NavList:

Dear All,

As this specific topic also requires a dedicated thread, in the end-remark #2 of this most recent post, I indicated that I do not actually know where and how it is possible to compute refraction between 2 points on Earth known by their respective 3D Coordinates on WGS84.

For example from the Photographer's computed position (WGS84 coordinates assumed to be at 45°08.510701'N 007°52.153984'E 381m) to MonViso (WGS84 coordinates assumed to be at 44°40.059'N 007°05.434'E 3793m) I have computed distance and elevation at 80.776136 km and 2°11.01' .

For this awesome Moon-MonViso-Superga picture, I "observed and measured" a refraction of 5.66' for MonViso seen at a local height of 2°16.67' from the Photographer's computed position heer-above.

But I do not know of any practicable method of reliably checking that this 5.66' refraction value is reasonably realistic given what we know of the way light rays are refracted between 2 points at finite distances within the Earth Atmosphere.

Any NavList Member to bring light on this topic ?

Thanks in advance.

Kermit