Empirical Earth · The Boomerangs — Flat-Earth Proofs That Backfire

How your eye works: resolution, perspective & vanishing points

The claim

“Ships, sunsets and skylines vanish from perspective and the eye’s limits, not curvature.”

What is true

Distant things do shrink and blur, and perspective alone accounts for a great deal of what people call curvature.

What is measured

Perspective shrinks things toward eye level, and a sharp eye or a zoom lens can recover anything still in the light. Neither can hide an object bottom-first below eye level. That takes a curve.

What would show this is wrong

perspective or the eye’s resolution limit, not occlusion by a curve, making an object disappear bottom-first while its top stays visible, below the observer’s eye level, over a measured distance.

Sources

  1. Dip of the horizon. The visible horizon lies below true horizontal by θ = arccos(R/(R+h)); about 1° from a 1,000 m hill and ~3° at jet altitude, reduced ~8% by refraction. A standard celesti link
  2. The human eye’s angular resolution. Normal 20/20 vision resolves detail about 1 arcminute across (1/60°), and the diffraction limit for a 3–4 mm pupil is finer still. A telescope’s larger ap link
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