NavList:

I happened to shoot Sun's backsights only twice, when on both occasions the horizon was obscured in the direction of the Sun because of a remote thunderstorm with very heavy rain ...

I had to draw a figure to deal with the height correction for this specific observation. If I remember well - and somebody will help me here, if I am in error, Thanks - I first had to perform the DIP correction, then take the supplement to 180° (i.e. consider that a 100° back sight would be the same as a 80° direct sightg), then at last consider an apparent UL backsight as a LL direct sight (or consider apparent LL backsight as a UL direct sight). And if I remerber well also (some 35 years ago), when I was swinging my sextant, the apparent Sun arc had its center inverted, i.e. if I shot a backward apparent UL, then the Sun would always stay below the horizon during the swing. Could somebody confirm to-day (Any reader near the Equator ?) ? If I attempt doing it again from here I would have to observe a high altitude star backwards (NOT an easy task at all, as I would guess).

Best Regards

Antoine M. "Kermit" Couëtte
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