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Re: An azimuth nomogram: what's under the hood?
From: Robin Stuart
Date: 2018 Mar 13, 10:07 -0700
From: Robin Stuart
Date: 2018 Mar 13, 10:07 -0700
Tony,
The only lesson you need to take away from the video is that multiplication can be done by connecting points on a parabola with a straight line. In this case the relevant equation is
sin d = cos L cos Z
where d is the declination, L latitude and Z azimuth. The three scales can be produced by plotting the curves (0, sin d ), (k cos L, cos2L) and (k cos Z, cos2Z) for some arbitrary k,
Regards,
Robin Stuart
