Subject: Re: Star map equations

From: [email-masked] (Dick Koolish)
Date: 13 Sep 1993 14:11:33 GMT

[email-masked] (Peter Larson) writes:

>Does anyone know the equations for converting RA/Dec or Lat/Long values
>into a conic projection? I have derived my own, but they are very
>complex, so I am assuming that there are simpler equations available.

>Also, I am interested in any other form of projection formulas that are
>commonly used.

There is a whole projection library available.  It's at:

    charon.er.usgs.gov

in the directory:

    /pub

and is in the file:

    PROJ.4.1.3.tar.Z

---

From: [email-masked] (Don Wells)
Date: Mon, 13 Sep 1993 18:46:19 GMT

In article <[email-masked]> [email-masked] (Dick Koolish)
    writes:
 DK> [email-masked] (Peter Larson) writes:
 DK> 
 DK> >Does anyone know the equations for converting RA/Dec or Lat/Long values
 DK> >into a conic projection? I have derived my own, but they are very
 DK> >complex, so I am assuming that there are simpler equations available.
 DK> 
 DK> >Also, I am interested in any other form of projection formulas that are
 DK> >commonly used.

 DK> There is a whole projection library available.  It's at:
 DK> charon.er.usgs.gov in the directory: /pub and is in the file: 
 DK> PROJ.4.1.3.tar.Z

Another interesting reference, one particularly adapted to
astronomical needs, is the file

	fits.cv.nrao.edu: /fits/documents/wcs/ wcs.ps.all.Z
--

  Donald C. Wells           Associate Scientist       [email-masked]
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