Canon EOS-1D X Mark III Af Setting Manualbook page 50

AF point expansion
[AF point expansion] is an AF area
selection mode that is best selected
when shooting sports.
For fast moving subjects that are
difficult to track with a single AF point.
Viewfinder shooting
[AF point expansion
(manual selection
Viewfinder shooting
[AF point expansion
(Manual selection,
surrounding points)]
Focus using one manually selected point assisted by 4 other
AF points (up, down, left, and right) or surrounding points.
Live View shooting
[AF point expansion （ ） ]
） ]
Live View shooting
[AF point expansion (Around)]
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