On 5/18/25 06:46, jbf wrote:
I have to say that I remain confused about the intent statement. Let me explain my confusion. Let's say my preamble says:
\setupbackend [format=PDF/X-1a:2001, intent=default]
(or I leave the intent blank), using the latest Context version 2025.04.28 14:29 LMTX, my log file tells me, amongst other things:
backend > profiles > using color intent 'sRGB-v4.icc'
Hi Julian, this is exactly what https://www.pragma-ade.com/general/manuals/standards.pdf#page=3 (near the end of the page) explictly states.
*but I thought that rgb and transparency were not appropriate for PDF/X. Am I right about that?*
According to https://en.wikipedia.org/wiki/PDF/X, colors in PDF/X-1a should be CMYK or solid ones (no color composing points of different basic colors). I think RBG and transparencies were adopted in later versions.
If I change intent to one of the color profiles listed on https:// wiki.contextgarden.net/Input_and_compilation/PDF/PDFX all of them cause an error,
And what happens if you set "intent=cmyk" (from the same page as above)?
There is clearly something I do not understand about how I should indicate the intent. If the items on the web page indicated above are 'pre-defined output intents', then why don't they work for me? Can someone show me exactly how I should fill out the intent= part of \setupbackend so that I get a valid PDF/X, or indeed can I simply ignore it and just put in default?
"intent=cmyk" should add a CMYK color profile: CGATS001Compat-v2-micro.icc (https://github.com/saucecontrol/Compact-ICC-Profiles?tab=readme-ov-file#cmyk).
Anything I send to print is for grayscale or BW printing, not color. What I currently do is to use an older 2022 version of ConTeXt where I have the SWOP profile, and I think it is simply ignored. It certainly does not cause compilation issues. but the more recent versions do.
According to https://www.pragma-ade.com/general/manuals/standards.pdf#page=3, with "intent=cmyk" there is also a gray scale profile added: sGrey-v4.icc (https://github.com/saucecontrol/Compact-ICC-Profiles?tab=readme-ov-file#grey...). BTW, there might be a minor issue with this in the source. But I’m going to ask in a new thread, since it is really independent. I hope it helps, Pablo