Depth Of Field Preview - Canon EOS-5D Instruction Manual

Aperture Value Display
The larger the f/number, the smaller the aperture opening will be. The
aperture values displayed will differ depending on the lens. If no lens is
attached to the camera, "00" will be displayed for the aperture value.
Depth of Field PreviewN
The exposure is locked (AE lock) while the Depth-of-Field Preview button is
pressed.
If the "30"" shutter speed blinks, it indicates
underexposure. Turn the <6> dial to set a larger
aperture (smaller f/number) until the blinking stops or
set a higher ISO speed.
If the "8000" shutter speed blinks, it indicates
overexposure. Turn the <6> dial to set a smaller
aperture (larger f/number) until the blinking stops or set
a lower ISO speed.
Press the depth-of-field preview button to
stop down to the current aperture setting.
The diaphragm in the lens will be set to
the current aperture so you can check the
depth of field (range of acceptable focus)
through the viewfinder.
f Aperture-Priority AE
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