A sprocket assembly for a motion picture projector and a method of threading and removing film from the sprocket assembly is disclosed. By selected configuration of the sprocket and the stationary sprocket guard, including aligner and keeper portions cooperating with the teeth of the sprocket, the film is inserted and removed by simply bending and lowering or twisting and lifting relative to the sprocket assembly.
Arthur C. Mueller - Niles IL Erwin E. Figge - Des Plaines IL
Assignee:
Polaroid Corporation - Cambridge MA
International Classification:
G03B 2302
US Classification:
352 72
Abstract:
A control system for a cassette-load movie camera having an automatic exposure control system. A variable neutral density filter adjusts the exposure control system to the film sensitivity, and a sensitivity range control adjusts the exposure control system alternatively for a range of high film sensitivities or a range of low film sensitivities. Cassette indicia automatically effect a filter setting and sensitivity range setting upon placement of the cassette within the camera. A switching system controls energization of the exposure control system in relation to energization of the camera drive motor.