Journal of the Society of Motion Picture Engineers (1930-1949)

380 ABSTRACTS [j. s. M. P. E. picture projector, and affords a convenient means for adjusting or repairing of elements associated with the light source. 1,786,027. Reproducing a Plurality of Photographic Sound Records on One Film. F. H. OWENS. December 23, 1930. A sound reproducing system utilizing a film which carries a multiplicity of sound records. A single light source is provided for all of the parallel extending sound channels on the film. There are separate light slits disposed in alignment with the channels recorded on the film and aligned with independent photo-electric cells so that all of the sound channels recorded on the film may be reproduced simultaneously. One sound channel may bear the record of one musical instrument while the other sound channels may bear the records of other musical instruments which have been officially recorded over different frequency ranges. Provision is made for adjusting the sides of each of the light slits by shutter members whereby the relative amount of modulated light received by each of the photo-cells may be adjustably regulated. 1,786,274. Synchronous Motion Picture and Sound Reproduction. F. VON MADALER. Assigned to National Vision-Tone Corporation. December 23, 1930. Discloses the design of a talking picture apparatus having sprockets and film feeding mechanism spaced at predetermined intervals and adapted to receive a film having markings thereon at spaced intervals to indicate the position in which the film must be mounted for initially feeding the film in proper position through the projecting machine. 1,786,301. Sound Recording and Reproducing Apparatus Utilizing a Film Having a Plurality of Sound Records. C. L. HEISLER. December 23, 1930. An apparatus for recording and reproducing sound from film where the sound is recorded successively in a plurality of tracks on the film. The film is moved longitudinally in opposite directions at substantially uniform speed. A narrow beam of light is projected on the film and the film-supporting device shifted transversely in order to effect reproduction or recording from the different sound channels. 1,786,368. Synchronizing Photography and Sound Recording. J. J. F. STOCK. December 23, 1930. A camera for coordinating the taking of pictures with the recording of music. A filmwinding shaft is provided in the camera. A device for feeding equal lengths of film through the camera during equal intervals of time is provided, comprising a continuous drive for the film-winding shaft. A friction clutch is connected between the drive and the shaft on which a pawl and ratchet arrangement is provided. An electro-magnet is arranged for actuating the pawl. The clockwork mechanism is provided for energizing the electromagnetic means in definite timed relation for operating the pawl in predetermined order for controlling the operation of the filmwinding shaft. The speed at which the film is advanced is automatically regulated in accordance with the production of music. 1,787,023. Camera and Method of Special Process Photography. J. F. SEITZ. December 30, 1930. Covers a method of making mats by exposing a film to two component parts of a picture simultaneously, one part photographing on one face, and the other on the other face of the emulsion or film. The film is developed and the picture projected on a screen and utilized in the making of a mat. In this manner photographs may be taken through different lenses