Canon EOS 50D - Manual (Page 176)

176
3 Custom Function SettingsN
C.Fn II: Image
C.Fn II -1 Long exposure noise reduction
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 of 1 sec. or longer. The
[On] setting may be effective for noise that cannot be detected or
reduced with the [Auto] setting.
C.Fn II -2 High ISO speed noise reduction
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. Change
the setting to suit the noise level.
0: Standard
1: Low
2: Strong
3: Disable
After the picture is taken, the noise reduction process may take the same
amount of time as the exposure. You cannot take another picture until
the noise reduction process is completed.
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.
With setting 2, the maximum burst for continuous shooting will decrease.
COP
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