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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Benefits of Stigmatizing
From: Jeremy C
Date: 2010 Sep 22, 14:06 EDT
From: Jeremy C
Date: 2010 Sep 22, 14:06 EDT
I think you are right George, it is called an astigmatiser, there doesn't
seem much information on the web about them. I am many hours from my
library so can't check my 1984 Bowditch which probably at least mentions
them.
I believe that the star as a line is thought to be easier to super-impose
on the horizon. I remember my instructors mentioning it in school but they
certainly weren't sold on it's use in practice. I am sure that if they
were worth the effort and cost, I'd have seen one at least once in my
career.
The double prism doesn't help with a poor horizon in my experience (if it
is the same device). I don't use the horizon to determine whether the
sextant is perpendicular so I don't see how that device would be helpful.
Jeremy
