There's a problem that's been nagging me since Apple got rid of Aperture and iPhoto and merged them into the mess that is Photos:  how do I find photos that are not in an album?  A photo can be added to more than one album, but once added, the photo continues to show up in the "All Photos" section.  It's obvious it should work this way.  After all, the section is called "All Photos".  The problem is I don't work that way.  I like to organize my photos into Albums, but I don't always do it right away. How do I tell which photos still need to be organized?

It turns out there is an easy way to do this provided you do it on a Mac and not an iPhone or iPad.  Create a Smart Album, and include all photos whose "Album" "is not" "Any".  I call this album "Camera Roll":

Once created, this album will show all photos that are not in an album on their own. Apple:  please synchronize these smart folders to iOS devices.