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THE MULE
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Where can find a solar Ephemeris for doing sun shots?  I like to confirm my work.

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Jim in AZ
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Posted by: THE MULE

Where can find a solar Ephemeris for doing sun shots?  I like to confirm my work.

Just what would you be confirming?

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Nate The Surveyor
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Elgin and Knowles used to publish them. I think that the computerized version, drove them out of popular use. I see occasional ones sold as antiques... From 1987 etc.

N

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Bill93
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Jerry Wahl (@jlwahl) used to provide a very convenient one at cadastral.com but I don't think he has done the last few years.  His site recommended  https://celnav.de/longterm.htm

which I haven't used.  You need a current value for delta T (on the order of 70 seconds) to get meaningful answers from sun shots, and I haven't looked for that number. An approximate value would be good enough for Polaris, especially if near east or west elongation.

I once used a program called SPADE to do those calculations, so you might check if it is current.

There have been discussion of solars on this forum in prior years that might have some useful information.  Try a search.

One discussion of methods is here

https://rplstoday.com/community/surveying-geomatics/solar-observation-method-comparison/

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LES
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 LES
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I also still frequently do solar observations along with GNSS observations.  Jerry Wahl no longer provides an ephemeris.

Try this link to the University of New Mexico, Kurt Wurm, Ph.D., P.L.S. for his ephemerides.

Ephemrides

 

 

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THE MULE
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I survey in grid using my JAVAD TRIUMPH-LS GPS.  Then I rotate my survey to True North in my COGO program (Traverse-PC). I test the rotation every way I know how.  I would be confirming the rotation with a sun shot.  I have used the TRIUMPH-LS for about 5 years but it still so awesome to me that I feel lost.  I was a rodman helping with sun shots in 1958.  Also, I have keep Epidermis on file for many years.  I consider Nate the Surveyor to be one of the greats using the equipment that I use.

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Bill93
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Posted by: THE MULE

 I have keep Epidermis on file for many years.

Autocorrect strikes again!

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