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    Re: Position from altitude and azimuth.
    From: Antoine Couëtte
    Date: 2020 May 11, 02:19 -0700
    Hello to all,
    Parallax ...
     
    Here, I incorrectly corrected Topocentric Height into Geocentric Height by HP0 (0.1453’) instead of HP (0.0835’) .
     
    I then “artificiallly” increased Geocentric Height by such difference (0.0618’ or 3.7" which still remains within the 6" data accuracy specified here).
     
    Fortunately in this example the extra-parallax effects in both Height and Azimuth due to WGS 84 vs. Spherical Earth are under 0.001’ .
     
    Hence my WGS84 sanity check was immediately able to pick up this undue difference : Azimuth is fine, and we just need to decrease the height by 0.061’ .
     
    Best Navigational Regards to all,
     
    Antoine
       
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