What is the effect of "Output Intent Profile Name", when exporting PDF from InDesign?

Question

I wonder what Output intent profile name means, when exporting a PDF from InDesign. Does it have any effect at all on the result, or is it just a piece of information, a text string, that is stored in the document for the printing company to see?

Comparing two files exported from a document, with "output intent" changed I get No differences in the Compare function of Acrobat DC, but comparing the files binary with "Beyond compare", there are lots of differences. There is the text string with the profile name selected for the Output intent, but also a lot of binary differences, presumably in the photo I included in the document.

The only information I've found about Output Intent is: "Specifies a profile name (usually the Destination profile)."

Nowadays many printing companies suggest that you send them PDF:s with mixed colour spaces – that you should let sRGB profiles remain in colour photos and let CMYK content keep original profiles. Then Colour Conversion is to be set to "No colour Conversion", when exporting the PDF.

Unless you work very closely with the printing company and knows what piece of printing equipment is to be used, and what kind of paper (and from that can decide what colour profile the printing company should use), I can't see that output intent is meaningful.

But on the other hand... the binary differences in my test suggests that there's more to it. So please, enlighten me, what's its purpose?

Thanks, Andreas Jansson

Answer 1

Output intent is one of the most needed features in the print production nowdays.

An output intent describes the final destination device you will use to reproduce the color in the PDF, such as the separations printing device. Output intents override working spaces during viewing and printing, but they do not convert the colors in the PDF.

To make it more simple: by knowing output intent you can understand for what color space file was created originally.

Most common output intents will correspond to coated/uncoated papers, web/sheetfeed production, special papers (like newspaper paper, yellow paper, etc.) and other materials.

So in the end, when file is actually printed, it doesn't matter so much, are there RGB, CMYK or Spot colors. The only thing that matters is output intent. If you know that, then color conversion software will do the rest by adopting the colors for this particular color space that is mentioned in output intent.

For more detailed information I would recommend you to get knowledge about the PDF/X standart and concepts around it.