In the preceding lessons, you learned how to apply retouch tools to specific image areas. You used the retouch tools to enhance tonal ranges by darkening or lightening them, and you learned how to use the sponge tool to saturate (or desaturate) the colour in a specific area. These are not the only ways to work with light and colour, however. Photoshop also provides tools for working with colour and brightness that are more global in nature. That is, the changes are applied across the entire image, not just localized areas that you mouse drag over.

In this lesson you will learn about hue, saturation, and brightness. You will learn how to use the Hue/Saturation dialog box, as well as the Brightness/Contrast dialog box. You will also learn how to manipulate shadows and highlights by using the Shadow/Highlight dialog.