Your camera’s histogram can be useful in figuring out exposure, but you can also use the histogram to determine the in-camera setting for TONE (contrast). The histogram is a visual reference to tonal range. If the bell of the graph is quite narrow, it is indication a lack of contrast in the scene. To increase the level of contrast in the picture, increase the level of TONE compensation in the shooting menu. Similarly, if the contrast range is too great, you can reduce TONE compensation.
Adapted from Digital Wildlife Photography by Chris Weston (Photographers’ Institute Press, 2008; $20)