gif print black on black in FC6

[William John Murray]

  Hi guys,
            I have a problem printing some graphs. They are gif files,
with a pale, (but not white) background. Both eog and gthumb have the
same problem, as two two different FC6 boxes (i386 / x86_64) on two
different postscript printers: The background is coloured black. The
foreground is also very dark, so the whole thing is almost black.

 Very cool, I'm sure, but it uses a lot of toner to little purpose.

   Does anyone have a suggestion?
  Thanks,
    Bill