Canon EOS Rebel T1i EOS REBEL T1i/EOS 500D Instruction Manual - Page 94

A AE LockN Use AE lock when the area of focus is to be different from the exposure metering area or when you want to take multiple shots at the same exposure setting. Press the button to lock the exposure, then recompose and take the shot. This is called AE lock. It is effective for backlit subjects. 1 Focus the subject. Press the shutter button halfway. X The exposure setting will be displayed. 2 Press the button. (0) X The icon lights in the viewfinder to indicate that the exposure setting is locked (AE lock). Each time you press the button, it locks the current auto exposure setting. 3 Recompose and take the picture. If you want to maintain the AE lock while taking more shots, hold down the button and press the shutter button to take another shot. AE Lock Effects Metering Mode (p.83) q* wre AF Point Selection Method (p.66) Automatic Selection Manual Selection AE lock is applied at the AF point that achieved focus. AE lock is applied at the selected AF point. AE lock is applied at the center AF point. * When the lens' focus mode switch is set to , AE lock is applied at the center AF point. 94