How can I tell which albums a photo is in?
I'm importing old photos from a negative scanner into Photos for Mac. After importing, I inspect them on the screen of my Mac. Some I then transfer to one or more albums I've created and others I realise I don't need. It isn't easy to remember which of the imports hasn't been added to any album, but I need to identify these so as to delete them. Clearly Photos must tag each photo with quite a bunch of information, including the edits it's had and the albums it's been included in, so theoretically this info is available.
Looking at older questions like this going back to iPhoto, I have not found an answer. Does anyone know how to access this information? I am sure the answer lies in the Photos Library but I don't have the expertise to find it myself.
iMac Line (2012 and Later)