An apparatus and method of producing a parallax stereogram, i.e., free vision stereogram, and particularly for the accurate registration of a plurality of film images in order to ensure stereographic reproduction. The images on a film strip are optically viewed to establish homologous points for each film frame image. In one embodiment two images are optically superimposed to establish a stereo base distance. Each film frame is marked in accordance with the homologous points or stereo base distance. The marking may be mechanical or optically generated. Each film frame is thereafter aligned or sensed while in an enlarger, the marks establishing the accurate registration of each frame. Each film frame is exposed onto a photosensitive material using a movable line grid. A lenticular screen is superimposed over the developed picture to form the stereoscopic photograph.