Change the Mission Control Background in Lion [QuickTip]

I don't usually recommend messing about with system files and images, but here's an easy and safe tweak for Lion. You know that grey fabric background of Mission Control? You can change it to whatever you like!

The image file is inside /System/Library/CoreServices/, at /Contents/Resources/defaultdesktop.png. It is 256x256 pixels, and displays in tiled format. This gives the illusion of being one big image, while maintaining a small file size. If you edit this image, you're pretty much limited to colors and textures.

However, if you rename this image to defaultdesktop-old.png, or delete it, the Mission Control background becomes the system standard wallpaper.

The Andromeda Galaxy wallpaper location is /System/Library/CoreServices/DefaultDesktop.jpg. So, in order to make a full Mission Control background replacement, place your custom wallpaper in this location.

     1. Open Finder
     2. Navigate to /System/Library/CoreServices/DefaultDesktop.jpg
     3. Rename file DefaultDesktop-old.jpg
     4. Place any suitable wallpaper .jpg image in /System/Library/CoreServices/
     5. Rename file DefaultDesktop.jpg
     6. Log Out, then Log In

Further theming and tweaks can be done to other images in this folder. You similarly change such items as dashboard background, login screen, dock background, system preferences icons, and more. Be sure to back up before editing any of these files. Post your results in the Customization area of the forum here. Can't wait to see what you come up with!

Update: Just found the location of the Dashboard wallpaper- it's in the same location, but it's a much smaller file called pirelli.jpg. If you rename it in the same way, the default wallpaper is used for the background.

-tonymacx86 & MacMan
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