Using The Focus Lock - Canon Powershot A40 User Manual

Using the Focus Lock

The following types of subject may not be suited to
autofocus photography. Use the focus lock in these
situations.
¡ Subjects with extremely low contrast to the surroundings
¡ Subjects with extremely bright objects at the center of the
composition
¡ Subjects that are moving quickly
¡ Subjects through glass
Try to shoot as close to the glass as possible to reduce the
chances of light reflecting back off the glass.
Focus Lock Method 1
1
Aim the camera so that a subject at the
same focal distance as the main subject is
centered in the brackets in the optical
viewfinder or LCD monitor.
2
Press and hold the shutter button halfway,
and wait until the camera beeps twice.
Without releasing your finger, re-aim the
camera to compose the shot as desired
and press the shutter button all the way.
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