C.fn Ii: Image/Flash Exposure/Display - Canon EOS 1D Mark III Instruction Manual

C.Fn II: Image/Flash exposure/Display

C.Fn II -1
0: Off
1: Auto
For 1 sec. or longer exposures, noise reduction is performed
automatically if noise typical of long exposures is detected. This [Auto]
setting is effective in most cases.
2: On
Noise reduction is performed for all exposures 1 sec. or longer. The [On]
setting may be effective for noise that cannot be detected or reduced
with the [Auto] setting.
With setting 2, if a long exposure is made during Live View shooting, the
LCD monitor will not display anything (no Live View image display) while
noise reduction is applied. During the noise reduction process, shooting is
possible. However, you will not be able to see anything on the LCD monitor
and in the viewfinder. Since you cannot check the focus and picture
composition, shooting is not recommended during the noise reduction
process.
With setting 1 and 2, after the picture is taken, the noise reduction process
may take the same amount of time as the exposure. During the noise
reduction, shooting is still possible as long as the maximum burst indicator
in the viewfinder shows "1" or higher.
C.Fn II -2
0: Off
1: On
Reduces the noise generated in the image. Although noise reduction is
applied at all ISO speeds, it is particularly effective at high ISO speeds.
At low ISO speeds, the noise in the shadow areas is further reduced.
With setting 1, the maximum burst for continuous shooting will greatly
decrease.
Long exposure noise reduction
High ISO speed noise reduction
3 Custom Function Settings
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