Canon EOS-1D X Mark III Af Setting Manualbook page 30

Tracking sensitivity.
[Tracking sensitivity] is the parameter
that sets how the subject is tracked with
AI Servo AF or Servo AF when an
obstacle appears in front of the AF
frame or when the AF frame has moved
away from the subject.
Choose any [Case] and push
to select [Tracking sensitivity] and adjust level by turning
the Quick Control dial.
[Locked on: -]
[Responsive: +]
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button, then press
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