Auto-exposure lock makes it possible to use spot or center-weighted metering to measure exposure for a subject that will not be in the metering area in the final composition. With the subject positioned in the metering area, press the AE-L/AF-L button to measure exposure. Exposure will be fixed at this setting while the button is pressed, allowing you to maintain the metered value for exposure while recomposing the photograph.
To use auto-exposure lock:
1Press the metering selector lock release (1) and rotate the metering selector (2) to select center-weighted or spot metering. Matrix metering, which measures exposure for the entire frame, will not produce the desired results when used with auto-exposure lock.
2After positioning the subject in the focus area (select the center focus area when using center-weighted metering), press the shutter-release button halfway and confirm that the in-focus indicator (●) appears in the viewfinder (A). Keeping the shutter-release button pressed halfway, press and hold the AE-L/AF-L button
(B).
AB
When spot metering is in effect, the camera measures exposure in the selected focus area (or in the center focus area when a non-CPU lens is in place or closest subject priority is in effect). When center-weighted metering is selected, the camera measures lighting conditions in the entire frame but assigns the greatest weight to an 8-mm circle in the center of the viewfinder.
Exposure will remain locked while the AE-L/AF-L button is pressed. In single- servo or continuous-servo autofocus, both focus and exposure will be locked while the AE-L/AF-L button is pressed. While auto-exposure lock is in effect, an EL indicator will be displayed in the viewfinder.