Canon EOS 6D Mark II Mode D'emploi page 165

Servo AF for Moving Subjects
This AF operation is suited for moving subjects. While you hold
down the shutter button halfway, the camera will keep focusing on
the subject continuously.
When focus is achieved, the AF point will turn blue.
The exposure is set at the moment the picture is taken.
When [z5: AF method] is set to [u+Tracking] or [Smooth zone],
focusing will be continuous as long as the Area AF frame or Zone AF
frame keeps tracking the subject.
When the drive mode is set to <o> for high-speed continuous
shooting, the maximum continuous shooting speed is approx. 4.0
shots/sec. The pictures will be taken with priority given to the
continuous shooting speed.
When the drive mode is set to <i> for low-speed continuous
shooting, the maximum continuous shooting speed is approx. 3.0
shots/sec. The pictures will be taken with priority given to subject
tracking.
When an external Speedlite is used, the continuous shooting speed
will become slower. Regardless of the <o> and <i> settings,
the maximum continuous shooting speed will be approx. 1.7 shots/
sec.
Selecting the AF OperationN
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