Af: Selecting The Af Mode; The Af Area - Canon EOS 5D MARK III Instruction Manual

AF: Selecting the AF Mode*
If focus cannot be achieved, the focus confirmation light < 0 > and AF
status indicator <_._ > in the viewfinder will blink. If this occurs, the
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.110).
If [1_11: Deep] is set to [Disable], the beeper will not sound when focus
is achieved.
After achieving focus with One-Shot AF, you can lock the focus on a subject
and recompose the shot. This is called "focus lock". This is convenient when
;ou want to focus a subject not covered by the Area AF frame.
AI Servo AF for Moving Subjects
This AF mode is suited for moving subjects when the focusing
distance keeps changing. While you hold down the shutter button
halfway, the subject will be focused continuously.
¢_ The exposure is set at the moment the picture is taken.
_, When the AF area selection mode is set to 61-point automatic selection (p.72),
the camera first uses the manually-selected AF point to focus. During
autofocusing, if the subject moves away from the manually-selected AF point,
focus tracking continues as long as the subject is covered by the Area AF frame.
With AI Servo AF, the beeper will net sound even when focus is achieved.
Also, the focus confirmation light <O> in the viewfinder will net light up.
AIFoCus AFfor Automatic S witching AFMode
AI Focus AF switches the AF mode from One-Shot AF to AI Servo
AF automatically if a still subject starts moving.
®_ After the subject is focused in One-Shot AF mode, if the subject
starts moving, the camera will detect the movement and change the
AF mode automatically to AI Servo AR
when focus is achieved in the AI Focus AF mode with the Servo mode
active, the beeper will sound softly. However, the focus Confirmation light
<0> inthe viewfinder will not light up. Note that focus will not be locked in
this case.
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