Canon EOS 90D Advanced User's Manual page 143

Subject eyes may not be detected correctly, depending on the subject and
o
shooting conditions.
To disable Eye Detection AF without using menu operations, press these
o
buttons, one after another: < G >, and < B >. To resume Eye Detection AF,
press the < B > button again.
Setting the Initial Servo AF Position
You can freely set the initial position for Servo AF when [ 8 C.Fn II-11:
Initial Servo AF pt,
(1)
Selecting the AF Method (Live View Shooting)
/ c ] is [1:Initial AF pt set for
1
Set the AF method to [u+Tracking]
(=137).
2
Set the AF operation to [Servo AF]
(=124).
3
Set the AF point (=132).
Use < j > < 9 > or tap the screen to

move the AF point (1), then set it.
Pressing < j > or the < 0 > or < L >

button will return the AF point to the
screen center.
/ c ] ( = 566).
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