You can clearly see a windmill being restored height of camera: 1.5 feet above sea level, distance Horizon should be viewable 1.5 Miles using this basic calculator:
http://www.ringbell.co.uk/info/hdist.htm however in this video using a camera's optical zoom we can actually see at least 6 times farther then we should be able to on a convex (ball) Earth.
Simple Geometry if Earth is:
Concave: 1 part Sky 1 part Earth.
Flat: 2 parts Sky, 1 part Earth.
Convex: 3 parts Sky 1 part Earth.
" class="bbc_link" target="_blank" rel="noopener noreferrer">Note: This image my base as calculated was wrong, this guy is only about 5.5 feet off the ground (but 1.5 feet above sea level) and the starting milage is about 1.5 miles to get 1.5, 3, 6, 10 miles in that order but still the point remains even though the base guess was off by about 1.1 feet. Edit: Further examination of this shows the guy was actually standing around 5.5 feet above sea level (slight camera hunch on tripod maybe? With sea level rising at least 4 feet in the distance which gives you 1.5 feet above sea level) Edit: Also the 1x, 4x ect is optical zoom level.

Still not convinced that we live inside the Earth? Well look at this when it's perfectly level (as you can easily see by the fishhead camera not showing a curve you can see almost exactly 1 part Earth to 1 part Sky: Skip ahead to 1:50-1:60 to see this demonstrated)
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