Apparatus for establishing automatic exposure control modes in exchangeable lens camera

A lens exchangeable camera adapted for mounting an exchangeable lens having a diaphragm, a diaphragm presetting means settable to preset a diaphragm aperture size, and an aperture information transmitting means capable of transmitting respective first and second aperture information, said first aperture information representing that the diaphragm presetting means is preset at a minimum aperture size and said second aperture information representing each setting of the diaphragm presetting means other than the minimum aperture setting, said camera comprising:

• a program exposure control circuit for generating signals adaptable to automatically control the diaphragm aperture size of said lens and to automatically control the shutter speed under a given program in accordance with scene brightness;
• an aperture priority automatic shutter speed control circuit for automatically controlling the shutter speed in accordance with scene brightness measured through the diaphragm aperture actually stopped-down to the aperture size preset by said diaphragm presetting means;
• and
• change-over means for selective actuation of said program exposure control circuit and said aperture priority automatic shutter speed control circuit, said change-over means actuating said program exposure control circuit when said first aperture information is transmitted, and actuating said aperture priority automatic shutter speed control circuit when said second aperture information is transmitted.