WCS fitting
wcsfit matches up objects from an image with astrometric position standards. The transformation between the cartesian and equatorial coordinates is fit. The results are written in both the image header and the catalogue table header in the standard FITS header keywords. A FITS image and an imcore generated catalogue are required input. By default the objects in the catalogue are matched to 2MASS standards which is extracted from the CASU mirror of VizieR. This can be changed by using the optional switches described below.
If the input image is a multiextension FITS file, then the number of extensions in the input catalogue must match with the number of image extensions. wcsfit will fit each image extension in turn.
SYNOPSIS
wcsfit infile incatARGUMENTS
- infile
- Input FITS image.
- incat
- Input FITS table which has been generated by imcorewith source extraacted from infile
OPTIONS
The following options are supported. Default values are specified after th e equal sign.
- --catsrc=viz2mass
- This is the source
of the standard stars to be used in the astrometric fit. The following values
are supported:
- viz2mass
- 2MASS standards are extracted from a VizieR
distribution defined by --site.
- vizusnob
- USNOB standards are extracted from a VizieR
distribution defined by --site.
- vizlandolt
- Landolt standards are extracted from a VizieR
distribution defined by .
- local2mass
- A local FITS copy of the 2MASS catalogue is
searched. The full path to the FITS files is defined by --catpath
- localusnob
- A local copy of the USNOB catalogue is
searched. The full path to the .cat and .acc files is defined by
--catpath.
- localfits
- A locally available FITS table will be searched.
The full path to this table is given by --catpath. The only which are
required in the table are ra and dec. Both of these must be
in degrees.
- --site
- In the event that a VizieR distribution is being
used by --catsrc, then this defines the site of the distribution.
Currently two values are supported: casu uses the VizieR mirror
at CASU in Cambridge and CDS uses the original VizieR at CDS.
- --catpath
- In the event that a local option is specified
in the value for --catsrc this defines the full path to the file(s).
