<HTML dir=ltr><HEAD><TITLE>Re: [Proj] Projection Dev - How to call other projections fromaprojection?</TITLE>
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<DIV dir=ltr><FONT color=#000000 size=2 face="Times New Roman">A spheroid is an ellipsoid associated with a classical datum that ALSO has a geoid model such as: NAD27, Clarke 1866 spheroid; European Datum 1950, International spheroid. Conversely, the Camacupa Datum of Angola has the Clarke 1866 ellipsoid, <EM>etc</EM>.</FONT></DIV>
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<DIV dir=ltr><FONT size=2>Most people ignore the distinction, though. (I suspect through ignorance.)</FONT></DIV>
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<DIV dir=ltr><FONT size=2>:-)</FONT></DIV>
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<DIV style="MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN style="FONT-SIZE: 10pt; mso-ansi-language: DE" lang=DE>Clifford J. Mugnier, C.P., C.M.S.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></DIV>
<DIV style="MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN style="FONT-SIZE: 10pt">Chief of Geodesy,<o:p></o:p></SPAN></DIV>
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<FONT size=2 face=Tahoma><B>From:</B> proj-bounces@lists.maptools.org on behalf of Charles Karney<BR><B>Sent:</B> Mon 10-Oct-11 08:32<BR><B>To:</B> proj@lists.maptools.org<BR><B>Subject:</B> Re: [Proj] Projection Dev - How to call other projections fromaprojection?<BR></FONT><BR></DIV>
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<P><FONT size=2>This may be true is cartography. It's only partly true in geodesy --<BR>some authors make a distinction, e.g.,<BR><BR> W. A. Heiskanen and H. Moritz, Physical Geodesy,<BR> (Freeman, San Fransisco, 1967)<BR><BR>use spheroid to refer to an approximately spherical shape. (This was,<BR>presumably, its original meaning.)<BR><BR><BR>On 10/09/11 19:43, Noel Zinn (cc) wrote:<BR>> "Spheroid" and "ellipsoid" are synonyms for the same thing in geodesy and<BR>> cartography.<BR>_______________________________________________<BR>Proj mailing list<BR>Proj@lists.maptools.org<BR><A href="http://lists.maptools.org/mailman/listinfo/proj">http://lists.maptools.org/mailman/listinfo/proj</A><BR></FONT></P></DIV></BODY></HTML>