Canon EOS 850
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The EOS 850 is an autofocus SLR for 35mm film introduced by Canon in 1988. The EOS 750 and 750QD are nearly identical, but add a popup flash. The EOS 850 was a very simplified EOS model, primarily meant to use programmed autoexposure, with no manual alternative. Film handling is motorized, and the camera requires a 6-volt lithium 2CR5 battery to operate.
A special "depth of field" metering mode is coupled with the (single) autofocus sensor: By half-pressing on the shutter release, the photographer selects two areas of the scene which are both meant to be in focus. The camera then determines the optimum focus distance, and stops down the lens to a sufficiently small aperture to achieve this.