In some ways, working with raw photos in iPhoto is no different than working with JPEG photos. You can import raw photos into your library, edit them using all of the edit-view features I’ve described previously, and share them using all of iPhoto’s sharing features.
Importing raw photos. Aside from making sure you have plenty of free disk space, you don’t have to do anything special to import raw photos into iPhoto. If iPhoto supports your camera’s raw format, it imports the raw photos and stores them in your photo library.
JPEG companions. When you import raw photos, iPhoto creates JPEG versions of them. You don’t see thumbnails for these JPEG companions in your photo library, but they’re there.