If you aren't moving your position and you have a topographic map of your territory, and you have a line-of-sight weapon that doesn't need wind or range adjustments... then you don't really need to know where your target is in 3 coordinates, you only need 2.

I would expect that ambient lighting changes are harder to compensate for when selecting targets.

It is, however, terribly irresponsible to do this, since temporary reflectors like water puddles or a misplaced water glass can be inadvertently weaponized.

For small areas, an overhead water sprinkler would be much, much safer and not need aiming at all.

Yeah, I agree - this was an unsafe system. We lived in a secluded space, and that surely helped prevent accidents, but i'd not set it up like this again even if I lived alone.

As others suggested, a water cannon would be safer (not entirely sure about a sprinkler - in my experience with pidgeons they do seem able to get used to all but most unpleasant defences). Also, an auto-firing high pressure, precise water cannon would be a cool side project :->

That was done on the cheap; there is a finite number of spots the pidgeons used to occupy. Pigeons also have a relatively fixed height when stationary. The camera was in a fixed position. I mapped the area the camera was observing manually: railing, base of the terrace, etc. I was contemplating using two cameras but the cheap setup worked nearly flawlessly when it comes to triangulation.