Canon EOS 7D Instruction Manual page 85

One-Shot AF for Still Subjects
AF point
Focus confirmation light
If focus cannot be achieved, the focus confirmation light <o> in the
viewfinder will blink. If this occurs, a picture cannot be taken even if the
shutter button is pressed completely. Recompose the picture and try to
focus again. Or see "When Autofocus Fails" (p.92).
If the [1 Beep] menu is set to [Off], the beeper will not sound when
focus is achieved.
Suited for still subjects. When you
press the shutter button halfway, the
camera will focus only once.
When focus is achieved, the AF point
which achieved focus will be
displayed, and the focus confirmation
light <o> in the viewfinder will also
light.
With evaluative metering, the
exposure setting will be set at the
same time focus is achieved.
While you hold down the shutter
button halfway, the focus will be
locked. You can then recompose the
shot if desired.
In the d/s/f/a/F shooting
modes, AF is also possible by
pressing the <p> button.
f: Selecting the AF ModeN
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