commonlands

Awesome calculator and graphic interface! These calculations appear to use the simplified h=f*tan(Theta) equation. As you've mentioned, this doesn't work for fisheye lenses. I would extend this comment to include any wide-angle lenses with distortion, such as 2.8mm~4mm lenses. If you want to see how distortion impacts camera FoV, you can use another free online calculator: https://commonlands.com/pages/fov-calculator