Say you want to straighten a photo of the Empire State Building that looks more like the Leaning Tower of Pisa. You could open the image in Photoshop and go to Image > Rotate Canvas > Arbitrary and then guess at the correct angle. But why go through that when Photoshop can calculate the precise angle of rotation with its Measure tool?

Or maybe you photographed an artist's print at an angle, and now you need a straight-on shot of the work. Don't go back to the gallery -- Photoshop's Crop Tool has a Perspective feature that will complete the transformation for you (Figure 1).

Figure 1. You can crop and correct perspective at the same time.

These videos are QuickTime movies. You can download the files by option- or right-clicking on the links and saving the ".mov" file to your hard disk. Or you can simply click the following links to play them:

1. Straightening Crooked Images (7.8 MB)

2. Cropping and Straightening Photos Automatically (4 MB)

3. Correcting Perspective with the Crop Tool (7.6 MB)

If you do not have QuickTime installed, you can get it here:

Excerpted from "Photoshop CS2 Essential Training" © lynda.com. ALL RIGHTS RESERVED.