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To Resample Calibration Images

 

The ROSAT exposure and background maps are 128128 images linearly replicated to yield 512512 arrays. The user can re-sample these maps using IRAF tasks as follows:

  cl> images
  im> magnify rp110590_max rp110590_mex_demix dx=4 dy=4 inter=linear     # yields a 
                                      # 128*128 exposure map, i.e., true resolution 

  im> magnify rp110590_mex_demag rp110590_mex_15 4 4 inter=spline3       # yeilds a 
                                                                 # 512*512 map with 
                                                    # 15'' pixels generated using a 
                                                   # 3rd order spline interpolation

The user can apply different interpolation functions to obtain the optimum result. Please note that the size of the final image may not be exactly 512*512 due to edge effects of the binning (type help magnify for more information). skypix can be used to check the sky coordinates against the original image.



Belinda Wilkes
Wed Jul 5 04:38:15 EDT 1995