iPhoto 5 or later: Desktop "change picture" feature does not work with new iPhoto albums

In the Desktop & Screen Saver pane of System Preferences, you can select a folder of images or an iPhoto album to display desktop pictures that automatically change at a specified interval, like a slideshow. To enable the feature, just select a source in the pane and then select the "Change picture" checkbox.

While this feature works for iPhoto albums created in iPhoto 4, the "Change picture" checkbox and corresponding pop-up menu become unavailable (dim) when you select an iPhoto album that was created in iPhoto 5 or later. This occurs due to a change in the structure of iPhoto libraries.

As a workaround, you can set your desktop pictures directly in iPhoto instead of in System Preferences:

1. In iPhoto, select the pictures you want to appear on your desktop. Tip: After drag selecting a group of photos, you can Command-click to add or remove photos from the selection.
2. Click the Desktop button in iPhoto. Desktop & Screen Saver preferences will open with the selected photos as an iPhoto Selection, and the "Change picture" checkbox will already be selected.
3. Adjust the time interval or random checkbox as desired.

Note: Sometimes the desktop will "stick" on the previously selected group of images. If this happens, select a background from the Apple Images list in System Preferences, then repeat the steps above. If that still doesn't work, select a background from Apple Images, log out, then repeat the steps above again.

This document will be updated as more information becomes available.