My roommate and I visited the old prison museum in Deerlodge, MT yesterday and did some half-assed ghost hunting while we were there. We did some bad EVPs and I took photos in many of the locations (as well as doubles of each photo to compare any changes). We didn't catch anything, except for...whatever this is, paranormal or not.
I caught this in one of the cells in the women's ward/maximum security area. We were the only ones in that building in the early afternoon, and I'm 100% certain my roommate was not in frame due to them keeping out of the camera's way. The first photo shows the empty cell with the light coming from a bulb on the ceiling. The second photo, taken in the same moment as the first without me moving or getting another angle, shows some kind of dark blur on the upper left corner. It's very small, so it's not the greatest piece of "evidence" that I wish I could be showing you, but it was the only thing in all of my pictures that looked like this. It's not a finger or hair or anything in front of the camera, since I took multiple pictures of both and concluded they don't look like that at all.
Only other thing we caught was a noticeable temperature drop when my roommate was conducting an EVP in the Hole (solitary confinement), but that's really it, and we don't have proof of that, only our experience.
Sorry if this is either too long or not detailed enough - it's super small and very hard to make out, but I was hoping someone more experienced than me could point me in the right direction of what it is. :) Thanks!

Photo #1 of a room in the old women's ward of the Deerlodge Prison, MT

Photo #2 of the room in the women's ward taken in the same position and same moment as the other one. Weird shape is in upper lefthand corner.
mayhaps your curiosity been fed well by the help of my two colleagues before, yet i am here solely to ease your worry by explaining more details based on my pov. by examining the report with all clipped proofs, most likely it is one of casual paranormal activity. yep, ghosts. moreover, ghost is well-known being attached to certain objects and places where they'd die. in this case: the prison that you guys went to. maybe the ghost belongs to one of their prisoners that died inside. plus ghosts also likes to manipulate surroundings, such as temperatur change which often called thermokinesis, and often display themselves as flickering appearance like the dark blur thingy you've succeeded to captured in the second just make sure you put salt around your house in case the ghost might get attached to you or your room mates. hope this helps you, stay safe!