Sony NEX-7 - Manual (Page 28)

GB
28
Locking the AE with AEL button
1 Set the AF/MF/AEL switch
lever to AEL.
The button becomes the AEL (AE
lock) button.
2 Focus on the spot for which you want to set the exposure.
3 Press the AEL button.
The exposure is locked and (AE lock) lights up.
4 Holding the AEL button down, focus on your desired
subject and shoot.
You can keep the AE locked until you press the AEL button again by
selecting MENU
t [Setup] t [AEL].