Canon EOS-1DX MARK II Settings Manual page 121

Synchronize initial AF point
used for auto selection AF with
manually selected point
When switching to [Auto selection AF] from
another [AF area selection mode], the setting
[Manual
AF starting with the AF point selected before
switching in [Initial
This is extremely effective for a series of
scenes when switching to other modes to
[Auto selection AF] for shooting.
Use the AF point from another mode
to move to auto selection
Set [Initial AF pt.
tab to [Initial
AF pt] activates auto selection
AF pt. AI Servo AF].
AI Servo AF] of the [AF4]
AF pt selected]
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