The optical system of the reputed FL 50mm F/1.4 standard lens was carried over into this new FD mount lens. Its high resolving power and high contrast delineation power are magnificent. Equipped with a coupling pin to the CAT System. SPECIFICATIONS: * Type: standard * Angle of view: 46 degrees * Minimum Aperture: F/16 * Closest Focusing Distance: 1ft 6in * Filter size: 55 *