Compose photographs with off-center subjects.
Focus: Position the subject in the focus frame and press the shutter button halfway to lock focus and exposure. Focus and exposure will remain locked while the shutter button is pressed halfway (AF/AE lock).
Recompose: Keep the shutter button pressed halfway.
Shoot: Press the button all the way down.
If [AE-LOCK], [AF-LOCK], or [AE/AF LOCK] is assigned to the [Fn] button, the focus and/or exposure will lock while the [Fn] button is pressed and remain locked even when the shutter button is pressed halfway.