27 colors limit in Acrobat 9 Output Preview tool?

[Dov Isaacs]

As much as it is easy to make fun of use of so many spot colors in a document, there are valid use cases for this and workflows that readily accommodate same.

An Adobe customer showed me an example of such a file a few years ago at Graph Expo. It was a marketing piece in which each NFL team's football helmet was shown on a single page. These helmets had particular Pantone spot colors associated with them. In total, several dozen spot colors ended up in the document. Obviously, they were not planning on printing on a press that had that many spot colors or doing multiple passes to get that many spot colors. What they were planning on doing was using six process colors (such as CMYKOG) with a RIP that supported n-colorant ICC color profiles that could convert the LAB representation of those spot colors into reasonably good approximations using the six available process colorants.

I suspect that you will be seeing more of this in the future as some of the very high end digital printers start adding support for five, six, or more colorants. This is a very reasonable and valid workflow!

- Dov

[kyle]

Dov:

Fair point, but in that case, I think it would be better for the colors to be defined as CIELAB. That would be less ambiguous and would allow the creation of a PDF file with colors converted to the destination space or preserved as CIELAB. Either way, the PDF would not be crippled by a bunch of extra inks that should not print, and would generally allow easier preflighting. I'm guessing that the pages would also draw faster with output preview turned on.

[Dov Isaacs]

Problem is that CIELAB is not a color space that is typically accessible in most programs (including Illustrator and InDesign). You can place PDF content with it and you can use spot colors defined in CIELAB, but forget about using it as the program's editing color space. Also, much art work is pre-supplied with Pantone colors. And for that matter, it isn't always that easy to manually determine the LAB alternate colors for such spot colors.

- Dov

[kyle]

Dov:

Indesign appears to work with lab colors equally well as spots for native elements, with one exception: you can't tell it to convert lab to spot when exporting to PDF but you can convert spot to lab if that is the alternate color space. If you use spots that are defined in lab, then the document can be output either with spot inks defined in lab, or with lab colors if spots are converted to process with the ink manager and no color conversion is applied. Illustrator is definitely more lacking, though it is still possible. If you create lab defined spot swatches in Illustrator, then place the Illustrator file in Indesign, it can then be output as lab color. You can also output native lab elements from Illustrator by printing and converting to process, but unfortunately that doesn't work when saving to AI/PDF - you have to use Indesign as an intermediary to preserve transparency and other non-postscript properties.

I would expect that most documents that have 16 spot colors to be printed in CMYK (for legitimate reasons) would be done in Indesign anyway, because they are probably layouts that have multiple logos, not individual graphics. If someone wants to trust Indesign's Pantone lab values (since they probably came from Pantone), they can change the spot inks to be defined as lab, and Indesign will use its own lab values, overriding any definitions in placed graphics as long as the ink names match up with its library. They can then export a PDF from Indesign with the spots set to convert to process in the ink manager, and either convert everything to the destination space if they know it (which would convert the spots based on Indesign's lab definition), or perform no conversion which would leave the elements defined as lab in the PDF.

[zoran]

I saw a job once for Disney that had 13 inks actually being printed. Whats the most you've printed?

Can not remember the most ever, but we often max out our 102 CD and all 10 units with stamps.