Canon EOS 77D Mode D'emploi De Base page 101

One-Shot AF for Still Subjects
AF point
Focus indicator
While you hold down the shutter button halfway, the focus will be

locked. You can then recompose the shot if desired.
AI Servo AF for Moving Subjects
This AF operation is suited for moving subjects when the focusing
distance keeps changing. While you hold down the shutter button
halfway, the camera will keep focusing on the subject
continuously.
The exposure is set at the moment the picture is taken.

When the AF area selection mode (p.100) is set to Automatic

selection AF, focus tracking will continue as long as the Area AF
frame covers the subject.
AI Focus AF for Switching the AF Operation Automatically
AI Focus AF switches the AF operation from One-Shot AF to AI
Servo AF automatically if a still subject starts moving.
After the subject is focused in One-Shot AF, if the subject starts

moving, the camera will detect the movement, change the AF
operation automatically to AI Servo AF, and start tracking the moving
subject.
f: Changing the Autofocus OperationN
Suited for still subjects. When you
press the shutter button halfway, the
camera will focus only once.
The AF point that achieves focus is

displayed, and the focus indicator
<o> in the viewfinder will also light
up.
With evaluative metering, the

exposure setting will be set at the
same time focus is achieved.
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