An electrophotographic process and a system for preparing microfilm is provided in which use is made of a roll film including a photosensitive layer a thin film of organic photoconductive material on a film of polyester. A portion of the film is taken out of the roll and is conveyed to and stationarily held in a processing position where the film plane is vertical. A movable unit including a charger, an exposure window and a vessel of developing solution is moved parallel to the photosensitive surface which is thus held in place, in a direction which traverses the optical axis of a taking lens as well as in a direction parallel to the optical axis of the lens to effect an electrophotographic processing of the photosensitive surface while mainintaing the film plane vertical.