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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Comparison, Pan of Oil vs Mirror Artificial Horizon
From: Fred Hebard
Date: 2015 Jun 22, 17:21 -0700
From: Fred Hebard
Date: 2015 Jun 22, 17:21 -0700
Measuring the semi-diameter of the sun by first touching the top and bottom limbs is more accurate.
For the method, see, for instance, Elementary Treatise on Nautical Astronomy: For the Use of Science Classes ...
Fred Hebard
mbiew---.net
I check the index error by aiming at the sun and making the two images coincident. I just checked it again and still get 6' to 6.5' off arc. So I would add the 6' onto my Hs. The sextant is a brand new Ogawa Seiki made in 1984, looks very much like the Tamayas.