Canon A-1 - Manual (Page 115)

Manual Override
You may have occasion to wish to cancel the
A-l’s AE capabilities to control exposure,
both aperture and shutter speed, by your­
self. This will be the case if you are using a
separate exposure meter, if you wish to
correct exposure in unusual lighting con­
ditions or in flash photography, or if you
want to control exposure for creative ef­
fects.
With the A-1, this is a simple process. Using
an FD lens, first disengage the_aperture ring
from the “A” mark. Set the AE mode
selector to Tv. The Av setting is useless.
Set the aperture by turning the lens aperture
ring, and set the shutter speed by turning the
AT dial. When you press the exposure
preview switch or the shutter button half­
way to preview the exposure, the data dis­
played in the viewfinder will be the same
as if the camera was in shutter-speed
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