Abstract: An image-bearing medium (negative or positive) is located over and in close proximity to a light-sensitive film. During exposure, the film is moved in circular orbits parallel to the medium to cause spreading of image lines projected onto the film. To ensure uniform line spreading, the diameter of each successive circular orbit is increased toward a predetermined, maximum diameter, and the film is exposed during each orbit. The film is supported on a mobile table which is mounted, through a frictionless bearing, to a horizontal platform. The platform in turn is keyed to a vertical rotor. As the rotor is rotated by a drive motor, the table is caused to move in a circular orbit about the axis of rotation of the rotor. The diameter of the orbit, determined by the eccentricity of the axis of rotation of the horizontal platform with respect to the axis of rotation of the rotor is precisely controlled by a vertical rack and pinion mechanism.