Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 488)

Caution
Tapping the screen to focus will focus with [ One-Shot AF ], regardless of the AF
operation setting.
If the subject's face is significantly out of focus, face detection will not be possible.
Adjust the focus manually (
) so that the face can be detected, then perform AF.
AF may not detect subjects or people's faces at the edges of the screen.
Recompose the shot to center the subject or bring the subject closer to the center.
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