Photoshop CC: The Missing Manual, 2nd Edition

Using Levels

The adjustments you’ve seen so far are okay when you’re just starting out with Photoshop, and they’re darn handy when you’re pressed for time. But sooner or later you’ll encounter images that can only be whipped into shape by more powerful tools, such as Levels and Curves. (Though these days you could simply use Camera Raw to fix all your images, which is much easier. After all, it’s available as a filter inside Photoshop, as the box on Using the Camera Raw Filter explains.)

With a single Levels adjustment, you can fix lighting problems, increase contrast, and—in some cases—balance the color in your image. (If you’ve got major color problems, you need to use Curves instead; skip ahead to Working with Curves to learn how.) Levels adjustments change the intensity levels (hence the tool’s name) of shadows, midtones, and highlights, and are a very visual and intuitive way to improve images. And because they’re available as adjustment layers (yay!), they’re nondestructive and won’t harm your original image; plus they come with an automatic layer mask.

In this section, you’ll learn how to use Levels adjustments in a few different ways so you can pick the one you like best. But first, you need to get up close and personal with the mighty histogram, your secret decoder ring for interpreting the info in your photos.

Histograms: Mountains of Information

A histogram (Figure 9-13) is a visual representation—a collection of tiny bar graphs, to be precise—of the info contained in an ...