Nikon D300 User Manual page 78

cl: Shutter-Release Button AE-L
At the default setting of [Off], exposure only locks when the AE-L/
AF-Lbutton is pressed. If [On] is selected, exposure will also lock
when the shutter-release button is pressed halfway.
c2: Auto Meter-off Delay
This option controls how long the camera
continues to meter exposure when no
operations are performed. Choose from 4 s,
6 s, 8 s, 16 s, 30 s, 1 minute, 5 minutes,
10 minutes, 30 minutes, or until the camera is
turned off ([No limit]). The shutter-speed and
aperture displays in the control panel and
viewfinder turn off automatically when the
exposure meters turn off.
Option
_4s 4 s
_6s 6s(default)
_8s 8 s
_16s 16s
_:_s 30 s
_lm 1 min.
_5m 5 min.
_10m10 min.
_30m30 min.
W°o No limit
Choose a shorter meter-off delay for longer battery life. When the
camera is powered by an optional EH-Sa or EH-5 AC adapter, the
auto meter-off delay is equivalent to [No limit].
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