Fixing Exposures with Histograms

While you can often recover poorly exposed photos in your image editor, your best bet is to arrive at the correct exposure in the camera, minimizing the tweaks that you have to make in post-processing. However, you can’t always judge exposure just by viewing the image on your 5D Mark II’s LCD after the shot is made. Nor can you get a 100-percent accurately exposed picture by using the 5D Mark II’s Live View “exposure simulation” feature described in Chapter 6. Ambient light may make the LCD difficult to see, and the brightness level you’ve set can affect the appearance of the playback image.

Instead, you can use a histogram, which is a chart displayed on the EOS 5D Mark II’s LCD that shows the number of tones being captured at each brightness level. You can use the information to provide correction for the next shot you take. The 5D Mark II offers two histogram variations: one that shows overall brightness levels for an image and an alternate version that separates the red, green, and blue channels of your image into separate histograms.