Photoshop Elements 8 for Windows: The Missing Manual

Scratch Disks

Elements uses a scratch disk—space on your hard drive—when it's busy making your photos gorgeous. The calculations Elements makes behind the scenes are very complex, and it needs someplace to write stuff down while it's figuring out how to change your image. It does so by using a scratch disk if the task at hand is too heavy-duty for your system's main memory to cope with alone.

You probably have just one hard drive in your computer, and Elements automatically uses that drive as the scratch disk. That's fine, and Elements can run very happily without a dedicated scratch disk.

Tip

You can make Elements really happy by keeping your hard drive defragmented and making sure there's plenty of free space available for Elements to use. To defragment in Vista, go to Control Panel → "System and Maintenance" → Administrative Tools → "Defragment your hard drive". In Windows XP, it's Control Panel → "Performance and Maintenance" → "Rearrange items on your hard disk to make programs run faster".

If you're fortunate enough to have a computer with more than one internal drive, you can designate a separate disk as your scratch disk to improve Elements performance. Your scratch disk needs to be as fast as the drive Elements is installed on, or there's no point in setting up a special scratch disk. If you have a USB external drive, for instance, forget it (USB isn't fast enough, even USB 2.0)—just leave your main drive as your scratch disk.

To assign a scratch disk, in the Editor, go to Edit ...