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Re: Longitude by Sunrise example
From: Jeremy C
Date: 2010 Feb 5, 14:28 EST
From: Jeremy C
Date: 2010 Feb 5, 14:28 EST
Given the number of sights I did last trip, and this was early on, I can't
remember any details about the sun itself when I observed it. I know from
the date I was in the Phillipine Sea, but beyond that, I don't remember what
else. I will try to note the look of the sun when I shoot them again this
spring.
Jeremy
In a message dated 2/5/2010 2:24:27 P.M. Eastern Standard Time,
marcel.e.tschudin@gmail.com writes:
GRudzinski, you wrote: "The sunset Longitude solution should work out
if a precise table or program is used."
Unfortunately this doesn't depend only of such tools. The atmosphere
doesn't always provide such ideal conditions as in this example. We
know that the refraction near the horizon can be way off the
calculated one and as a result of this also the time of
sunrise/sunset. The observer should verify whether the sun shows at
the horizon some signs of abnormal atmospheric conditions or not. With
the calculation which I have done I wanted to check exactly this, i.e.
whether the observation was done under "normal" condition or not. In
practice the observer doesn't have this possibility. Its himself who
has to judge it from looking at the shape of the rising/setting sun.
Marcel