Canon EOS M200 Advanced User Guide - Page 191

Exposure Lock (AE Lock) M You can lock the exposure when you want to set the focus and exposure separately or when you are to take multiple shots at the same exposure setting. Press the button to lock the exposure, then recompose and take the picture. It is effective for shooting backlit subjects, etc. 1Focus on the subject. zz Press the shutter button halfway. 2Press the button. zz A [A] icon is displayed in the lower left of the screen to indicate that exposure is locked (AE lock). zz To cancel AE Lock, press the button again. 3Recompose and take the picture. AE Lock Effects Metering Mode q wre AF Point Selection Method Automatic Selection Manual Selection Exposure centered on the AF point Exposure centered on the selected in focus is locked. AF point is locked. Exposure at the center of the screen is locked. * When set to [q] with [z: Focus mode] set to [MF], exposure at the center of the screen is locked. zzAE lock is not available in bulb exposure. 191