Canon EOS-5D Instruction Manual page 151

Custom Function SettingsN
3
C.Fn-01
You can change the function assigned to <0>.
0: Default (no function)
1: Change quality
After pressing <0>, look at the LCD panel and turn the <5> dial
to set the recording quality directly.
2: Change Picture Style
Press the <0> button to display the Picture Style selection screen
on the LCD monitor. Turn the <5> dial to select the desired
Picture Style, then press <0>.
3: Menu display
Gives the same function as the <M> button.
4: Image replay
Gives the same function as the <x> button.
C.Fn-02
0: Off
1: Auto noise reduction
For 1 sec. or longer exposures, noise reduction is performed
automatically if long exposure noise is detected. Setting this to
[Auto noise reduction] is very effective.
2: On
Noise reduction is performed for all exposures 1 sec. or longer. Setting
this may reduce the noise even for exposures which would not have been
noise detected/reduced at the [Auto noise reduction] setting.
After the exposure, noise reduction may take the same amount of time as the exposure time. While
the noise reduction is in progress, image playback and menu operation are not possible. However,
you can still shoot as long as the maximum burst indicator in the viewfinder shows "1" or higher.
C.Fn-03
0: Auto
1: 1/200sec. (fixed)
Sets the flash sync speed to 1/200 sec. in the aperture-priority AE
(Av) mode. (Against dark backgrounds such as the night sky, the
subject's background will look dark.)
SET function when shooting
Long exp. noise reduction
Flash sync. speed in Av mode
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