Canon PowerShot A720 IS User Manual page 34

I
Various Shooting Methods _ 99
_ Locking the Flash Exposure Setting
(FE Lock) []
[]See Functions Available in Each Shooting Mode (p. 206).
You can lock the flash exposure so that the exposure settings are
correctly set regardless of the composition of your subject.
To Release the FE Lock
Operate a button other than the ÷ or _ button.
The FE lock cannot be used when [Flash Adjust] is set to
[Manual].