 A smaller balance stripe existed to compensate the thickness of the recording stripe to keep the film wound evenly.Auricon and Cinema Products Corporation were two popular manufacturers of this type of camera, which were made obsolete by the takeover of video for news shooting in the late 70s.To edit single system magnetic film, it was necessary to first run it through a displacement recorder which would read the audio and re-record it backwards 24 frames behind the point where it was recorded.