Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 911)

Group C
Autofocusing with 191 points is possible. All the AF area selection modes are selectable.
: Dual cross-type AF point. Offers superior subject tracking and higher focusing precision
than other AF points.
: Cross-type AF point. Offers excellent subject tracking and high-precision focusing.
: AF points sensitive to horizontal lines.
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