NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: sun sights
From: Patrick Goold
Date: 2011 Jan 31, 12:05 -0500
From: Patrick Goold
Date: 2011 Jan 31, 12:05 -0500
Fred, Hewitt, Gary,
Thanks for your comments! They are very helpful. I am encouraged to think that I am getting the hang of this but also chastened that I need to be more careful.
I am embarrassed by the inexplicable subtraction error that Gary caught. When corrected, the result is an intercept very near the one given by the on-line calculator.
Treating the first sight as an upper limb instead of a lower brings that value right into line with the others. I can't imagine how I would have made that mistake. Given the combination of filters I use on the sextant itself and on the artificial horizon, the image reflected by the AH and the image reflected from the index mirror are different colors. Orange over green for a lower limb. Could I really have inverted that without noticing? But there is no denying the observation looks much, much better on the assumption that that is what happened.
Jeremy, I will try spreading out my shots. I am using an artifical horizon, though. That limits how low one can observe.
Thank you all again for your help.
Best regards,
Patrick
Thanks for your comments! They are very helpful. I am encouraged to think that I am getting the hang of this but also chastened that I need to be more careful.
I am embarrassed by the inexplicable subtraction error that Gary caught. When corrected, the result is an intercept very near the one given by the on-line calculator.
Treating the first sight as an upper limb instead of a lower brings that value right into line with the others. I can't imagine how I would have made that mistake. Given the combination of filters I use on the sextant itself and on the artificial horizon, the image reflected by the AH and the image reflected from the index mirror are different colors. Orange over green for a lower limb. Could I really have inverted that without noticing? But there is no denying the observation looks much, much better on the assumption that that is what happened.
Jeremy, I will try spreading out my shots. I am using an artifical horizon, though. That limits how low one can observe.
Thank you all again for your help.
Best regards,
Patrick
On Mon, Jan 31, 2011 at 9:50 AM, <Anabasis75@aol.com> wrote:
I will look at your shots in my next exchange Patrick, but I will suggest spreading your shots out a bit more to give a better cut of the lines. I would give at least 2 hours, and preferably three between observations so that there is larger change in azimuth.Jeremy
