Sound track system for single or super 8mm films - uses two relatively shifted magnetic tracks allowing editing of sound after recording

摘要

The system includes use of two magnetic recording tracks running parallel along the film. One track carries the sound recording shifted by 18 frames w.r.t. the picture so that the picture may undergo the necessary intermittent movement, while the sound track moves steadily. The second track is used in conjunction with a second recording head which is shifted from the first head by the same standard interval of 18 frames. By editing between these two tracks, the appropriate sound signal and level may be added to the film, overcoming the problem of interruption of synchronisation when the film is cut. The viewer used in conjunction with the arrangement is provided with a magnetic head on the second track, not displaced w.r.t. viewing window.