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From: Francis Upchurch
Date: 2017 Jan 6, 02:02 -0800
Hi David,
I've been doing lunars for about 15 years and still consider myself a very junior apprentice.
Your first try posed a few unknown firsts for me.
I've never used Venus for lunars before (small extra altitude corrections for paralax and refraction ) and no SD.
I've never used artifical horizons either (ignore dip correction)
so assuming I got those bits correct, I tried your sight 1 via the cosine formula in John Karl book page 92. (which I have loaded on a Casio fx-3650P programable calculator)
Unforunately , I think I must have made a mistake somewhere and got a GMT of the sight 08.2.30, which seems way out from the approx 8.23.you mention.
Could you provide your DR lat and long so that I could check against Frank's online site? Also the actual GMT of the sight?
I may have got some of the assumptions wrong.
Normally , with 3 separate readings, I would graph them out, use best fit curve (or hopefully, if all taken within about 5 minutes, a straight line) and choose 3 readings at a single time point. In your case, it looks as if sight 2 may be an outlier which could be excluded?
Anyways, let me know what the correct answer should be and I'll try to figure out where I went wrong and then describe the method in detail for you.
Best wishes and welcome to the lunatic fringe!
Francis