Compute a test FITS image.

%  tim_stripes.sh --help  

usage: tim_stripes.sh 1.0 25.0 test.fits [-v] [-h]  
arg1 - column 1 value 
arg2 - column 256 value 
arg3 - name of output test image
Additional options: 
 -v = print verbose comments and run in debug mode 
 -h = just show usage message  

You can read some old descriptions HERE.