At first I thought this might be very gimmicky, like many of the OS X window manager tweaks that are out there in the wild. This one I however found very useful. I’ll state up front that if you don’t often use quicklook, then feel free to ignore the rest of this article.

So what does X-ray mode do for Quick Look?

Instead of just seeing the regular folder icon in Quick Look, the folder icon will be semi-transparent, with previews of the folder’s contents visible in the Quick Look window. What’s more, the preview images will rotate automatically, moving through each item in the folder.

Desktop Bin.png

You can enable X-ray mode for Quick Look in a couple of ways, but the quickest and simplest way to do it is to simply turn on X-ray mode with a simple Terminal hack.

Fire up Terminal (/Applications/Utilities/Terminal.app) and paste the following:

defaults write com.apple.finder QLEnableXRayFolders 1

Hit Return, then Alt+right-click on the Finder icon in your Dock and click on Relaunch. X-ray mode should now be enabled. Hit the spacebar when you’ve selected any folder in Finder to test it.