Did you know that you can use the Crop tool to resize the canvas in Photoshop CS6?
In addition to Cropping images, and performing a Perspective Crop, you can also resize the image canvas using the new and improved Crop tools in Photoshop CS6.
Resizing the image canvas is probably one of the most frequent tasks you do in Photoshop. It’s fairly easy too, and works in all versions of Photoshop. Choose Image > Canvas Size ( or press Alt+Ctrl+C) and enter the new values.
Photoshop CS6 introduces one more method. And a fairly cool one, I think.
1. Choose the Crop tool. The Crop handles appear on the edges of the picture.
2. Drag the handles outwards to resize the canvas. (Press Alt/Option to resize from the center)
3. Press Enter (Windows) or Return (Mac OS) to commit the changes.