When I was in my last house, I had a pretty bad issue with my neighbor that ended up going to court. I put a camera in my back yard that pointed at his back yard. The pole had two industrial sirens on it and when he decided to party all day with the radio on high, I would turn on the sirens. Needless to say, him and his guests couldn't stand in the back yard because the sound was so loud. He called code enforcement on me about the camera being installed with out a permit. A few days later the enforcement officer told me and my neighbor that I had to take the camera down. If I was to pull a permit for a security camera installation, I could have all the cameras that wanted pointing right into his yard and the neighbor would have to live with it. I'll post some pics if I can find them.
Moral to the story, make good with your neighbors and ask them if they mind. This problem cost me a fortune in attorney's fees. The neighbor had an injuction placed on him stating that he would be fined or arrested if he broke the county noise statue. We ended up moving shortly after.