Need help with an X-rite experiment?!

Hi everyone,

I use an X-rite 939, and so do our various print vendors. Over a year ago, my company's major client had a color complaint on a printed piece, stating that it was over "a half a shade" off from their Pantone® books. I then delved into figuring out what "a half a shade" meant to them. Long story short, my company and our print vendors are solely using L*a*b* values now, with a maximum deviation of 2.0 DEcmc (with some exceptions) via X-rite. Nowadays, when our #1 client has a problem, we show them the numbers, and remind them that they agreed to the science of the 2.0 tolerance.

For the most part, all was well, although our printers have difficulty with some colors (the DeltaE might be like 3.5, but visually you can't see any difference, or PMS 285 was finally perfected by using different 'imitation' ink bases, for example). But then THIS happened...

Customer rejects job based on color. It should be PMS 267C but it doesn't look like it, they say. Because I keep samples of all litho labels until a week after the ship date to the customer, I pulled the samples and shot 'em. The print vendor was getting numbers between 0.45 and 1.30. I was shooting numbers from 0.60 to 1.11. So we were both in the ballpark. Then I pull out the Pantone book, and YIKES!!!!!! WOW was that color different! I shot five, count 'em, FIVE Pantone books (four coated and one color bridge), two of which were opened for the very first time. One was the book from the client. The numbers were coming up around 1.7, 1.9 etc... I've shot PMS books before and usually they're well under 1.0 in their L*a*b* values. In addition to PMS 267 being pretty off in the book, it was also off to the Red/Blue side. Our 0.60 labels were slightly to the Yellow/Green side, but pretty much on the mark. So actually, the colors appeared to be off by close to 3 DEcmc, because they were on opposite ends of the color spectrum.

(Bored with this yet?)

The solution, of course, is if they like the color that's in their Pantone book, we take the L*a*b* numbers from THAT and create a custom color based on the numbers. But I foresee a WHOLE bunch of hassles down the road with this idea. Not sure yet how this is all going to pan out.

AND NOW FOR THE EXPERIMENT:

I'm curious if YOUR Pantone 267C in your book is way off from the actual LAB values. According to our X-rite QA-Master II v 8.2.1 software with the stock Pantone 2005 C library, the values should be: L*=30.30 a*=35.52 b*=(-52.44) and C*=63.33 h*=304.11. We set it up as DEcmc, l:c 2.00/1.00, commercial factor 1.0. Illuminant/Obs. 65/10.

Would you please shoot 'em for me using the same settings above and report your results? I'm anxious to find out if Pantone pulled a boner on that color, or if X-rite had the LAB numbers wrong or something.

Thanks in advance for your help !

 

Photoshop CS4 shows CIELab D50/2 = 27, 40, -56 for PMS 267C. A recent PANTONE Formula Guide shows 26.78 42.87 -56.39 when meaured on black backing and 26.86 42.98 -56.22 when measured on white backing. A 1991 book shows 28.97 38.76 -52.84 for the same PMS 267C swatch. Quite a distance, visually. I'm curious why you're using D65/10 for graphic arts? I think this is the wrong standard and may partly explain your problem.

 

Hello, ive used these machines to a tolerance of delta E 1 The substrate has big role in changing the readings, also if the pms panels have been touched by fingers this also changes the readings If the customr has taken average readings this will mess up any readings, also different x rite machines give different readings I have found that the only true way of keeping a colour to tolerance is to measure an on press version of the colour the customer wants and store it.

 

Was the job printed in pms 267 aquoes coated laminated or cured in any way as this may have an effect on the phenels in the pigment. As a rule we always use light-fast or chemicaly stable inks when running any colour that has reflex, 072, purple or violet in the mix.

Hope this info was of some help
Gazman