This being said there would be a significant margin of error associated with angle measurements due to boat tilt. So the location of the object is only a rough approximation but an approximation could be good enough. Also, kind of obvious, but a camera would only really work during the day.
The hardest part of this process would be to actually locate an object of interest if there is one in the image. So I'm kinda looking at this; not much progress yet, so help is really welcome.
Also, cameras are the only thing I've looked at so far. Other inputs such as radar could likely work much better so we can't really restrict ourselves just to cameras.
Thanks for reading,