El Capitan - Photos 1.1

Worked exactly as described - note you have to go into Photos to do the actual deletion (it doesn’t delete them for you, just puts them all in a folder for you to delete). My library on here is only around 6000 photos - on a 2015 MBP it scanned and completed in under 10 seconds.

_Chad0_ about Photos Duplicate Cleaner, v1.6.3