NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2012 Aug 10, 21:09 -0700
Jim,
Cassens and Plath has a hybrid whole horizon option that is half silvered in the middle and clear on the sides. This should improve early twilight and dim star observations.
http://www.cassens-plath.de/katalog/index.html?startpage=90
Greg Rudzinski
[NavList] Re: Compact Lightweight Metal Sextants - Freiberger Yacht vs. Astra IIIB
From: James N Wilson
Date: 10 Aug 2012 20:25
John:
I agree with many of your sextant comments, except that I have no use for verniers on the micrometer drum. Their ostensible increase in accuracy is questionable, and they introduce the possibility of reading from the wrong end of the vernier, introducing an eleven minute error.
I deplore the idea of eliminating the clear glass on the horizon mirror. I've found it handy with Sun and Moon shots. I also dislike "whole horizon" mirrors, finding the horizon difficult to discern at twilight. Has anyone produced a horizon mirror with a gradation from full on the right to zero on the left? That sounds handy. Should I patent the idea?
Jim Wilson
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