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AH: windproof shades material
From: Igor S.
Date: 2021 Mar 17, 09:38 -0700
From: Igor S.
Date: 2021 Mar 17, 09:38 -0700
In the book Basics of Nautical Astronomy by N. N. Matusevich (1956) has mentioned the recommended material for the shades of artificial horizon, namely Mica (see for details: https://en.wikipedia.org/wiki/Mica). Due to its crystal structure it won't deflect sun rays contrary to normal glass.
Has someone compared sun sights with and without using shades? Is there any difference ?
Are the two pieces of normal float glass 2 - 4mm at an angle of 90 degree enough to get accurate results at any sun altitude?
kind regards,
Igor
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