Canon EOS-1DX MARK II Settings Manual page 106

Set up steps
F i r s t , s e l e c t [Separate AF pts: Area+pt] f r o m
[Orientation linked AF point]. Next, select the AF area
selection mode and manually select an AF point location
for each of the positions (orientation): A) camera
Horizontal; B) camera Vertical with grip at the top; and
C) camera Vertical with grip at the bottom. The settings
will automatically be remembered. Now, for each of
these orientations it will automatically switch to the
select mode and AF points.
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