It would also be rude to ogle a well-covered woman (and plenty of people do exactly that) and stare her up and down. What is she supposed to do in that situation when she can't cover up any more? Stay home if such ogling bothers her?

Anyway, if some guy was taking pictures secretly of my daughter, for instance, I would kick his ass, regardless of the legality of him doing so. If a co-worker was secretly taking pictures of another co-worker, especially of body parts, I would consider that to be non-preofessinal conduct and work to have that toxic presence removed from work.