Canon EOS 5Ds Instruction Manual page 91

S Selecting the AF Area and AF PointN
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 zones is used to focus.
61-point automatic selection
AF
The Area AF frame (entire AF area) is
used to focus. This mode is set
automatically in the <A> mode.
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