Q:  What is the depth of the line at 6546 Angstroms?

         The continuum has a level of about 9700 counts,
            while the bottom of the line is at 3000 counts.

                       (9700 - 3000)
               depth = -------------  =   69 percent
                          9700


  Q:  What is the depth of the line at 6580 Angstroms?


               depth  =   about 7 percent