Still photographic or movie camera

摘要

A camera having a forward lens unit including a displaceable lens for providing a variable focal length, a film plane, a base objective having a fixed focal length, and an aperture diaphragm between the displaceable lens and the film plane together with automatic drive means for displacing the base objective axially in direct proportion to the diaphragm stop of the aperture diaphragm to thereby shift the image plane defined by the forward lens unit and the base objective and provide a substantially constant circle of diffusion at the film plane.