Subject: Some quick suggestions...

From: Paul Harrison <"19463::JBVAD::PAH"@NRAO.EDU>
Date: Fri, 10 Nov 89 13:05:46 EDT

As a result of trying to make a header for a single dish FITS format file I have
the following suggestions

1. Make AZIM, ELEV, ZENI the standard names for azimuth elevation and zenith
angle respectively. We decided on AZIMUTH and ELEVATIO in the meeting but these
names do not allow axes to be labeled in the standard fashion including a
projection type.

2. Have the convention that the first matrix is the `main' data matrix when
there is more than one matrix. This is obviously easy to decide if the second
data matrix is ERRORS or QUALITY, or some such type, and if we keep to the
convention that different backends/frontends etc. go on different rows it
should always be easy. Incidentally it might be a good idea to formalize the
names ERRORS and QUALITY.

3. The question of irregularly sampled axes was `finessed' at the workshop. But
after a little thought I have a solution that seems reasonably easy to
implement within the 3d binary tables concept. There is nothing in the format
that stops CRVALn from being an array of dimension MAXISn, in which case the
array can contain the explicit coordinate value of each pixel. This case could
be flagged by setting CDELTn to 0, and CRPIXn having a mandatory value of 1.

That is all for now, although I think I will probably come up with some more
before I am through!

      Paul Harrison (Jodrell Bank)