Thanks Rob. The question was: why do I get 3 different cmyk values under the same colorspace (Europe, prepress 3) from PS, AI and ID for the same Pantone colour?
I'm not seeing that with the Pantone + Solid Libraries when the solid spot colors are Lab.
Make sure InDesign and Illustrator are set to define spots as Lab (in Photoshop solid libraries are always Lab). In ID it's under Ink Manager. In AI it's Spot Colors... under the Swatches flyout.
Also make sure the document CMYK assignments (Edit>Assign Profiles) are Europe Prepress 3 before you convert the swatch to CMYK. It's the assigned color profile not Color Setting's Working CMYK profile that makes the conversion, so simply syncing your color settings might not work.
Pantone can't print conversions for every printing condition on their swatches so their CMYK values are somewhat arbitrary—they would have to be for one specific condition.
If you don't want color managed conversions use the Pantone + Color Bridge libraries, which are set CMYK builds.
Here's what I get for Pantone Cool Gray 10 solid conversions in the 3 apps when US Sheetfed is the assignment:
Message was edited by: Rob Day