Canon EOS-1D X Mark III Advanced User's Manual page 314

AF3
(1) Case 1
(2) Case 2
(3) Case 3
(4) Case 4
(5) Case A
(6) Tracking sensitivity
(7) Accel./decel. tracking
AF4
(1) Electronic full-time MF
(2) Lens electronic MF
(3) One-Shot AF release prior.
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