Accuracy of Output Preview in Acrobat

[jethrodesign]

Hi. We received a PDF/X-4 proof from a printer of an Illustrator file we sent to them. I'm trying to check color against the master Illustrator file, which was all generated CMYK artwork in Illustrator with the printer's ICC profile assigned. In Illustrator I preveiw the file with Proof Colors set to the printer's assigned profile and have Overprint Preview turned on.

In Acrobat I'm using the Output Preview dialog to try to soft proof the file. It has the Simulation Profile set as a slightly different name than the printer's profile we have used, so not sure if it's a completely different profile that they have assigned. When I first open the dialog and check a few color callouts (by hovering over elements), the numbers ARE correct. But the file definitely looks different in Acrobat than what I'm seeing from our master Illustrator file.

But here's where I may not be following how the 'Simulation Profile' works in Acrobat. When I change that from the default (the alternate named printer profile) to our local version of the printer's ICC profile, the preview doesn't change at all. BUT the color callouts DO change. I've also tried changing that to numerous other output profiles (e.g., SWOP, GRACoL, other printers, etc.). In each case, the preview stays exactly the same, but the color callout numbers are changing. So it seems like it's doing a 'convert to profile', instead of just simulating how the embedded CMYK values would output on different devices. In Acrobat, there is no 'Preserve CMYK Numbers' like you have in Illustrator (from what I can tell).

- Am I missing the point of how the Output Preview works in Acrobat?

I was hoping to have it show me how the file would look if output to different devices, but it seems to show how it would keep the overall color the same by changing the CMYK values. 

- Any way to modify the behavior in Acrobat so it follows how the other Adobe products tend to work (showing how color will shift when selecting different output profiles)?

Thanks!

[Bob_Hallam]

Seems Acrobat is using the profile Embedded in the document which is different from the one used in Illustrator.  No way to change that in the PDF without PitStop or Esko add-on tools.  So The best solution would be to supply the correct ICC profile to the client and have them open up a new document the same size at the one they are fixing using those new settings, then copy all the elements from the old into the new and save a new PDF.  

[rob day]

The current version of AcrobatPro 2020.006.20042 displays the Separation values for DeviceCMYK color (CMYK with no profile) with no conversion, and will adjust the preview depending on the Simulation Profile. The affect of the Simulation Profile has not always been consitent in older versions of AcrobatPro

PDF/X-4 and PDF/X-1a exports document CMYK colors as DeviceCMYK (no profile), but includes the Destination or Document CMYK profile as an Output Intent Profile. By default the Output Intent is used as the Simulation Profile in Acrobat.

So if the provided PDF is actually to a PDF/X standard, the default Simulation Profile will have an Output Intent: prefix. AcrobatPro will use the Output Intent profile provided with PDF/X as the source profile, and if you choose a different Simulation Profile the Separation values will show the conversion from the output intent profile to the selected simulation profile.

If a PDF is exported with Document CMYK as the Destination and Don’t Include Profiles as the the Profile Inclusion Policy, then the Separation values will not change and the preview will change depending on the Simulation Profile.

[Test Screen Name]

"I was hoping to have it show me how the file would look if output to different devices," Yes, you're missing the point, I think because it IS showing you how it will output to a range of devices - which will all output the same. You say that you have tagged colour in your PDF (tagged = profile applied). When you output CMYK or RGB data, that has a profile, the output process MUST convert to the profile of the actual output device. The colour is therefore preserved as closely as the conversion will allow. " So it seems like it's doing a 'convert to profile', instead of just simulating how the embedded CMYK values would output on different devices. " Yes, exactly so, that's what it MUST do. If you want to drive the CMYK inks directly you MUST send untagged information (no CMYK profile). CMYK to CMYK conversion is often undesirable, especially between very similar profiles, but unless the RIP has special setups, we are stuck with it. Other products offer you the choice, as a designer, to preview the effects of future choices; when you have a PDF it's too late, the choices were already made.

