>>109014306To narrow down single individuals using a given file, try restricting or establishing a filename to look for- any different filenames from what you're looking for there are likely to be different people, but if you can find multiple instances of a single file being used with a single filename across a long period of time you're closer to establishing a single person's presence, that is, unless a given file they use has a filename other people also like to use.
I think there are also some other methods that can be used with images to establish whether or not an image is being used by/is from a single given specific individual, but I can't remember what it is, I think it's something to do with the code inherently embedded in an image but I can't remember what it's called or how to access and check it. It's very interesting that sometimes, even without trips or names, it's possible to recognize and identify behaviors across different boards.