Canon EOS-1D X Mark II DSLR Camera (Body Only) - Manual (Page 92)

S Selecting the AF Area and AF Point
92
AF point expansion (Manual
selection, surrounding points)
The manually-selected AF point < S >
and the surrounding AF points < w > are
used to focus.
Zone AF
(Manual selection of zone)
One of nine focusing zones is used to
focus.
Large Zone AF
(Manual Zone Selection)
One of three focusing zones (left, center,
and right) is used to focus.
Automatic selection AF
The Area AF frame (entire AF area) is
used to focus.