Nikon D5100 Reference Manual page 5

[] The [] Button
Exposure compensation can also be
set by pressing the [] button and
rotating the command dial. The
selected value is shown in the
viewfinder and information display.
[] button Command dial
-0.3 EV +2 EV
[] Mode M
In mode M, exposure compensation affects only the exposure indicator; shutter speed and
aperture do not change.
[] Using a Flash
When a flash is used, exposure compensation affects both background exposure and flash
level.
[] See Also
For information on choosing the size of the increments available for exposure
compensation, see Custom Setting bl (EM steps for exposure cntrl., _ 159). For
information on automatically varying exposure over a series of shots, see page 88.
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