The Mitchell Recording Camera Equipped Interchangeably for Variable Area and Variable Density Sound Recording
C. R. Hanna · Transactions of the Society of Motion Picture Engineers · 1929
This paper describes a small sized sound recording adapter designed to fit a standard Mitchell moving picture camera. The need for apparatus which is fairly light and portable has been felt for some time. Devices have already been designed which record sound on the same negative as the picture arid these have proven a valuable supplement to recording apparatus using a separate film. This is especially true in portable work where small space is available and where quick setups have to be made.