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1. Re: Hidden output intent in PDFs by InDesign CS2
rob day Jul 16, 2009 5:53 AM (in response to Gernot Hoffmann)It sounds like the warning is referring to the Output Intent which is required by a PDFX standard, not a color conversion rendering intent.
The PDFX standard requires there to be an output intent (the intended destination) rather than a document color profile. The idea is to prevent unwanted or accidental color conversions at output. So, in the case of PDF/X1-a everything is forced into CMYK or spot on export and no profiles are included—just the output intent. In that case the document CMYK values are always output. If there's no Output Intent included the PDF would not be PDFX compliant.
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2. Re: Hidden output intent in PDFs by InDesign CS2
Gernot Hoffmann Jul 16, 2009 6:15 AM (in response to rob day)Rob,
thanks for your reply, but it isn't really related to my question.
A good occasion for a further clarification:
a) I'm printing often PDFs by large format RIP which contain
CMYK graphics and RGB images. In such a case a global
Output Intent would be quite useless.
I can define Profiles and RIs (Rendering Intents) for
-RGB vector
-RGB raster
-CMYK vector
-CMYK raster
-Gray vector
-Gray raster
but nothing for Lab !
b) I'm familiar with PDF/X. For offset I'm using PDF/X-1a with
exactly one CMYK profile for the conversion and the respective
Output Intent.
Attention: the Output Intent doesn't affect the print (print-ready
PDF/X-1a).
c) the RI for Lab is derived from the 'hidden RI' , which is a result
of the color settings in InDesign. This hidden RI affects the
print result.
d) In Acrobat 8 I cannot detect the RI nor can I change it.
Truly hidden.
Best regards --Gernot Hoffmann
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3. Re: Hidden output intent in PDFs by InDesign CS2
rob day Jul 16, 2009 6:32 AM (in response to Gernot Hoffmann)I'm just pointing out that there's a difference between the terms rendering intent and output intent and from your first post it sounds like Acrobat is complaining about a missing Output Intent (set in the export Output tab) not rendering intent
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4. Re: Hidden output intent in PDFs by InDesign CS2
Gernot Hoffmann Jul 16, 2009 9:40 AM (in response to rob day)No, there is no complaint or warning by Acrobat.
A PDF can exist happily without an Output Intent.
Output Intent for a PDF: a profile which is valid for all ingredients
of the PDF. Useful mainly for PDF/X-1a.
Rendering Intent: a choice of RelCol, AbsCol, Perceptual
or Saturation (always meaningless nowadays) for the application
of a somewhere else defined profile.
Concerning my inquiry: the PDF doesn't have an Output Intent,
but it contains a HIDDEN Rendering Intent.
Such a feature is - as far as I know - nowhere explained by
Adobe docs.
Best regards --Gernot Hoffmann
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5. Re: Hidden output intent in PDFs by InDesign CS2
Jeffrey_Smith Jul 16, 2009 12:20 PM (in response to Gernot Hoffmann)The Preflight functionality of Acrobat 9 is much more comprehensive and improved from Acrobat 8. There is a fixup profile that will change the existing rendering intent to whatever you like (RelCol, AbsCol, Sat, or Per). You can apply this to all objects or certain types: (image, text, vector). As well as fixup profiles, there are check profiles to examine document for the various rendering intents.
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6. Re: Hidden output intent in PDFs by InDesign CS2
Gernot Hoffmann Jul 16, 2009 10:27 PM (in response to Jeffrey_Smith)Thanks, very helpful and probably correct.
But if the Rendering Intents can be defined or re-defined by Acrobat
then this will cause new problems if these settings are in conflict
with similar settings in the RIP.
So far, I'm defining everything in the RIP - except for Lab, where the
rendering is based on the hidden intent.
I'm already in contact with the RIP manufacturer. The solution, IMO:
1. Add choices for the RIs of Lab data, vector and raster.
2. Use always 'RIP RI overrides PDF RI'.
Best regards --Gernot Hoffmann


