Canon POWERSHOT A2400IS User Manual page 104

Q
To conserve battery power when shooting, you can use the optical viewfinder
instead of the screen. Shoot the same way as when using the screen.
Deactivate the screen.
Press the v button to turn the screen off
(p. 43).
(_ The area visible in the optical viewfinder may differ slightly from the
image area in your shots.
_" positions.
Although the camera automatically focuses on subjects, face detection and
focusing is not possible.
42