Canon EOS 6D Mark II Mode D'emploi page 109

One-Shot AF for Still Subjects
AF point
Focus indicator
f: Selecting the AF OperationN
Suited for still subjects. When you
press the shutter button halfway, the
camera will focus only once.
The AF point that achieves focus is
displayed, and the focus indicator
<o> in the viewfinder will also light
up.
With the camera in the default
settings and the metering mode set to
the evaluative metering, the exposure
setting is set at the same time the
focus is achieved.
While you keep holding down the
shutter button halfway, the focus will
be locked. You can then recompose
the shot if desired.
107