One-Click Desktop Backdrop
iPhoto’s desktop-image feature is the best way to drive home the point that photos of your children (or dog, or mother, or self) are the most beautiful in the world. You pick one spectacular shot to replace the standard Mac OS X swirling blue desktop pattern. It’s like refrigerator art on steroids.
Creating wallpaper in iPhoto is so easy that you could change the picture every day—and you may well want to. In iPhoto, click a thumbnail and then click the Desktop button on the bottom panel (or choose Share → Desktop). Even though the iPhoto window is probably filling your screen, the change happens instantly behind it. Your desktop is now filled with the picture you chose.
If you choose several thumbnails or even an album, iPhoto assumes that you intend to make Mac OS X rotate among your selected photos, displaying a new one every few minutes on your desktop throughout the day. To confirm its understanding, Mac OS X opens up the relevant panel of System Preferences, so that you can click the Desktop tab and specify how often you want the photos to change.
Just three words of advice. First, choose a picture that’s at least as big as your screen (1024 x 768 pixels, for example). Otherwise, Mac OS X will stretch it to fit, distorting the photo in the process. (If you’re really fussy, you can even crop the photo first to the exact measurements of the screen; in fact, the first command in iPhoto’s Constrain pop-up menu [page 150] lists the exact dimensions of ...