This is an upgraded version of the gwcs code. It does everything the same (including using Ra,Dec that are predicted from DSS image WCS) with one important difference. Instead of having the user setup the stars regions (circles) in both image frames, this version uses a catalog of star positions to overplot stars in the DSS image of frame #2 (the right-hand image frame). The routine that performs this part of the task is called ds9_2f_with_cat.
% % gwcs_with_cat a.fits STARS.cdfp arg1 - name of fits image file arg2 - name of CDFP file with star positions arg3 - Y/N for file cleaningThe same wcs_setup.sh used in gwcs is called near the end of gwcs_with_cat to construct an input for input to various WCS tasks. The output file always named: wcs_setup.out, and just for completeness we show an example of a wcs_setup.out file here:
% cat wcs_setup.out
{1}
729.000 556.000 190.505569458 41.001049042
{2}
666.000 795.000 190.535110474 41.090896606
{3}
403.000 691.000 190.665115356 41.050914764
{4}
866.000 1538.000 190.432510376 41.369430542
{5}
1483.000 1494.000 190.123840332 41.351387024
{6}
1469.000 1320.000 190.130340576 41.286621094
{7}
979.000 1394.000 190.377288818 41.314800262
The difference between gwcs and gwcs_with_cat is small in approach, but large in practice. In gwcs_with_cat, the user is locating and marking stars in the left-frame only. The right-frame (#2) with the DSS is viewed to simply identify the names of the stars that are designated inthe CCD image. This saves the reducer a lot of time and make its much easier to locate stars over a large area of the CCD image.