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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Longhand Sight Reduction
From: Greg Rudzinski
Date: 2014 Nov 23, 13:05 -0800
From: Greg Rudzinski
Date: 2014 Nov 23, 13:05 -0800
Hanno,
The formula varient that you show is actually what I used to format the index card reduction. It works well to save space. For same name N=hav(L-D), P=hav(L+D). For contrary name N=hav (L+D), P=hav (L-D). For calculator reductions Hc= Arc Sin [1-2(x), x=N+(1-Q)*havLHA.
I prefer to us different letters where n=(L+/-d),m=(L+/-d), P=(1- (n+m))*havLHA, ZD=Arc hav(n+P). This way when Bowditch is consulted there is better agreement.
Greg Rudzinski
From: Hanno Ix
Date: 2014 Nov 23, 10:10 -0800
Greg,
there is a form of the hav-Doniol some people might prefer.
Mathematically, there is no difference to the original formulation.
Here it is:
define: N = hav( L - D );
define: P = hav( L +D );
define: Q = N + P;
hav(s2s) = N + ( 1 - Q )* hav(LHA);
