Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 475)

Subject Detection AF
You can specify whether to use Movie Servo AF if the subject set in [ : Subject to
detect ] ( ) is not detected.
Detect. priority
Movie Servo AF is used for automatically selected subjects within the area set in [ :
AF area ] ( ).
Subjects set in [ : Subject to detect ] are prioritized for automatic selection.
Detect. only
Movie Servo AF is only used for subjects set in [ : Subject to detect ]. Movie Servo
AF stops if no subject is detected.
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