depth is given — have received the attention of many researchers, professional and amateur. Some oi their schemes have worked ; others have' not. But the goal of producing moving pictures which will give a scene the same roundness and depth the eye perceives continues to hold endless fascination. ( )ne ol the mi ire reci nt and im ire succ researches into this field 1ms been conducted by J. Kinney Moore, S.A.C. member and maker of "ISiite Life," which won a special award for special effects camerawork in this magazine's 1936 Amateur Movie Contest. Moore's experiments, made on 16mm. Kodachrome film, successfully capture the third dimension and combine it with natural colour to produce results rarely, if ever, show on the screen before. Thq principle underlying any perception of depth, whether photographic or merely visual, is simple. Our eyes .in placed side by side, approximately l)7s inches apart. Each eye therefore sees the view from a slightly different aii'_de ; in effect, the right eye sees slightly '"around" the right side of an obje t, while tic left eye similarly partly around the opposite side. In our brain, the two images are combined into on and this two-eyed vision gives us our perception ot * I ■ 1 > t ■ i and roundness. If one eye is put out even merely closed —things appear as flat as a photograph, and one finds it almost impossible to judge depth i >r distance accural ely, The camera is necessarily a one-eyed instrument. It cannot, therefore, give anything but a flat one-eyed picture. Evi ry system ot sten scop c photograj^hy or cinematography depends on making in some fashion two separate pictures of a scene, each of which represents whal one eye would see. and then showing each eye its proper picture while preventing it from seeing the other eye's \ |e\\ . Moore gets his two films by coupling two Cine-Kodak Specials together. His two cameras are mounted on a special base, which he built himself. This base is hinged alone; its centre line, not only to allow the left-hand camera to he swung (dear that the right-hand one may he loaded conveniently, hut to permit th ■ cane ras to he "toed in" so that both are centred on the same objei I usually the most distant important object in the scene. Each camera is driven by its own clockwork mechanism, but the two are kept in step with each other li\ means of a mechanical coupling. The one-picture-perturn "trick crank" of the camera is removed. In its place is put a sprocket. The sprockets, in turn, are both connected through a chain belt to a common shaft. Thus it is impossible for one camera to run without the other. In practice. Moore often uses hut one camera's motor to drive both. Projection is by two Ampro projectors connected through a similar chain and shaft coupling. Tn this case, the knobs used to turn the projector's mechanism in threading has been removed and the sprockets substituted, while the knobs have been replaced at the end of tic coupling shait. In use, both projector motors are employed for driving. I. h projector is fitted with a standard Eastman l-'ola screen Light polarising filter. The two polarisers are -sed" or placed with their polarising plan : es to each other. The house is given spectacles, the lens of which also cro.ised pola screens. Thus each eye can see only the ilim 'e projected by the projector whose polariser is parallel to the polarising lens in front oi that eyc\ and cannot s se the other imagi pi through the polarise] . American Cinematographcr, September, i Report of the Snh-Committee on Perforation Standards The Sub-Committee has investigated the possibility of adopting the S.M.P.E. standard perforation for negative film, and has comi to the conclusion that various factors, especially the stock of background films, makes it impossible to use the S.M.P.E. standard perforation universally. The Committee now proposes that the rectangular perforation proposed by Howell and Dubray in 1932 adopted as the standard perforation tor both negative and positive. This perforation would operate satisfactorily on all apparatus designed for the Bell & Howell perforation, and should give little or no trouble on apparatus designed for the S.M.P.E. standard perforation. — S.M.P.E. Journal, October, WE SERVE THE INDUSTRY BY PROVIDING THE ONLY EXCLUSIVELY TECHNICAL FILM EMPLOYMENT AGENCY LICENCED ANNUALLY BY THE LONDON COUNTY COUNCIL Accurate records oi technicians available: camera, sound editing and cutting, art, stills, assistant directors, continuity girls, all grades of laboratory workers From . . . A.C.T. EMPLOYMENT BUREAU 145, WARDOUR STREET, LONDON. W.l Phone: Cerrard 2366