Publishers sometimes require electronic figures as tif or eps, and using
the cymk color system. We do everything in rgb. I don't understand
color systems well. What would be needed to give mpl the ability to
produce files using the cymk system?
I don't understand color systems very well, either, but I ran into
this problem when I printed out some color figures recently.
I saved a mpl line plot containing 'r', 'g' and 'b' lines to a PDF
file. The file displayed on-screen as expected, using both Linux
acroread and Mac OS X Preview as viewer. It also printed out as
expected on an HP Color Laserjet via Linux acroread. On the Mac,
however, a straightforward printout resulted in purple instead of blue
lines. The problem disappeared when I selected ColorSync -> Color
Conversion -> In Printer in the print dialog.
When I printed out an OmniGraffle PDF diagram, however, the colors
were messed up using "In Printer" and correct when using "Standard"
color conversion. This forced me to print the color pages in my thesis
containing OmniGraffle diagrams and mpl figures using different
printer settings, which is quite annoying.
There is another option, which makes Linux and Mac PDFs much more
compatible (especially for color), and that is PDF/X-3
(http://en.wikipedia.org/wiki/PDF/X). This subset of PDF forces the
document to include all fonts and color profiles, leaving nothing to
chance. While the file is possibly bigger, it is more likely to
display correctly on all manner of printers and screens. I eventually
converted my Omnigraffle diagrams to PDF/X-3, and now their colors and
shadows appear correct on Linux, while they were psychedelic before.
PDF/X-3 might be a worthwhile standard to follow for mpl figure output
(even only as an option). At least embedding ICC profiles is probably
a good idea.