I'm trying to use PLPlot to generate some world maps.  I *must* generate a JPEG file, but the jpeg device for the PLPlot version installed in my system produces ugly results.  I thought of using device pngcairo (since png device looks also not good enough), and then convert the resulting png file to jpeg.  The problem I'm facing is that I get a sort of fine grid in the image that I plot.
It would be easier to understand if I say that I get the same effect using device pngcairo with example 16 (shading).  The shade plot generated in this example shows a grid plotted over the shading surface, that is not shown in jpeg/png/win/ps devices.  It seems to be an artifact related to the cairo family of devices.
Does anybody know how to remove this grid?
Thanks in advance,
J C Gonzalez
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