Reference Manual (complete instructions)

115P, S, A, and M Modes
Exposure Compensation
Exposure compensation is used to alter exposure from the value
suggested by the camera, making pictures brighter or darker
(0 297). In general, positive values make the subject brighter
while negative values make it darker. It is most effective when
used with M (Center-weighted metering) or N (Spot
metering) (0 111).
–1 EV No exposure
compensation
+1 EV