In many cases, e.g. when splitting up a library, you’ll find yourself wanting to move an album full of photos to another library instead of copying them. What this effectively means is first copying the photos to the new library, then deleting the photos from the old library. Unfortunately, Photos does not provide a way for third party apps such as PowerPhotos to delete photos from a library, so there is no way for PowerPhotos to implement a “move” feature in this manner.
This being the case, the best way available to perform a move is to copy the album using PowerPhotos, then go back and manually delete the photos from the original library. This is slightly tricky, since when you select photos in an album and press the “delete” key, it does not delete the photos from your library as a whole, it only removes them from the album. Deleting the album itself just deletes the album itself, and leaves the photos in your library. The trick is to select all the photos and hit command-delete, instead of just delete by itself. This will remove the photos from both the library and the album.
To entirely remove an album of photos from a library:
- Open the library in Photos (not in PowerPhotos)
- Select View > Albums from the menu bar up top to see your albums
- Double click the album you just copied, to show all the photos contained in the album
- Press command-A to select all the photos in the album.
- Press command-delete to remove the photos from both the album and the library.
- Click the back button in the upper left to return to your album list.
- Control-click on the album and select “Delete album” to delete the now empty album.