Pentax Optio A40 Operating Manual page 36

Pressing the shutter release button
Press the shutter release button slowly in two steps. This allows for exact
focusing as well as preventing camera shake.
Basic way of shutter release
1
Press the shutter release button
halfway.
2
Lightly press the shutter release button until
you feel the click on your finger.
2
Confirm the focus frame on the
LCD monitor turns green.
Hold the shutter release button and wait
until the focus frame turns green. The
camera is in focus.
3
Press the shutter release button
fully.
Press it down slowly until the shutter is
released.
You can press the shutter release button all the way down (single step)
when Focus Mode is set to Standard (Autofocus) and One push PF in
the [A Rec.Mode] menu is set to On. (
This allows you to release the shutter at the right moment. The pictures
are taken as deep-focus (pan focus) shots.
34
The camera is
in focus.
The picture is taken.
p.114)
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