Tracking Sensitivity
A setting that controls how quickly continuous autofocus abandons its current subject when something else enters the frame.
Measured in
scale (−3 to +3 typically)
In depth
A low, sticky setting ignores obstructions and holds the original subject — right for a football match where players cross in front. A high, responsive setting switches immediately — right for birds in flight appearing suddenly at a new distance. Getting it wrong is the most common cause of a technically capable camera missing focus repeatedly.
Examples in practice
Set to its stickiest value, autofocus stays on a runner even as an official walks between them and the camera.