Canon EOS 90D Advanced User's Manual page 125

One-Shot AF for Still Subjects
This AF operation is suited for still subjects. When you press the shutter
button halfway, the camera will focus only once.
In viewfi nder shooting, once the subject is in focus, that AF point is

displayed, the focus indicator < o > in the viewfi nder lights up, and the
camera beeps.
In Live View shooting, once the subject is in focus, that AF point turns

green and the camera beeps.
The focus remains locked while you hold down the shutter button halfway,

allowing you to recompose the image before taking the picture.
If [ 5 : Beep] is set to [Disable], the beeper will not sound when focus is
o
achieved.
AI Servo AF ( Viewfi nder Shooting) or Servo AF (Live View
Shooting) 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.
In viewfi nder shooting, once the subject is in focus, that AF point is

displayed.
In Live View shooting, once the subject is in focus, the AF point turns

blue.
The exposure is set at the moment the picture is taken.

The beeper will not sound even when focus is achieved.
o
The focus indicator < o > in the viewfi nder will not light up.
o
Selecting the AF Operation
125