Check if PDF is CYMK or RGB or "untagged"

Report · Mar 09, 2022

Hello,

I am confused because I have been working similarly for 6 different files in illustrator - they are all in CYMK color space and I converted them to the typical Web Swop 2 ICC profile. I saved these out first with the "high resolution print" specification and gave them a X3 standard. Content with the PDFs, I went to check the collection in Bridge (metadata) and to my dismay, a couple of them were marked as CYMK, one was RGB, and the others were all "untagged". Upon asking, I was told by someone that Bridge is not reliable regarding this. Personally, I find that hard to believe.

I am trying to check the documents in Adobe Acrobat, but some people mentioned an "Advanced" tab... I cannot find this anywhere. I only have preflight options (don't seem useful in this case) and an "info" i to the left of the document... this doesn't say outright what the document is, but it recognizes if the document fits to a PDF standard and states the "preferred target ICC profile"... Unfortunately, several of my documents are coming up blank, even though I did specify X3 for each. I am wondering as to why it is not more obvious regarding if the document is RGB / CYMK or unspecified.

Needless to say, by this point, I am very confused. Can anyone tell me how to check to see what my documents actually are? I am assuming that this is important... and that my PDFs should at least say that they are all CYMK.

To make matters worse, I even tried converting the "RGB" document (it is really CYMK but saved out as such) to a specific CYMK ICC profile on save out, and even this did not deter Bridge from reading it as RGB... So I am really at a loss over what is happening.

Thank you in advance for helping me set this straight!

Sincerely

April

Report · Mar 09, 2022

If Bridge is telling you that a PDF is RGB, or a PDF is CMYK, Bridge is certainly not to be trusted. Because a PDF is a mixture of things, which can be RGB or CMYK or Lab or other things. Many apps give complete nonsense - rather than saying they can't tell you, they make up some junk.

The Advanced tab in Acrobat was removed over 11 years ago. I think you may be trying to follow some very old advice. If you need to check whether a PDF contains RGB (not that it *is* RGB, only whether it has any RGB in it - you might call this "all CMYK" though it still could have Lab, or spot colour in it), you can use Preflight. Be sure to follow instructions written for YOUR version of Acrobat DC.

Report · Mar 10, 2022

Okay, thank you, that is helpful. I was beginning to suspect that Bridge is indeed telling me nonsense. I found an option to convert my colors to the Web Swop 2 Profile in the Adobe Acrobat Preflight... this gives me some peace of mind, but I would have preferred to leave the ICC profile as preferred and not what now seems embedded.... assuming that there is some difference there. At least now I know that all elements should be in the same color space.

I would still like to see a more general identifier that my document is indeed set in general to CYMK... is there really nothing that shows this? - I find it super odd.

Also, this is off-topic, but I have an issue with overprinting. The printer said that I should have max ink coverage of 240%. I have areas that exceed this, and I would love to understand how I can fix them (possibly in Adobe Acrobat Preflight?). I don't have a specified ICC profile from the printer, and I am wondering if this is how these issues are normally fixed, or if there are also other ways... In general, my PDFs have been printing alright, so I wouldn't call this a dealbreaker. It is very important to me that the colors do not shift badly... but if there is a reasonable way to fix this, I would love to get it right. Thanks!!!

Report · Mar 10, 2022

By the way, I have been referencing this window.

Report · Mar 10, 2022

" I would have preferred to leave the ICC profile as preferred and not what now seems embedded"

There isn't such a thing as a preferred profile in any normal PDF. It's either tagged or it isn't, and if it's tagged the profile is embedded (so it works on other people's systems). HOWEVER, there is a complication. PDF/X has the idea of an "output intent" - as in your screen shot. PDF/X requires this. The output intent is "here is an embedded profile to use for any untagged colours in the file". So the file is tagged, in effect, but not all the colours are changed. There may be workflows (not using PDF/X) where the difference is important.

" ink coverage of 240%. I have areas that exceed this, and I would love to understand how I can fix them .... I don't have a specified ICC profile from the printer," Here's how it often works.

1. The designer works entirely in tagged RGB. (Designing in CMYK is seen as obsolete in many workflows, but not all printers have caught up!)

2. The printer provides a profile (and if they can't, common advice is to run away because the printer has 20 year old ideas of how to do things).

3. You or the printer convert to the profile, always being sure your master is saved as RGB. One of the things in the profile is the ink limit. This isn't a number in the profile; it just has rules for converting RGB to CMYK which automatically use the right amount of ink. (If you aren't using this workflow, and just try to reduce ink limits where it's a problem, you're not likely to get the best colour reproduction.)