strip film of the conventional silver halide emulsion type is duplicated by optically projecting the images onto a high speed electrophotographic film in a system comprising a flow type camera having the original film and the electrophotographic film travelling at the identical film speed . the first station for the electrophotographic film is a charging station , followed by the projection slit , a toning station and a toner fixing station . the background density of the original film is measured by photometric means and compared with preset density standards , the resulting information being used to enhance the image produced on the electrophotographic film by varying the charge voltage level . charge level will control the amount of toner which adheres for a given time of toning .