Just What are Scratch Disks?

Friday, December 08, 2006 Filed in: Adobe

While teaching this week, we got on the topic of how to make Photoshop run faster. Most in the audience thought the answer was to add more RAM (yes that will help), but its not the only way. Adobe Photoshop can recognize up to 3GB of physical RAM, but you can also use virtual memory in the form of a scratch disk.

By targeting hard drive, Photoshop can temporarily use disk space to help in opening large files, ruing complex filters, or performing a resize command. But how do you set this up?

1. Launch your preferences by pressing Cmd + K (Ctrl + K).
2. Find the Plug-Ins & Scratch Disks Category in the drop down menu at the top of the window.
3. Set your first Scratch Disk to a hard drive and click OK.

Internal hard drives are best (as opposed to networked drives). You should also avoid using the Startup (system) drive as this will bog performance down. If you are a video editor, you can target your fast video editing drives. Don't worry, Photoshop will trash any temp files when you quit or on relaunch after a crash.

Be sure to set your Scratch Disk preferences right for a great bump in performance when working with larger files or with several files open.