Canon EOS-1DX Instruction Manual page 87

Case 3: Instantly focus on subjects suddenly entering AF points
Default settings
• Tracking sensitivity:
[Responsive: +1]
• Accel./decel. tracking: [+1]
• AF pt auto switching: [0]
If you want to quickly focus a subject appearing suddenly, setting [Tracking
sensitivity] to [+2] may give better results (p.90).
Case 4: For subjects that accelerate or decelerate quickly
Default settings
• Tracking sensitivity: [0]
• Accel./decel. tracking: [+1]
• AF pt auto switching: [0]
If the subject is in motion, and prone to sudden, dramatic changes in speed,
setting [Accel./decel. tracking] to [+2] may give better results (p.91).
3 Selecting AI Servo AF Characteristics (For a Subject)
Once an AF point starts tracking the
subject, this setting enables the camera
to focus consecutive subjects at different
distances. If a new subject appears in
front of the target subject, the camera will
start focusing the new subject. Also
effective when you want to always focus
on the closest subject.
Geared for tracking moving subjects
prone to sudden, dramatic changes in
speed.
Effective for subjects with sudden
movements, sudden acceleration/
deceleration, or sudden stops.
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