A Computer-Controlled Super-8 Projector

Abstract

Research conducted within Project C-BE (Computer-Based Science and Engineering Education) and other research has identified the need for random access computer-controlled motion-picture output at interactive computer terminals. The Kodak Supermatic 60 Super 8 magnetic sound motion picture projector was chosen for modification because it featured through-the-gate rewinding, auto-threading from cassettes, high reliability, and electrical controls. Mechanical modifications, included within the standard housing, involved adding four units (a fast-forward clutch with an actuator solenoid, a feed reel brake, a separate rewind clutch solenoid, and photodiodes in the film path to provide sprocket-hole motion signals). The projector is controlled by an electronic interface and control unit which receives its commands from the time-shared computer. The interface unit scans ASCII characters received from the computer and responds to control commands by performing the necessary operations without operator intervention. Search speed, forward and reverse, is about 450 frames/s and search accuracy is within four frames or better. Although the system is being used to teach observation skills in the area of child development, numerous other possible applications are envisioned. To the authors' knowledge, this is the only low-cost device to provide random access sound motion-picture output at a computer terminal.