[fitswcs] Polarization codes

[Steve Allen]

On Fri 2008-03-28T14:39:09 +1100, Mark Calabretta hath writ:
> On Thu 2008/03/27 14:09:40 -0000, Paddy Leahy wrote
> in a message to: Mark Calabretta <mcalabre at atnf.csiro.au>
> and copied to: fitswcs at nrao.edu

Did anyone else get that message from Paddy Leahy?
I've checked my junk filters and I didn't see it, and it's not
in the fitswcs archive.  But turning to Mark's reply

> in practical
> terms you have de facto title to a bit of the FITS namespace, in this
> case BTYPEia, BUNITia, BSCALia and BZEROia.  In any case, these keywords
> do not conflict with any other documented FITS usage so noone can stop
> you from using them; this is the concept of private extensibility
> extolled by Don Wells.

I have to say that I find all of these Bxxxxxxx keywords to be
completely in accord with FITS from its inception.  We may be annoyed
by the 8-character keywords, but examples like this show that we are
not limited by them.  I look forward to the refinement of these
and the creation of some conventional values that get into standards.

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
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