Canon PowerShot S31S User Manual page 72

=_ P Tv Av
You can set the exposure and focus separately. This is effective when
the contrast is too strong between the subject and background or
when a subject is backlit.
1 Focus on the part of the subject on which you wish to
lock the exposure setting.
2 Press the shutter button halfway and press the ISO
button.
liThe =_ will display.
3 Re-aim the camera to compose the shot as desired
and press the shutter button fully.
To Release the AE Lock: Press anything except the A V, • or •
button.
o AE lock can also be set and released in =_ mode (p. 46).
oYou can use the FE lock when using the flash.
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