I use "Fast Duplicate File Finder". Highlights duplicates across multiple folders of your choice, or the same folder if the files are the same but have different names.
It will highlight the ones to bulk delete should you wish.
Looking for a "good" software that I can use to remove multiple copies of the same photographs in my picture files. Prefer something that is automatic as I has amassed a lot!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic