Nikon D300s - Manual (Page 144)

118
Z
Exposure Compensation
Exposure compensation is used to alter exposure from the value
suggested by the camera, making pictures brighter or darker.
In exposure mode h, only the exposure information shown in the
exposure indicator is affected; shutter speed and aperture do not
change.
To choose a value for exposure compensation, press the E button
and rotate the main command dial until the desired value is
displayed in the control panel or viewfinder.
E button
Main command dial
±0 EV
( E button pressed)
–0.3 EV +2.0 EV