Hello, I cannot fix image quality e.g. generated with filled.contour(). Whether I use tiff, png, jpeg, or pdf I always see vertical and horizontal lines at every grid increment on the plots like the attached. There is no problem when I plot in x11. How to fix that? Thanks, Mark [image: Inline image 1] _______________________________________________ R-SIG-Mac mailing list R-SIG-Mac@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-mac