Canon A650 IS - Manual (Page 115)

Various Shooting Methods 113
z 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).
z 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 or is recommended. If the
flash fires when reading the white balance data with
the flash set to
, make sure that you also use the
flash when you shoot.
z Since the white balance data cannot be read in Stitch
Assist mode, preset the white balance in another
shooting mode beforehand.
z Recorded white balance data will be retained even when
the camera's power is turned off.