"ask any body who has been sexually assaulted if they'd rather had had a photo taken"
Tell you what, why don't I ask my sister how she felt when some slimy pervert stuck his phone up her skirt and took a photo? Oh, wait, I don't have to - I already know that she was shocked and upset by it. I also know that had I been there, said pervert would have eaten his phone without salt.
You are speaking from a position of ignorance, Chris. Taking an upskirt photo without permission may not be on the same level as groping a woman or pulling off her clothes, and it's certainly nowhere near actual rape, but it's still a violation.