Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 869)

: Select AF Point, ( During Met)
During metering, you can select an AF point directly with the < > dial without pressing the
< > button. Setting this function switches the functions of the < > and < > buttons.
You can set exposure compensation or the aperture value by holding down the < >
button and turning the < > dial.
* 6: To set the direction for switching AF points with the < > dial, press the < > button when
the setting screen is displayed. [ Horizontal ] and [ Vertical ] settings for [ Direction: AF point
switching ] apply to Spot AF, 1-point AF, Expand AF area: (manual selection), and Expand AF
area: Surround, and [ Cycle through the zones ], [ Horizontal ], and [ Vertical ] settings for
[ Direction: Zone AF frame switch ] apply to Zone AF.
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