Pantone books in CS5 vs Pantone Plus books in CC

Question

Hi All,
After a recent upgrade from CS5 to Creative Cloud, I created a new graphic using our corporate Pantone Colour (PMS 541u), but when I sent it to (digital) printing, I discovered that it did not print the colour we were expecting.
I understand that the new Pantone Plus books no longer have CMYK values attached to the PMS colours, instead they only use LAB colours, so rather than the old way of printing using the CMYK values linked to the spot colour chosen, it now converts the Spot colour to a LAB colour, then to a CMYK colour that is completely different to the CMYK values linked to the 'old' PMS colours.
Given that it is imperative for us to ensure that our  corporate colours reproduce as close to the colours on our packaging (there are 20 different products that are printed in true spot PMS colours), this makes it very difficult to match colours now.
I have tried using the new 'colour bridge' colours, but again, they're completely different to the old PMS colours and the new Plus colours. We use both coated and uncoated stock, so we need both the 'u' and 'c' CMYK values depending on what stock we're printing on.
here is an example of the variation in colour (PMS 541) that i'm experiencing, both on screen (yes I know it's not an accurate representation), and when printing digitally.
I don't particularly want to remove the new colour books and replace them with the old ones as is suggested in a few work arounds, as I want to ensure that we're using the most up to date colour profiles/books etc.
Can someone please explain what is the best way to achieve an accurate colour match when converting from PMS to CMYK for process printing?

Answer 1

I'd say that the answer to your final question isn't to use the old colour books. In fact, the newer, LAB-based ones will yield a better match if your settings are right.
Firstly, get your Colour Management settings right for the output conditions, by using an appropriate CMYK profile (I can't tell you which one this would be without knowing how you're printing). This way, if you convert your spot swatches to process in Illustrator, you should automatically get the closest match.
Also, you say digital printing. Many RIPs for digital presses and copiers have built-in spot colour simulation libraries, which you can manually adjust to the closest match possible. On Fiery RIPs (which I'm most familiar with), this feature is called 'Spot-On'. If you send the job to the printer with spot colour swatches intact, and named as they normally are, the RIP will convert them to the specified CMYK formulas.