Did you try Recuva? As to where the space is taken, I use tools like a search for files changed in the last week to find such.
So recently, I've been looking up for some photo recovery softs and tried some out. Everyone of them, in the end, after the scan, turned out to be a soft, which you need an activision key to active it and pay for. But, as I was scanning for deleted photos, it took like 1,5gig from my hdd and I have no idea where it's saved, because they're just some previews or something like that, and they're not saved in the folder of the program, which I tried to recover the files. Maybe you guys have faced a problem like this and maybe you know the answer, where could the previewed pictures could be stored?
P.S. I used Photorec and Stellar photo recovery.
Thanks for the help!