NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Compact Lightweight Metal Sextants - Freiberger Yacht vs. Astra IIIB
From: Alexandre Eremenko
Date: 2012 Aug 11, 04:18 -0400
From: Alexandre Eremenko
Date: 2012 Aug 11, 04:18 -0400
Dear Jim and John, > I deplore the idea of eliminating the clear glass on the horizon mirror. > I also dislike "whole > horizon" mirrors, finding the horizon difficult to discern at twilight. I completely agree. Classical large, 1/2-silvered mirror is the best solution. > 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? I don't think this is a good idea. But you can try to patent it:-) John, you say: > The only sextant that does the optics right is the Navy Mark > II, it has a very wide, high quality, FOV. I would be more cautious and say: "The only sextant I tried..." Have you ever tried an SNO with an inverting scope? (Of those I tried it has no equal...) But on a small boat, in rough sea, I think the only reasonable solution iz a "zero-tube". Alex.