Canon D20 - Manual (Page 114)

Shooting Range and Focusing
114
Shoot after choosing a subject to focus on as follows.
Choose [Tracking AF].
Follow the steps in “Changing the AF Frame
Mode” (p. 112) to choose [Tracking AF].
X is displayed in the center of the screen.
Choose a subject to focus on.
Aim the camera so that is on the desired
subject, and then press the q button.
X When the subject is detected, the camera beeps
and
is displayed. Even if the subject moves,
the camera will continue to track the subject
within a certain range.
X If no subject is detected, is displayed.
To cancel tracking, press the q button again.
Shoot.
Press the shutter button halfway.
changes to a blue , which follows the
subject as the camera continues to adjust the
focus and exposure (Servo AF) (p. 115).
Press the shutter button all the way down to
shoot.
X Even after your shot, is still displayed and
the camera continues to track the subject.
Choosing Subjects to Focus On (Tracking AF)
Still Images