Canon POWERSHOT G12 User Manual page 63

You can protect important images so that they cannot be accidentally erased
with the camera (pp. 28, 140).
Choose a Selectien Methed
..... Choose [Protect].
Press the MENU button to choose
[Protect] in the DE] tab, then press the @
button.
Choose a selection method.
Press the _v buttons or turn the _ dial
to choose a selection method, then press
the _,_ button.
Pressing the M EN U button will restore the
menu screen.
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