1.16. Using the Exposure Histogram at Night

A histogram is a bar graph showing a distribution of values. An exposure histogram shows the distribution of lights and darks in an exposure. (See examples of exposure histograms on pages 60-61, or check out how they look in your camera.)

Your camera will show the exposure histogram for a capture you've made. Some cameras will show the histogram during composition before you've actually made the exposure. Check your camera manual for details on how to display exposure histograms.