I really want to get a ton of photos off my phone.

I have moved a bunch of them into FOLDERS on my hard drive, but not all.

I know how to compare two directories, but here's what I'm curious about:

If I have one folder, with, say, 1,000 pictures in it (or any file, really) - let's call it "Master". And then I have a dozen folders ("Sub 1", "Sub 2"... "Sub N"), each with 300 pictures in them. How can I sift through and highlight all of the files in Master that are duped in all of the Subs, without having to go folder by folder?

Argh. I can't even figure how to make my question make sense.

You can try software such as dupeGuru.

https://dupeguru.voltaicideas.net/

Thanks. It's been running for a while. This looks like it will do what I ask! Will report back once it's done.I set it up with a subdirectory on my c: drive where I copied all my phone pics, and compared it to the external DIRECTORY where I had EVERYTHING backed up.

It returned a list - a brilliant list - of every DUPLICATE within that external directory (and didn't highlight anything on the c:, and I'm sure there's dupes in tehre).

I need to figure out how to configure it to list everything in that C: subdir that is NOT copied somewhere else.... I am sure it will do it, just gotta PLAY some more.

Took about five hours to scan and build the list.