Wanna see for yourself that the earth isn't flat? You can fly a Russian MiG-29 to 60,000 feet, and roll the aircraft to see that the earth is a globe. No fisheye. Simply pure, clear, canopy plastic. Where can you fly the MiG-29? In Russia, of course. But you can watch a flight here:

MiG-29 High Altitude Stratosphere Flight - long version 8 camera HD | flight data

https://www.youtube.com/watch?v=PEH8iLjlodM