I need to export PDF’s with specific colors, and I have one question and an issue I’ve noticed.
The question: Does Rhino support spot colors in PDF export in any way? Is it possible through scripting, is there any plugin that supports it, is it planned, or is it possible through grasshopper somehow?
The issue: When exporting geometry to PDF, I assign specific print colors, but when inspecting the resulting object in the PDF in adobe acrobat, I see much different color values than expected.
For example, if I have these 3 hatches
and I assign their print color using the CMYK color wheel to something like this for the middle blue one: C100%, M100%, Y0%, K0% like so
And I make sure to export to PDF using print colors (not display colors), when I use the object inspector tool in adobe acrobat I see much different color values than I would expect when inspecting the middle blue hatch:
I see C88%, M77%, Y0%, K0%.
Here are the colors assigned to print color in Rhino vs what they read as in acrobat:
black = c0,m0,y0,k100 → c75,m68,y67,k90
blue = c100,m100,y0,k0 → c88,m77,y0,k0
red = c0,m100,y100,k0 → c0,m99,y100,0
Is this a misunderstanding on my part of colors/simulation profiles in acrobat or rhino? I see the colors change depending on the chosen simulation profile, but have not seen one that reflects the values I chose in Rhino.
Is there a document color setting like in adobe products that I haven’t found in Rhino yet, to switch to CMYK for PDF export?
Attached is the Rhino file and PDF exported from Rhino.
hatch_cmyk_test.pdf (7.8 KB)
hatch_cmyk_test.3dm (54.4 KB)