If I set up a telescope to look inside your window most people would call that an invasion of privacy, even if the telescope was set up on public property. Having a high resolution digital camera where images can be zoomed and a very sensitive microphone that can pick up conversations is similar, in my opinion.
in my neck of the woods if your far enough away that someone has to use binoculars or some other artficial means, even eyeglasses, they are breaking the law. you, the one being observed are not at fault.
