'Pantone Colour/CMYK/etc Matching For Idiots' advice, please..?

[David Ingram]

Wow this is a great question! and you've already got some great advice. I think Padzilla is right on when he says the (Bridge) book is the best one to use. The one with the ACTUAL PMS and the Pantone FACTORY BUILD (CMYK +other colors lab, rgb) is the way to go. The reason the colors differ is that special pigments are used in the pantone inks that are NOT in CMYK, take reflex blue for example. The pigment that gives reflex it's "SNAP" isn't possible with CMYK inks. Invariably, because office color printers and inkjets are optimized for RGB, they produce a "Corporate Blue" very easily, when converted to CMYK though, PMS colors in the dark blue ranges almost all, tend to go too purple.

RELY ON THE BOOK! (values) when converting to CMYK, the CMYK shows you what is going to happen on paper at least, also realize that some workflow systems (I.e. prinergy might use their OWN lookup table for colors) in addition to the different ones in say Quark, Illustrator and photoshop. I use the pantone SOLID coated builds when going to spot color, regardless of stock. (they seem to me more accurate than the uncoated colors), and PRE CONVERT any PMS BUILDS to BOOK VALUES (bridge) before sending postscript to imaging. Meaning postscript for 4 color, goes to the rip four color and the rip is not deciding anything with regard to conversion of the spot colors. Remember, if you rely on a 6 or 8 color inkjet, and you're only using CMYK on press, the chance of you hitting that perfect half shade like the inkjet can is, pretty remote. From what i'm told Hexachrome is less than 5% of the market STILL and Stochastic/FM/AM/Crystal Raster, Staccato, is even harder to push up or down as far as conventional CMYK (non stochastic) like the adjustment range on that is less than conventional.

Have a question, show your client the bridge book, if they're corporate, they'll almost always OPT for a 5-6 color job (CMYK + PMS) over CMYK alone with "approximated" colors.

[jstanzione]

I have read through the thread on this, and wanted to add some additional information.

PANTONE COLOR BRIDGE COATED was launched in April 2005, and was a direct replacement for the PANTONE solid to process guide coated, circa 2000. PANTONE COLOR BRIDGE represented a complete re-engineering of the product, which produced a completely new set of CMYK simulation values.

Within the Adobe Creative Suite 3 applications, you will find a specific library named as PANTONE COLOR BRIDGE CMYK PC. This library is produced in CMYK color space, and uses explicit CMYK data provided to Adobe by Pantone. If you are using PANTONE COLOR BRIDGE COATED, you must select your colors from the PANTONE COLOR BRIDGE CMYK PC library, in order for your CMYK values to be consistent with the Guide. If colors are selected from the PANTONE SOLID color libraries, and 'converted' to CMYK, you are using Adobe's internal algorithms to make the conversion, and your values will not be consistent to the Guide, or necessarily within the various CS applications.

If you are using an earlier version of Adobe Creative Suite, there is an installer available free of charge to load the PANTONE COLOR BRIDGE libraries. Please contact Pantone directly for details on how to obtain the installer.

Best regards,

John Stanzione
Manager - Technical Support
Pantone, Inc.

Support Web site: http://www.askpantone.com

[jardo]

Does anyone have a preferred application for the conversion of a Pantone (Lab) color to CMYK? Is there any program, other than Photoshop, Illustrator, Indesign, out there that can do a better conversion? This is assuming that you have a Pantone or Lab color that you want to reproduce and a good working ICC profile to feed the program? I would especially be interested in all the Pantone colors that you can not hit that are out of gamut, but have this program come the closest match in CMYK without constantly color correcting till someone visually and subjectively says, "We can not get any closer." Thanks.

[Thierry]

One more precision after the reply of John Stanzione: if you are european or working for the european market, use the Color Bridge CMYK EC (and not PC)! This one is also available in Adobe's apps (and in the Pantone surival kit) and is intended to work with european inks. The translations in CMYK will be far more accurate especially for some difficult colors like deep saturated blues.

[kaljh]

I am so frustrated with trying to match cmyk to Pantone. If the bridge is a more updated version of the solid Pantone to process guide, then why are the colors so different. For example, solid Pantone 167 is WAY different from Bridge 167. If we can't even count on the 2 book colors being the same, how do we know which cmyk breakdown to go by?

What good is updating the system when the initial colors are so different to start with? Shouldn't pantone 167 be the same color in both books? I thought the conversion values were different because the bridge was supposed to be more accurate. But all it's doing is giving me a whole different color!

Instead of making things better, Pantone just made everything more confusing. And now they're adding Goe to the mess. If us printing folk can't get a handle on all this color confusion, how are our clients supposed to understand this? Am I just missing something here?

[Lukas Engqvist]

Pantone is the colour in the Bucket. It can vary on substrate quite significantly. Pantone is a recipie for mixing colors, but if you want to describe an actual colour use a Spectrophotometer like the xRite munkey (unsure of spelling) measure your patch and write the Lab values. Then convert to the CMYK values of your output proccess.
Pantone did not intentionally make things complex. Reality is complex and they are trying to make it simpler. You can't blame chemistry for not being simple. The problem arises if we start teaching things we don't understand, then we'll end up with some variant of chinese wispers (a childrens game where you wisper information and see what you end up with after a certain numper of itterations).

