NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dreisonstok Compliments Weems
From: Hewitt Schlereth
Date: 2009 Dec 15, 10:20 -0400
From: Hewitt Schlereth
Date: 2009 Dec 15, 10:20 -0400
Neato, Gary. Hewitt On 12/14/09, Greg Rudzinskiwrote: > I would like to add this rule for all bodies : > A. If Latitude and declination are the same in name use Dreisonstok. > B. If Latitude and declination are contrary in name use Weems. > > This will keep things positive. > > > On Dec 14, 12:50 pm, Greg Rudzinski wrote: > > In the process of comparing short methods of non electronic sight > > reduction it came to my attention that the subtle differences between > > Dreisonstok and Weems tables actually compliment each other very well > > thus making it worth while having both copies at hand. The beauty of > > having both lies in the treatment of declination as a plus or minus. > > What I like to do is add instead of subtract where ever possible so by > > using Weems in the northern hemisphere fall/winter and Dreisonstok in > > the northern hemisphere spring/summer addition of declination is > > maintained. The other beautiful compliment is the graph vs. tabular > > azimuth determination. When speed is needed then the Weems graph is > > used. When accuracy for compass error determination is needed then > > Dreisonstok is used. Once an Hc is determined by Weems then extracting > > Z' and Z" from Dreisonstok is simple. > > -- > NavList message boards: www.fer3.com/arc > Or post by email to: NavList@fer3.com > To , email NavList+@fer3.com -- NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com