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

Aperture Display
The larger the f/number, the smaller the aperture opening will be. The
apertures displayed will differ depending on the lens. If no lens is attached to
the camera, "00" will be displayed for the aperture.
Depth of Field PreviewN
A higher f/number will make more of the foreground and background fall
within acceptable focus. However, the viewfinder will look darker.
If the depth of field is difficult to discern, hold down the depth-of-field
preview button while turning the <6> dial.
The exposure will be 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 the lens to the current
aperture setting. You can check the
depth of field (range of acceptable focus)
through the viewfinder.
f: Aperture-Priority AE
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