[fitsbits] creating WCS solution keywords?

[David Berry]

On 8 Jun 2001, Michal Szymanski wrote:

> I used to find the frame-to-RA/Dec transformation coeffs "manually"
> by finding common stars on the frame and corresponding DSS image
> and then calculating some quadratic transformation. I kept the
> coefficients in external tables, using some simple external command to
> compute RA/Dec from frame x/y.
> 
> Now there is a growing number of public-domain software packages that
> can directly use the plate solution coeffs (PLT*, PP*, AMD*)
> stored in FITS header.
> 
> Are there any tools facilitating computing/creation of these
> coefficients for a given frame? I guess they can be created in IRAF
> in the process of "registering" a frame but frankly speaking I'd prefer
> some stand-alone utility not requiring IRAF use.

Starlink GAIA is a graphical tool for manipulating and analysing
astronomical images. One of the things it can do is to create astrometric
calibrations. You can either fit a new astrometric calibration to your
image (using on-line catalogues or images for reference positions), define
a new one using known information (such the image scale and a reference
point), copy one from another image and finally tweak one to make it fit
better.


See:

http://star-www.dur.ac.uk/~pdraper/gaia/gaia.html


David Berry

UK Starlink project