PDF Overprint

[tommrz]

We are having issues with several clients being able to view overprints on PDFs. They all want to see PDFs as proofs but cant understand that they need to view these PDFs with overprint preview. We have tried several times to explain to some clients about the various places to turn on overprint simulation but some clients do not seem to want to put in the effort.
My question is...Is there a particular PDF format that will view and print overprint simulation on any clients computer regardless of what platform they are on or what version of Acrobat they are using yet still be small enough to email?

 

[mattbeals]

PDF/X-1a or PDF/X-4. Just down sample the resolution. "Newer" versions of Acrobat Reader should automatically turn on overprint preview.

 

[Lukas Engqvist]

Any PDFx will automatically trigger overprint preview and output intent profile (in ACROBAT or ADOBE READER). Now since there are many other PDF readers there may be an issue.

I use rgb PDF's with about 100ppi resolution flattened and with "simulate overprint" in the PDF creation to send as proofs. It will give a trustworthy simulation, not perfect, but no dissapearing white text that doesn't dissapear in the proof first (this works in any PDF viewer but may give stitching defects at some zoom percentages)

Note that you can include ICC profile if you like for even better control, but it will add to file size... I do all as sRGB.

 

[tommrz]

Thanks...I will give it a go.

 

[Stephen Marsh]

I used to use two methods, depending on various factors:

1) Convert the PDF to a "monitor width" resolution JPEG or PNG of say 800px or 1200px (dependent on content, file size, amount of files etc).

2) Create a PDF/X-4 file with reduced image resolution and JPEG compression (unflattened for smaller file size and forcing overprint view via pdf/x), that would contain RGB and CMYK objects (it did not matter as everything was viewed/printed through the output intent) which used the Callas PDF toolbox "Callas_Small_Fogra39" ICC profile as the output intent. This profile was not used to make press conversions as it was "stripped down", however it was good enough to embed as the output intent for preview purposes in a draft PDF without bloating the file size too much. I would stress that the PDF would need to be opened in the free Adobe Acrobat Reader for accurate viewing.


Stephen Marsh

 

[pkleinheider]

Hi,

as Matt mentioned: "Newer" versions of Acrobat Reader should automatically turn on overprint preview

means

Acrobat 9 and newer.

For that reason I have quite a number of customer (Europe) that are rendering the PDF pages (simulating overprinting) to something like 144ppi images as multipage PDF since these PDFs can even be viewed with Acrobat 4 and no overprinting is needed.

Cheers,
Peter Kleinheider
inpetto premedia consulting

 

[drummerpaco]

When I converted to PDF/X-1a, I could see the overprint on acrobat reader.
Now, when you have transparence effect on overprint, I could still see the overprint and as directed profile color space.
However when PDF/X-1a file will not able to print the PDF file as you see on the screen.
PDF/X-4:2008 is way to go. It solves the problem to print and view the overprint + Transparency.

 

[Lukas Engqvist]

Yes PDFx4 is a higher level abstraction a PDFx1a needs to have "simulate overprint" on in the printer settings, which is not available in Readers.

 

[zoran]

Investing in online soft proofing option might be another solution (costly but effective).
Pixel streaming or other technology used by different vendors accurately displays PDF without worrying about overprint preview on or off in client's acrobat.

 

[Bo3b]

You can change the preferences in Acrobat to show overprint for all PDF's not just PDF/x

 

[drummerpaco]

But cannot see in Reader which most of people, customer, do not have one.

 

[leonardr]

But cannot see in Reader which most of people, customer, do not have one.

Reader 9 and later have the EXACT SAME PREFERENCE for controlling Overprint viewing.

 

[Stephen Marsh]

Reader 9 and later have the EXACT SAME PREFERENCE for controlling Overprint viewing.

Agreed.

That being said, it is hard to get folk to change their defaults - which is why PDF/X is a good choice.

Stephen Marsh

 

[prepressguru]

Any PDFx will automatically trigger overprint preview and output intent profile (in ACROBAT or ADOBE READER). Now since there are many other PDF readers there may be an issue.

I use rgb PDF's with about 100ppi resolution flattened and with "simulate overprint" in the PDF creation to send as proofs. It will give a trustworthy simulation, not perfect, but no dissapearing white text that doesn't dissapear in the proof first (this works in any PDF viewer but may give stitching defects at some zoom percentages)
View attachment 1965
Note that you can include ICC profile if you like for even better control, but it will add to file size... I do all as sRGB.

Lukas, I take it these are the settings from the native application. What about if you have a PDF already say from a prepress workflow? Do you apply similar settings within Acrobat?

I've found our workflow does not always produce a small enough PDF for email (never mind about the overprint) and I am always playing around with the settings. Lately I have been leveraging more of the preflight tools in Acrobat to accomplish this.

p

 

[Lukas Engqvist]

It is possible to refry the PDF, with "simulate overprint" when exporting to PS, and then redistill with colour management to sRGB (yes I am aware that it will cost me bright cyan). This is effectively giving you a flattened screen dump with overprint enabled. You'd need to test it with your workflow, but I think it should work.

 

[zoran]

I would be afraid to refry PDF for the sake of reducing size.
You can use acrobat.com or any other online service to upload PDF as is, rather than refrying it as you might affect PDF in process so it does not represent actual printed PDF 100 %

 

[leonardr]

It is possible to refry the PDF, with "simulate overprint" when exporting to PS, and then redistill with colour management to sRGB (yes I am aware that it will cost me bright cyan). This is effectively giving you a flattened screen dump with overprint enabled. You'd need to test it with your workflow, but I think it should work.

NO NEED to refry with Acrobat 9 Pro and later!

The Transparency Flattener dialog also includes an option to "Flatten Overprinting" (aka rewrite the file with "simulate overprint" on). You can also use Preflight to do this either manually, in Batch/Action or via Droplet.

 

[Lukas Engqvist]

@leonardr true, some of the work arounds from acrobat 4 are still stuck in my memory triggered by problems that arise, and I forget the more current fixes, thank you for reminding me. For the problem with a customer that is not seeing overprint a droplet to change to "simulate overprint" would be a great alternative.

 

[CHM]

A other solution in this discussion could be to prevent using the (old) overprint settings in your native files, and change the to a transparency alternative like Multiply or Darken.
These will always show up in Acrobat like they do in your native application.
The only problem with these files is if your client want to print these files and his printer (RIP) is not up to date, the result on print wont be the reality.

 

[Lukas Engqvist]

@CHM not to mention that you get different results depending on if you have RGB or CMYK as transparency blend space and how you have BCP configured in the rip.