Canon EOS-1D X Mark III Advanced User's Manual page 317

AF3
(1) Movie Servo AF speed
(2) Movie Servo AF track sens.
AF4
(1) Electronic full-time MF
(2) Lens electronic MF
AF5
(1) Subject tracking settings
(2) Lens drive when AF impossible
(3) Limit AF methods
(4) AF area selection method
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