Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 951)

Autofocus (viewfinder shooting)
Focus method
TTL secondary image-registration, phase-difference detection with the
dedicated AF sensor
AF points
191 points max. (cross-type AF points: 155 points max.)
* Number of available AF points, Dual cross-type AF points, and Cross-type AF points
vary depending on the lens used.
* Dual cross-type focusing at f/2.8 with center AF point
Focusing brightness range
EV –4 to 21 (with the center AF point supporting f/2.8, One-Shot AF, room
temperature, ISO 100)
Focus operation One-Shot AF, AI Servo AF, manual focusing (MF)
AF area selection mode
Spot AF (manual selection), 1-point AF (manual selection), AF point expansion
(manual selection, vertical/horizontal), AF point expansion (manual selection:
surround), Zone AF (manual selection of zone), Large zone AF (manual
selection of zone), Auto selection AF
Subject detection AF
EOS iTR AF setting (can recognize color information, faces, and heads)
* iTR: Intelligent Tracking and Recognition
AF Configuration Tool Cases 1–4, Case A
AI Servo AF characteristics Tracking sensitivity, Acceleration/deceleration tracking
AF fine adjustment AF Microadjustment (All lenses by the same amount, Adjust by lens)
AF-assist beam Fired by an external flash unit for EOS cameras
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