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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Geometry of SNO-T
From: Herbert Prinz
Date: 2004 Oct 14, 13:25 -0400
From: Herbert Prinz
Date: 2004 Oct 14, 13:25 -0400
Alexandre Eremenko wrote: > On Thu, 14 Oct 2004, Herbert Prinz wrote: > > > But let's assume for the sake of argument > > that you have a perpendicularity error > > of 5' that you cannot get rid of. > > How can this be that you cannot get rid of it? > You mean if the adjusting skrew is damaged? This was in the context of a potential impact of non centred mirror surface on sextant performance. I was addressing the hypothetical case where you can't determine perpendicularity error any better on account of the protruding front silvered mirrors. Seas of 4' to 6' will be enough to make the use of cylinders impossible. Then you are limited to the rough method of looking at the arc. The 5' are just a wild guess on the high side. I have never noticed a problem with my Astra. How do your visors work? Can you clamp them on? Herbert Prinz