Please set plotting options, checking corresponding flags.
Description of some flags:
"Contour/Shaded plot" – to set contour(by default) or shaded plot.
"Color figure" – to set colored (by default) or black and white plot. This option is valid only for contour plot.
''Reverse color table” - to reverse color table. By default the dark-blue color is used for the minimum and dark-red - for the maximum. This option is valid only for contour plot.
''Logarithmic scale in vertical direction'' – to set logarithmic scale in vertical direction. By default linear scale is used.
"Plot background" – to set plot background - black (by default) or white.
''Output file format''- to set output file format - GIF (by default) or PNG.