Canon EOS-1D X Mark III Af Setting Manualbook page 102

points becomes possible. Press the
Controls] assignment screen, and then select [Registered AF point].
Now when the button is held the AF will use the registered AF point.
4
Press the assigned button (selected in
stage 1) to switch to the registered
AF point.
AF point registration and usage is described above. Also,
for more advanced usage this setting can be combined
with [Orientation linked AF point] setting (described on
pages P. 94-99). Selecting the option [Select separate AF
points], from the [Orientation linked AF point] option
makes it is possible to register and recall AF points separately
for all three positions, vertical (grip top / bottom), and
horizontal as well as the remembered AF point for
orientation.
How to cancel registered AF point
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Press and
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102 102
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INFO button in the [Custom