
Quoting
BOR
The fact he took pictures of it means it is "open and obvious" to any invitee/passerby/trespasser. As Panther points out, as long as it is not focused mainly on a personal area, such as a bedroom window, but a common area, you are fine.
He has no grounds to sue. If he does hire a lawyer to defend you and countersue for Abuse of Process.
AOP is where a person sues you, with no recognizable Cause of Action, just to harass/intimidate you.
Similar to SLAPP suits; Strategic lawsuits against public participation.
You bad mouth my company, I shut you up with the threat of a lawsuit, time, money etc.