In case it helps someone else. I had a HikVision DS-2CD2332-I EXIR Turret camera that had a nasty IR glare at night. There was a drain pipe close by and a light fixture plus guttering just above. I just knew one of these had to creating the glare thinking that since the IR and camera lense on the EXIR turret aren't behind the same glass like a dome camera. Well, I was wrong. After all kinds of contortions trying to hang paper up to block each suspected source just on a chance I grabbed my eye glass cleaning cloth and cleaned both lenses. Problem solved.
