Jamie,
> Here is a bit of heads-up with regard to the CONVERT package and what we
> at the JCMT foresee as our upcoming needs for ACSIS data.
So you will need to write these other WCS encodings - will you also need
to *read* them?
Do you have any rough idea of when you would need these new facilities?
David
> 1) FITS and NDF. FITS2NDF is currently successful at converting ACSIS
> FITS cubes to NDF. This stage is essential to us as we plan on doing
> all of our ORAC-DR controlled manipulations on datacubes using NDF
> files and packages such as MAKEMOS and WCSALIGN. However, there is a
> (firm) plan to have the ACSIS-DR system write NDF natively (once large
> file support is available), bypassing the FITS stage. The NDF created
> will have all the ACSIS specific info in the FITS header.
>
> 2) At the end of the ORAC-DR pipeline, the NDF cube will (optionally)
> be converted back to FITS for observers who want FITS files. Here is
> where the fun starts. Currently, AIPS++ does not understand WCS/FITS
> paper III cubes and probably will not do so for a substantial
> time. While currently AIPS++ remains our off-line reduction package of
> choice, uncertainty surrounding the AIPS++ project means that we want
> to be able to make FITS cubes that can be read into a variety of other
> packages (e.g. classic AIPS, CLASS), giving users more freedom.
>
> Currently, running ndf2fits on an ACSIS ndf without any options will
> gives us a nice standards compliant FITS, but we need to support other
> packages via the ENCODE option.
>
> Ideally, we would like
>
> (i) An ENCODING=FITS-AIPS++ option (for AIPS++). This may turn out to be
> identical to the ENCODE=FITS-AIPS, but I need to investigate this
> further. This is our priority item.
>
> (ii) an ENCODING=FITS-CLASS option, for CLASS import. Again, I need to
> investigate what sort of FITS class expects. Here is the spec for
> CLASS fits headers:
>
> http://www.iram.fr/IRAMFR/GS/class/node45.html
>
> Note the IMAGFREQ support for DSB instruments.
>
> (iii) an ENCODING=FITS-SD. Support for NRAO SDFITS (used by AIPS++ in
> its single spectrum handling tools). This will require work in CONVERT
> in addition to AST since SDFITS uses binary tables for each
> spectrum. This might require more work as each spectrum is held as a
> binary sub-table. Could be a new command e.g.NDF2SDFITS. The SDFITS
> standard is described here.
>
> See eg http://www.cv.nrao.edu/fits/documents/drafts/dishfits/sdfits.ps
>
>
> Regards,
> Jamie Leech.
>
----------------------------------------------------------------------
Dr David S. Berry ([log in to unmask])
STARLINK project | Centre for Astrophysics
(http://www.starlink.ac.uk/) | University of Central Lancashire
Rutherford Appleton Laboratory | PRESTON
DIDCOT | United Kingdom
United Kingdom | PR1 2HE
OX11 0QX Tel. 01772 893733
01257 273192
|