Changes
/* For IRAF users */
** Use the QL output as a reference. For example, a useful way is to plot the ascii wavelength solution in some interactive plotting window, like python.
** Then simply, select a few bright, well-spaced lines, hover the cursor over them, and read off the wavelength coordinate.
** Now, run '''IRAF - twodspec - identify''' on the corresponding raw 2D image. Select the same line and input its wavelength as just read off the plot. The solution is good to within a couple of Angstroms, and there are sufficient lines in the arcs that this should work well. ''Hint: remember that the raw and 1D Extracted spectra are flipped. A good trick is to reverse the plot window in IRAF with 'w' 'e' 'e' by selecting from bottom right to top left'''
** Repeat for several lines.
** When happy, automatically add all the lines (press "l").
