This tag starts the definition of how the photo detail pages should be displayed. There may be any number of PhotoDetailPage tags under PhotoAlbumTemplate. When rendering the detail pages photos should be rendered by using PhotoDetailPage definitions in order ... the first photo uses the first PhotoDetailPage definition .. the second uses the next one and so forth until you get to the end at which point you wrap back to the beginning. The current implementation assumes one photo per detail page but we probably want to allow multiple photos per page by allowing multiple image tags on a detail page.