Taking a pic of the pic as if I am looking at it through a window we can calculate the numbers on a flight at 30,000 feet. In just less than 10 miles it will go off the top of the camera, where the cross hairs are in the center would be about 21 miles away, and just more than half of that more, where 60 crosses the line, would be about 45 miles. ALL figures alter with variable elevation. I think most people can see planes and contrails after 8 degrees on a normal day, some areas maybe 6, but they are getting pretty small to see. The average cell phone appears to have a 50 degree view.