The question must surely be what colour I will percieve on paper and any CMYK values in any application must be of secondary importance. The destination rather than the road?

[juergenroesch]

Printing Pantone is very simple: buy the bucket with the respective ink from Pantone and define it as a 5th color in your layout and if you print on exactly the same paper as the Pantone color guide and leave it in the drawer for about the same amount in months (so the ink can dry back) it might just look the same.

If you print on Coated, Uncoated or Matte paper, you just pull out the respective guide, but you only need to buy one bucket of ink as they refer to just the same inks.

Already if you print tints, things can become more complicated as each print process has its own halftone behavior. Sheetfed, web, gravure, flexo ... - and that's BEFORE you try to emulate them on a CMYK process.

Once you try to bridge the gap to CMYK things can really turn ugly and even more so if you try to establish a common CMYK standard value for international printing. This simply is not possible - you can't provide a single CMYK value which will look identical no matter where and how it is printed, so why risk it?

You can make suggestions, but these CMYK guide values are to be understood as guidelines - not as absolute references. And if you do so you have to specify the print standard to which these references actually apply. Like the PC or EC version of the Bridge guides.

Especially in packaging companies go a different route by publishing ink drawdowns and step wedges of their corporate colors with Lab values and tolerance values. Even there things can be tricky, so one big packaging customer even specifies what measurement device to use, and what measurement geometry settings on this device - and yes - you have to send your device annually in to the manufacturer of your device to get it recalibrated. But using these strict guidelines helps this company to achieve very accurate color matching on a world wide basis. Their color cards even have an expiration date, which takes into account the fading of the ink and they must not be used any longer after that date.

This way design and print companies working with this client can specify their own recipes to match these colors and these recipes can also vary depending on what substrate gets printed on. As this is a packaging customer, these colors usually get not split into CMYK, but substrates vary from plastic labels to corrugated cardboard.

If you look closely you see the difference:
- Pantone is selling you fixed recipe ink buckets and gives you a couple of different guides which give you an idea of how this particular ink can print on a select variety of papers (like Coated, Uncoated, Matte). If your paper differs, expect variations
- this packaging customer is specifying on the other hand the visual appearance of their corporate colors and it is up to the printer to mix the ink properly to get on what ever substrate is to be used an accurate match (they have already an ink supplier and base recipes for many common print materials, so it usually is only a mild change in the recipe to be used locally)

So it is inks versus visuals.

Many designers mix this up and understand Pantone colors actually as visual references instead of ink recipes.

Also as pointed out several Pantone colors are not achievable in most CMYK print processes. Those are not the majority, but usually these are the ones designers like to pick as they stand out.

Lukas on the other hand quoted a very important reason to even use Pantone colors which are in gamut: to avoid screening. As a designer with an inkjet based digital proofer the difference might not be clear, but if you use as a background tint some camouflage style brownish colour and want a 10pt white text on it, it can look great on your proofer, but turns unreadable on press, because that colour likely is a screened pattern made up of all 4 channels and the white text just disappears in the dots. Print the same as a solid spot and your text is crisp and sharp.

The best way to specify corporate color appearances is to get solids printed along with step wedges on cards that get labeled with the color name like "CustomerXYZ-Red" and "CustomerXYZ-Blue". Note the Lab value you would like to see next to the solid and specify measuring geometry (like D50 2degree 0/45 and "no filter") and an expiration date of maximum 3 years (if the sample is kept protected from light in a folder). By using a custom color name you avoid that your local printer will pull his whatever version of Pantone book (maybe one from 1996 - see the print on the back or spine of it) and matches your Pantone color name to his book - which might look markedly different to the one you used when you specified that color. Especially if the books are of different years and for different markets (America, Europe, ...)

[rab]

One thing I'd like to add. The reason photoshop's build is so different from Illy MAY be because you are picking the Pantone coated library in Photoshop, Photoshop then converts this spot colour using whatever profile you're using in your working space. If you want closer correlation with Illy's book values use the Pantone process instead as these values are already CMYK and are not converted with a profile.

[Lukas Engqvist]

Thank you for taking the time for an eloquent comprehensive response.

[Werby]

Originally Posted by rab

The reason photoshop's build is so different from Illy MAY be because you are picking the Pantone coated library in Photoshop, Photoshop then converts this spot colour using whatever profile you're using in your working space. If you want closer correlation with Illy's book values use the Pantone process instead as these values are already CMYK and are not converted with a profile.

Yeah, but why do Photoshop, Illustrator & InDesign have different LAB values for Pantone colors? Of course you are not going to get the same CMYK values if you start from different LAB numbers. Can ANYONE tell me why these programs all use different LAB values??

Here's an example: Pantone Solid Coated library, 363 C
Photoshop CS3: L=51, a=-39, b=39
Illustrator CS3: L=53, a=-40, b=43
InDesign CS3: L=53, a=-47, b=46
Also, my inkjet RIP has built in look-up tables (apparently licensed from Pantone), and this is what it says:
L=50, a=-42, b=42

OK, wow, that's a lot of delta-E! Which one is right?

-Todd Shirley