When you import photos, you can choose to download to your computer full-resolution copies of the master photos (default) or low-resolution copies, called preview files. Preview files appear in your catalog as space-saving copies of the high-resolution originals. When you perform an operation that requires the original photo, you are asked to insert the disc containing the offline photo. You can then decide whether to use the preview file or bring in a full-resolution copy of the photo.

If you choose to use preview files, you need to assign an Offline Volume Name to the CD or DVD containing the master files. Make sure to write the Offline Volume Name on the CD or DVD, so that when Photoshop Elements requests the master disc (it provides the reference name for you), you can insert the correct disc.