Abstract: An interchangeable lens assembly for a camera is formed with a bayonet coupling affixed to the lens barrel with both being rotatable relative to an adapter shell. Upon attachment of the lens assembly to a camera housing, a detent pin is retracted from a fitted hole found in a radial flange of the adapter shell and the lens barrel is thereby rendered rotatable together with the bayonet coupling with reference to both the adapter shell and the camera housing while the adapter shell is held stationary relative to the camera housing during mounting and dismounting of the lens assembly.

Abstract: An interchangeable lens assembly for a camera including a lens barrel having a diaphragm mechanism mounted therewith, a bayonet coupling mechanism fixed on the lens barrel and adapted to be brought into engagement with a complementary coupling mechanism on the camera for releasably mounting the lens assembly in operative position on the camera, an adapter shell mounted on the lens barrel in rotative relationship relative thereto for establishing predetermined relative positioning between the interchangeable lens assembly and the camera, and a retainer mechanism adapted to be interposed between the adapter shell and the camera for retaining the adapter shell in fixed rotative position relative to the camera during mounting and dismounting of the interchangeable lens assembly. The lens assembly also includes a diaphragm presetting mechanism for transmitting signals representative of a diaphragm aperture between the lens assembly and the camera.

Abstract: In the photographic apparatus disclosed a long-exposure adapter is attached to a camera to lengthen the camera's shutter operating times. When the camera's light sensing system responds to a low illumination by setting the shutter time to B (infinite time), an operator shifts to the long exposure range. The adapter then responds to a high sensitivity sensor and a long exposure timing device in the adapter is adjusted for the low illumination. The adapter then operates the shutter release of the camera, which has been set to B to obtain long exposures.

Abstract: In an automatic flash camera having a lens with a rotatable focusing ring, a lens attachment coacts with the focusing ring to control the camera. In the attachment, a mounting arrangement detachably mounts the attachment to the end of the lens. An interconnecting arrangement, rotatably mounted on the mounting arrangement, engages the focusing ring to move therewith. A variable resistance system is mounted on the two arrangements and is varied by movement of the interconnecting arrangement relative to the mounting arrangement. The variable resistance system includes an adjustable member which is movable between a number of positions. In one position the variable resistance system exhibits one range of resistances corresponding to one type of lens when the interconnecting arrangement is moved. In other positions the variable resistance system exhibits other ranges of resistances each corresponding to lenses of other aperture ratios and focal lengths.