Grayscale_resources

When -gray is selected, gnuplot honors the following resources for grayscale or color displays (shown here with their default values). Note that the default background is black.

  gnuplot*background: black
  gnuplot*textGray: white
  gnuplot*borderGray: gray50
  gnuplot*axisGray: gray50
  gnuplot*line1Gray: gray100
  gnuplot*line2Gray: gray60
  gnuplot*line3Gray: gray80
  gnuplot*line4Gray: gray40
  gnuplot*line5Gray: gray90
  gnuplot*line6Gray: gray50
  gnuplot*line7Gray: gray70
  gnuplot*line8Gray: gray30