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

504 PATENT ABSTRACTS [J. S. M. P. E. and connected with the recording circuit for varying the gain in the recording circuit and marking the film in accordance with the gain variation by energizing the marking lamps. In reproducing sound from the film, the reproducer is provided with a relay-operated potentiometer for introducing in the reproducer circuit proper amounts of gain to compensate for the losses occurring in the recording potentiometer. The relays of this potentiometer are controlled by contact devices operating through perforations in the film where the markings occur or by light-sensitive cells responsive to the variations of light beams caused by the film markings when the beams are projected through the film. 1,785,262. Duplex Scanning Disk. C. F. JENKINS. Assigned to Jenkins Laboratories. December 16, 1930. A spot scanning system employing a rotatable scanning disk common to both spot illumination and spot cell pick-up. Light is passed through the scanning disk, the disk having apertures in alignment with the scanning elements of the scanning disk. As the light passes through both scanning disks, the light is rendered effective upon a light-sensitive cell. Both the incident and the reflected light passes through the same scanning disk thereby improving the efficiency of illumination while keeping the moving spot centered on the light cell. In the apparatus employed by the patentee a large apertured scanning member is disposed between the light source and the object to be scanned and a small apertured scanning member is disposed between the first scanning member and the light-sensitive device. 1,786,652. Dual Electro-Optical Scanning System for Television. RALPH V. L. HARTLEY. Assigned to Bell Telephone Laboratories, Inc. December 30, 1930. A television system wherein an image is produced by successively scanning groups of elemental areas of a field of view, an image of which is to be reproduced. Each group comprises two separate elemental areas which are scanned simultaneously. A light-sensitive device is actuated by the dual scanning system for producing a single photoelectric current having a component corresponding to the tone values of each of the simultaneously scanned elemental areas. 1.787.824. Tinting Picture Areas and Marking Sound Record of Motion Picture Film. JOHN G. JONES. Assigned to Eastman Kodak Company. January 6, 1931. A motion picture film where the picture areas of the film are tinted while preserving the sound record area thereof untinted. The film is advanced over a tinting roller with a flexible stencil partially wrapped about the roller to mask the sound record area of the film. The tint is applied to the stencil as well as to the picture areas of the film but the position of the stencil between the tinting roller and the film precludes the tint from reaching the sound channel portion of the film. 1.787.825. Motion Picture Film Marked to Designate Untinted Sound Record. LOYD A. JONES. Assigned to Eastman Kodak Company. January 6, 1931. A photographic film which is provided with a series of motion picture exposure areas and an untinted sound record area. The photographic film is tinted over the picture areas but is untinted over the sound recording area as the tinting interferes with the sound record. The tinted film when used in a dark room illuminated with the usual orange and red light has such an appearance that it is difficult to determine the location of the untinted sound track on the film. A designating line is therefore provided adjacent that edge of the film