WCS paper 2

[Mark Calabretta]

Paper II in the WCS series "Representations of Celestial Coordinates in
FITS" is now available for comment.

The draft dated 1999/04/20 is available immediately from my home page
http://www.atnf.csiro.au/people/mcalabre.  By the time most people read
this it should also be available from Eric's ftp area
ftp://ftp.cv.nrao.edu/NRAO-staff/egreisen.

Apart from changes required for conformity with Paper I, the main
changes have been to clarify some subtle points, explain why some things
had to be done as they were, provide additional background material, and
provide a further example of header interpretation and three examples of
header construction.  At the request of the optical community, the TAN
projection has been generalized with the addition of a distortion
function and an example is given of translating a DSS header into it.
There was also a minor correction to Eq. 45 for Airy's projection.  Some
material which should be common knowledge was removed to simplify the
paper slightly.  Some alternate and less useful forms of the projection
equations were also removed.  The graticules are now all drawn to scale.


Thanks,

Mark Calabretta (mcalabre at atnf.csiro.edu)
Eric W. Greisen (egreisen at nrao.edu)