Canon EOS-1D X Mark III Af Setting Manualbook page 60

Auto selection AF /
[Auto selection AF] / [
during AI Servo AF / Servo AF performs
AF using the entire AF area.
When using the optical viewfinder,
the camera will automatically change the
AF point within the up to 191 AF points,
and during Live View shooting, it is up
to approximately 90% horizontally and
100% vertically of the image area.
AI Servo AF/Servo AF with the entire
AF area used for automatic tracking.
Viewfinder shooting
AI Servo AF
＊ The frame will display when a face is detected.
When using the viewfinder and AI Servo AF, all AF points
are used, and during Live View and Servo AF, AF points are
selected from the entire AF area.
The AF points are arranged over a wide area, so it is useful
for capturing and tracking of subjects. However, depending
on the shooting conditions or if the subject is small, tracking
may not be possible, so caution is necessary.
+ Tracking AF
+ Tracking AF]
Live View shooting
Servo AF*
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