[rob day]

- Any way to modify the behavior in Acrobat so it follows how the other Adobe products tend to work (showing how color will shift when selecting different output profiles)?

One other thing to note, if you place a PDF/X-4 or PDF/X-1a back into either Illustrator or InDesign the PDF’s Output Intent profile is ignored, and assigning different profiles to the document will change the appearance of the DeviceCMYK objects in the PDF, which I think is what you are looking for.  But why would your printer export a PDF to the X-4 standard, and then output to a profile that conflicts with its Output Intent?

[jethrodesign]

Hi, thanks a ton for the informative responses! Much appreciated.

The proof we received was indeed a PDF/X-4 file with the 'Output Intent' profile different from what they sent us to use as their output profile (and what we adjusted all colors for). So, yes, all color was DeviceCMYK or DeviceN. And the color numbers (when inspected in Output Preview) were the correct values that we had applied. It was just that color 'display' was much different from what we had sent, due obviously to the different Output Intent profile.

I guess I was just misunderstanding how the 'Simulation Profile' was intended to work. I thought the color numbers/values set in the file would remain the same, and the display would change to show how those numbers would output on different devices (similar to Illustrator/InDesign Proof Colors). So I was trying to see if I selected as the Simulation Profile our original output profile if the display would shift to matching our Illustrator file.

NOTE: I DID have an older version of Acrobat (X Pro), and that is how it behaves when changing the Simulation Profile (the color display changes based on the output device selected, numbers remain the same). So this must be a new (opposite) way that Acrobat DC works. That's probably my confusion, along with the knowledge that a CYMK-to-CMYK conversion is not usually recommended, which is what Acrobat DC is indicating. Dont' suppose there is a way to change preferences or something to get DC to act like previous versions did?!?

- But why would your printer export a PDF to the X-4 standard, and then output to a profile that conflicts with its Output Intent?

So this is our million $$ question.

- Would it be common for a printer to select the PROOFING DEVICE'S output profile, rather than their final press output profile, when creating a digital proof for client signoff?

Unfortuantely, these are being printed overseas, and there is a bit of a language barier when communicating with them. And the client doesn't really understand the technical aspects & value of color management, so they're wondering why we're spending so much time on it. So we have to tread a bit carefully here.

[rob day]

What is the PDF/X’s Output Intent profile, and what is the profile you have assigned to the InDesign layout? Obviously one of them has to be wrong. If you go back to the InDesign file and assign the PDF’s output intent as the document’s CMYK profile, do the ID and Acrobat previews match?

I think you would have to assume the printer is not going to convert their PDF/X to yet another profile at output, and the numbers you are seeing with the Output Intent set as the Simulation profile will output unchanged. If there is a CMYK-to-CMYK conversion at output it is usually easy to spot (i.e., black only grays would convert to 4-color). In the end you can’t prevent a printer from making conversions at output— even an all CMYK PDF with no source profiles could be converted by assigning an assumed CMYK profile (i.e., SWOP).

[jethrodesign · Accepted solution]

Hi, just an update here. In the end, it appears that the printer assigned the incorrect profile (it was their working space rather than the output profile assigned to the document) when making the initial PDF/X-4 they sent us. They denied applying the incorrect profile, but we responded with screenshots showing the wrong one being applied.

We've since received a new digital proof from them showing one of our colors that is used on some smaller type over background being converted to the corresponding PMS spot color. They're saying to ensure proper registration (it's being printed rotogravure). On this proof, the proper output intent WAS applied, so all seems well and it was a bit of a fire-drill for nothing. We're now waiting to hear their reasoning for needing to use a spot color to ensure registration in this one color...

I suppose I now understand that the Simulation Profile works differently in Acrobat DC, so I'll just have to watch for that. And I suppose I can open files in older Acrobat to see the behavior I was expecting if necessary.

Thanks for the help here!