Canon PowerShot S2IS User Manual page 107

While pressing the shutter button halfway, press the
~
button .
• The flash pre-fires to acquire the exposure value required for the subject,
and
*
appears on the LCD monitor (or viewfinder).
• Each time you press the
00
button, the flash exposure locks at the
required intensity for that composition.
Recompose the image and shoot.
1
Select [Flash Adjust] from the
[[!J
(Rec.)] menu.
See Sele"cting Menus and Settings (p. 73).
Use the ..... or
~
button to select [Auto] or [Manual] and
press the MENU button.