–@SallyHogshead via Twitter
want to save your sanity and forgo deleting files manually for a much
easier option like Duplicate Annihilator.
This is a software program that does the work for you by automatically
tagging repetitive files using a fancy algorithm. You can then either
choose to rename the image and move it elsewhere, or (more likely) delete altogether.
The $7.95 price is a small price to pay for saving yourself a lot of aggravation and possibly hours of work.
($30) that offer similar functionality, but Duplicate Annihilator seems
to be the go-to choice with a lot of happy users. -Jeana