Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 489)

Eye Detection
You can shoot with the eyes of people or animals in focus.
1.
Select [ : Eye detection].
2.
Select an option.
Disable
Eye detection is not performed.
Auto
The eye for AF operation is selected automatically after eye detection.
Right eye/Left eye
Gives priority to the selected eye for AF, after eye detection. If the eye
on the side with priority is not detected, the other eye is used for AF.
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