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Re: Pre Calculating (Hp) For Fixed Angle Reflectors
From: Fran Herranz
Date: 2018 Jun 4, 18:19 +0200
From: Fran Herranz
Date: 2018 Jun 4, 18:19 +0200
Hello,
I had readed this list for years and Bris "sextant" is the reason. I have been thinking a lot about use it easily with simplified tables. Probably the ideas I explain afterwards are only a summary of all I read here.
I assume that is related to the improved number of angles Bris like sextant discussed now in other topic.
Are you proposing a Pub 229 or 249 like tables for every Bris angle? Maybe a lookout table organized in a page for every Bris sextant's angle with assumed latitude in columns, declination in rows that gives LHA and two azimuth (East and West of the meridian)like result. It could be generated after calibrate Bris sextant's angles and would be printed in a tiny booklet.
You only wait for time when object hits horizon. With the difference between tabulated time and actual time you could move the tabulated LoP.
Maybe for standard Bris or a non shaded Bris microscope slide for Moon needs the full range of declinations but for mirror star Bris (two fixed angle mirrors) you need to calculate only for several declinations as many as nautical stars.
I made time ago a spreadsheet for some angles and declinations.
P.S.: Sorry for my English and for so large boring speech.
Fran Herranz
El dom., 3 jun. 2018 19:37, Greg Rudzinski <NoReply_Rudzinski@fer3.com> escribió:
A general question...are precalculated Hp altitudes for a fixed angle reflection (such as the Bris sextant) plotted from an assumed position that is shifted in longitude by the observed time difference converted to arc ? Is the time sight formula to be used for the precalculation ?
Greg Rudzinski
