Adobe Photoshop Elements 3.0: A Visual Introduction to Digital Imaging

The Brightness/Contrast feature that we looked at in the last chapter is a great way to start to change the tones in your images, but as your skill and confidence increase you might find that you want a little more control. Adobe included the Histogram feature and the Levels function from Photoshop in Elements for precisely this reason.
Version 1.0/ 2.0: Image > Histogram
The first step in taking charge of your pixels is to become aware of where they are situated in your image and how they are distributed between black and white points. The Histogram palette displays a graph of all the pixels in your image. The left-hand side represents the black values, the right the white end of the spectrum. As we already know, in a 24-bit image there are a total of 256 levels of tone possible from black to white each of these values is represented on the graph. The number of pixels in the image with a particular brightness or tone value is displayed on the graph by height. See Figure 5.7.
After a little time viewing the histograms of your images, you will begin to see a pattern in the way that certain styles of...