Exactly. You can go into a museum, take a photo, and do with it whatever you want, legally, even though the museum usually claims that you need their permission

Exactly. You can go into a museum, take a photo, and do with it whatever you want, legally, even though the museum usually claims that you need their permission to publish it. The problem is of course that you can't take photos of stuff that isn't exhibited, so you need to get their permission to check out the stuff in the basement.