I've noticed some unusual behavior in Mathematica when exporting plots. If I try to export an ArrayPlot with a frame around it, I notice that the resolution that I export at has no effect on the thickness of the frames even though the rest of the graphics scale as you would expect. Naturally, this means that if I export a plot to a high resolution, the frames are almost completely invisible!

It would be preferable if I could specify a thickness relative to the entire graphic; so that way when I export at various resolution, the frame thickness scales accordingly.

Even when I'm not simply exporting raster images directly from Mathematica, I notice the exact same problem when exporting to an .eps file and trying to scale in Illustrator. All of the graphics scale perfectly, but the frame keeps its same thickness. See the following images to demonstrate what I'm talking about for various scale levels:

: :

The goal is to keep the frame thickness consistent, no matter what I scale the image size to. But clearly that's not happening, and I can't figure out how to fix it! Try it out for yourself and see if you have the same issue. If you do, do you have any ideas?