Each of the filter transmission curves was generated from the data in the trace data files. If you wish to generate your own curves, you can download the trace data files by clicking on the trace data hypertext in the filter data table. The data in the files can be plotted via any one of a number of graphing routines, e.g. the IRAF graph task.

The IRAF graph task is easy to use. In IRAF, type graph filename, where filename is the name of the trace data file. Here is a sample parameter file that is set to plot the B filter trace data. The x-axis is set to start at 3000 Å and end at 6000 Å. The y-axis is set to start at 0% transmittance and end at 100% transmittance. The graph task will autoscale the axes if these values are set to zero (the default). Axes labels and a plot title have also been added. If the parameter file seems a bit overwelming, don't worry. One can generally get by with the default graph parameters.

IRAF graph task parameter file:

      input = "B.a"           list of images or list files to be graphed
       (wx1 = 3000.)          left  world x-coord if not autoscaling
       (wx2 = 6000.)          right world x-coord if not autoscaling
       (wy1 = 0.)             lower world y-coord if not autoscaling
       (wy2 = 100.)           upper world y-coord if not autoscaling
       (wcs = "logical")      Coordinate system for images
      (axis = 1)              axis along which projection is to be taken
 (transpose = no)             transpose the x and y axes of the plot
 (pointmode = no)             plot points instead of lines?
    (marker = "box")          point marker character?
  (szmarker = 0.005)          marker size (0 for list input)
     (logx = no)             log scale x-axis
      (logy = no)             log scale y-axis
       (box = yes)            draw box around periphery of window
(ticklabels = yes)            label tick marks
    (xlabel = "Wavelength (Angstroms)") x-axis label
    (ylabel = "% Transmittance") y-axis label
   (xformat = "wcsformat")    x-axis coordinate format
   (yformat = "")             y-axis coordinate format
     (title = "B filter")     title for plot
   (lintran = no)             perform linear transformation of x axis
        (p1 = 0.)             start input pixel value for lintran
        (p2 = 0.)             end input pixel value for lintran
        (q1 = 0.)             start output pixel value for lintran
        (q2 = 1.)             end output pixel value for lintran
       (vx1 = 0.)             left limit of device viewport (0.0:1.0)
       (vx2 = 0.)             right limit of device viewport (0.0:1.0)
       (vy1 = 0.)             bottom limit of device viewport (0.0:1.0)
       (vy2 = 0.)             upper limit of device viewport (0.0:1.0)
     (majrx = 5)              number of major divisions along x grid
     (minrx = 5)              number of minor divisions along x grid
     (majry = 5)              number of major divisions along y grid
     (minry = 5)              number of minor divisions along y grid
  (overplot = no)             overplot on existing plot?
    (append = no)             append to existing plot?
    (device = "stdgraph")     output device
     (round = no)             round axes to nice values?
      (fill = yes)            fill viewport vs enforce unity aspect ratio?
      (mode = "ql")