Nikon 900 - Manual (Page 43)

- 43 - Advanced Settings (M-REC): Metering Method
Autoexposure Lock
When spot metering is used, half-pressing the shutter button
“locks” autoexposure to suit lighting conditions in the center of
the frame. This can be used in combination with focus lock
(see “Focus Settings,” above) to create unusual exposure effects,
such as “washing out” the background while leaving a back-lit
subject at the edge of the frame fully exposed. In the composi-
tion below, the back-lit subject is to one side and the camera is
focused on a point in the background.
To bring out the back-lit subject, aim the camera at the back-lit
portion of the subject and half-press the shutter-release button.
Without releasing the button, return the camera to its original
position and press the shutter button the rest of the way down.
In the photograph that results, exposure will have been adjusted
to capture the back-lit subject while “washing out” the brightly-
lit background.