Canon PC1182 User Manual page 61

You are recommended to set the shooting mode to
and the exposure compensation setting to [±0] before
setting a custom white balance.
The correct white balance may not be obtained when
the exposure setting is incorrect (image appears
completely black or white).
Shoot with the same settings as when reading the
white balance data. If the settings differ, the optimal
white balance may not be set.
In particular, the following should not be changed.
- ISO Speed
- Flash
Setting the flash to on or off is recommended. If the
flash fires when reading the white balance data with
the flash set to
eye reduction), make sure that you also use the flash
when you shoot.
Since the white balance data cannot be read in Stitch
Assist mode, preset the white balance in another
shooting mode beforehand.
The camera will retain the custom white balance
setting that you record even if you reset the camera to
the default settings (p. 29).
(Auto) or (Auto with red-
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