In Photoshop CS4, Adobe introduced a new feature: the Canvas Rotation Via Trackpad plug-in. This was designed to help trackpad users rotate the canvas view more easily, without actually editing the image. You can bring the tool up via the trackpad using a multitouch gesture; when you do this, a large compass rose icon will appear on your screen and you can adjust the rotation of your canvas view.
In all versions of Photoshop, the canvas is your workspace -- the area of the screen in which you'll modify images or create new images from scratch. You can resize and reorient the canvas to suit your personal preferences and the particular image you're working on. You can open as many canvases at one time as you need to.
Trackpads and Touch Screens
You can interact with your computer in many ways. For desktops, a mouse is typical; if you're a graphics designer you may prefer to use a tablet instead. For laptops, a trackpad is a common interface. You run your finger over the trackpad to move the mouse pointer. Tapping the pad can act like clicking the mouse. Some trackpads are capable of processing input from more than one touch at a time. Another interface is a touch-sensitive screen, which allows a more hands-on approach to editing images.
Multitouch gestures use trackpads and touch-sensitive screens in a sophisticated way. By touching the trackpad in more than one place and moving your fingers in particular ways, you can give the computer a broader range of commands than simply pointing and clicking. Multitouch gesture capability turns the trackpad into a much more versatile interface; however, some people find that they trigger multitouch functionality by accident when they don't want to.
The Rotate Canvas View Tool
The Rotate Canvas View tool is nondestructive -- it doesn't have any effect on the actual document you're working on, but just changes the way it's displayed. You can bring up the Rotate Canvas View tool either by selecting it from the menu or by placing two fingers (or thumb and forefinger) on the trackpad or touch screen and making a circular gesture. This will bring up a compass rose, indicating the orientation of your image. To reset the view back to normal, click Reset View in the Options bar.
Disabling Canvas Rotation Via Trackpad
Some users have found that they accidentally perform the multitouch gesture for canvas rotation and thus bring the tool up by mistake. This can be irritating and intrusive. You can download a plug-in from Adobe that disables Canvas Rotation Via Trackpad.
- Adobe Photoshop: CS4 Help: Use the Rotate View Tool
- Adobe Photoshop: For Macintosh: Adobe Photoshop CS4 Disable Canvas Rotation Via Trackpad Plug-In
- "Photoshop Elements 9 for Mac OS X: Visual QuickStart Guide"; Jeff Carlson; 2010