In the disclosed motion picture system a shutter drive control circuit renders it possible to operate a rotary shutter in various exposure control modes including a mode in which rotation of the shutter is stopped for each long exposure of motion picture frame, the system can defer release of the shutter to the exposure aperture closed position pending completion of a picture frame exposure in any of the modes. The system terminates the preceding manual actuation of a shutter trigger when the taking of the particular picture frame is in progress.