ds9_xymatch
  1. A short and practical example.

Derive a coordinate transformation between two input FITS images. The user identifies targets common to the two images using a 2-frame ds9 display. The only thing assumed is that:

  1. A ds9 window is already opne (see ds9_open),
  2. The two images specified on the command line reside in the local working directory.

This code is in flux, and detail information should be viewed with the online documentation: 

 
% ds9_xymatch --help  
  
Help Information for:  ds9_xymatch

Usage: ds9_xymatch m1.fits m2.fits
arg1 - name of fits image 1
arg2 - name of fits image 2

I will show: /home/sco/sco/codes/bash/HELP_FILES/ds9_xymatch.help

  **** This DOC is in flux!!! ****
As long as you retain the region files and the current transofrmation solution file, this could be run repeatedly in order to iteratively improve the solution.



A short and practical example.
I process two images with ds9_xymatch for the purpose of transforming one to the system of the other. 
 
% ds9_xymatch Rsco2039.fits Rsco2042.fits  
After the run I have he files: 
TRS.Rsco2039-XY2XY-Rsco2042
TRS.Rsco2042-XY2XY-Rsco2039

A frequent next use would be to use the TRS solution files to 
transform Rsco2039.fits to the coordinate system of Rsco2042.fits: 
% clip_imshift_trs.sh Rsco2039.fits Rsco2042.fits TRANS.fits  

To view the images: 
% ds9_open 900 900  
% ds9_view Rsco2042.fits zscale n 1  
** Then I manually load TRANS.fits and select Frames> Match > Frame > Image 
   to register the images. I can then blink the two frames to insure that 
   they are well registered. 

An even easier way: 
% ds9_open 900 900  
% cat list.2
Rsco2042.fits
TRANS.fits
% ds9_multi_view list.2 1.0 10000.0 

*** Then you can blink the images to verify registration.


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