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

The increased use of magnetic production recording, together with a lack of suitable means of editing this material, has resulted in the development and use of equipment to make directpositive photographic duplicates of the magnetic recordings for use by film editors. Re-recording is being done in some studios directly from magnetic tracks, and in some, from photographic duplicates. Photographic duplicates may be either direct positives or electrical transfers to a photographic negative from which re-recording prints are made. The Signal Corps Studios, Long Island City, N.Y., have applied several modifications to standard magnetic recording systems, which provide improved operating efficiency as well as economies in time and material. These include facilities for: (1) stopping, reversing and restarting recorder, rerecorder and projector in interlock, and (2) silently changing over from record to playback, or vice versa, while running. Thus, errors in narration and re-recording jobs may be corrected without rethreading, splicing or blooping the film. Also, this studio has perfected a method for lip-synchronous production which makes use of 35-mm magnetic loops.20 The year 1950 has seen continued and extended use of nonsynchronous sprocketless-type magnetic recording equipments, particularly in the field of radio transcription. There have been described in the JOURNAL a number of schemes that have been developed to make these equipments operate synchronously with picture film for use in television and for cue-track recording 21,22,23 Last year also saw the use of lowshrinkage safety-base film extended to sound recording. By the end of the year practically all photographic recording was being done on acetate-base stock. 16-Mm Photography and Sound Recording Ansco has placed on the market a new 16-mm color duplicating film. Ansco's new film type 238 is designed for making duplicates with soft gradation color originals.24 The JOURNAL for January 1951 carries a complete bibliography of more than 600 items on high-speed photography covering all phases of the work.25 The Naval Ordnance Laboratory has developed techniques in the high-speed photography of underwater explosions. Pictures ranging from 2,000 to 3,000 frames/sec have been made of explosions of charges up to 1 Ib, at depths down to 2 miles.26 Early in 1950 a new 100-ft-film capacity, 16-mm single-system soundrecording camera called the "CineVoice" was introduced by the Auricon Division of Berndt-Bach, Inc., of Hollywood, Calif. It is available with a galvanometer for recording either variable-area or variable-density highfidelity sound track to SMPTE Standards. The camera weighs only 12 Ib and the entire equipment, including amplifier, microphone, cable, headphones, accessories and carrying case, weighs 34 Ib. It operates from either constant speed or synchronous motors. A portable power supply to drive the camera from an ordinary 6-volt storage battery is also available.27 Film phonographs embodying the fine motion and wide range inherent in the new magnetic recorders were provided for studio re-recording, dubbing and certain television applications. Magnetic J4-in. tape recorders gained popularity for many types of industrial and commercial purposes but were not generally accepted for motion picture recording. This lack of acceptance was due to such factors as lack of faith in the sprocket hole to insure synchronization, desire for standard speeds and desire for film that could be run 574 May 1951 Journal of the SMPTE Vol.56