Using The Viewfinder - Canon Digital IXUS 850 IS Troubleshooting Manual

Histogram Function
The histogram is a graph that allows you to check the brightness
of the image. The greater the bias toward the left in the graph, the
darker the image. The greater the bias toward the right, the
brighter the image.
If the image is too dark, adjust the exposure compensation to a
positive value. Similarly, adjust the exposure compensation to a
negative value if the image is too bright (p. 52).
Sample Histograms

Using the Viewfinder

The viewfinder can be used to conserve power by turning the LCD
monitor off (p. 12) while shooting.
18
Dark Image Balanced Image Bright Image