Master Quick Look’s Full-Screen Feature

Quick Look lets you select a file and, by hitting Space, quickly preview its contents without having to open it in any application. Like many apps on your Mac, it has a full-screen mode, which can be useful when examining things like images. There are quite a few methods of switching to full-screen mode, as follows:

• If you haven’t yet activated Quick Look for the file, select it and hit Option+Space instead of just Space, which is the usual Quick Look shortcut key. This will instantly open Quick Look in full-screen mode. A drawback of activating Quick Look in this mode is that hitting Option+Space again won’t close the Quick Look window. Instead, you must hit Esc or click the close button on the Quick Look floating toolbar.

• If already viewing a file in Quick Look and your Mac has a trackpad, you can switch to full-screen mode using the pinch-to-expand gesture (that is, placing your finger and thumb together on the trackpad and moving them apart; contracting them again will revert to a standard window). However, regardless of whether you have a trackpad, you can also switch to full-screen mode in an open QuickTime window by clicking the arrow at the top right of the window.

• There’s also a secret setting that lets you switch to full-screen mode (and back) in Quick Look when you’re viewing a file by rolling up the scroll wheel on a mouse or scrolling up on a trackpad. Scrolling down restores the Quick Look window to normal size.

Although seemingly useful, bear in mind that this tweak will mean you will no longer be able to scroll in any documents you Quick Look, unless you click and drag the scrollbar scroller at the right edge.

To make the change, open a Terminal window (open Finder, select the Applications list, and then in the list of applications double-click Terminal within the Utilities folder), and type the following: 

defaults write com.apple.finder QLPreviewFakeMagnifyWithScrollwheel -bool TRUE;killall Finder

The change will take effect immediately, so give it a try.

To deactivate the feature, open a Terminal window, and type the following:

defaults delete com.apple.finder QLPreviewFakeMagnifyWithScrollwheel;killall Finder

Note that if you’re Quick Looking an image smaller than your monitor’s reso- lution in Quick Look’s full-screen mode, it will be automatically magnified to fill the space. You can temporarily view the image at 100 percent by holding down the Option key.