Canon POWERSHOT A1000IS User Manual page 74

You can adjust the standard exposure set by the camera in 1/3-stop
increments in the range of -2 to +2.
Select the exposure
compensation.
Press the @ button, then use the ,_'_
buttons to select +0.
: Adjustthe Brightness.
While watching the screen, press the _
buttons to adjust the brightness, then
press the @ button.
After the picture has been taken, return
the setting to _ (zero).
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