CS6 PMS Values in CMYK vs CS5 PMS Values in CMYK

[billw@mlode.com]

Greetings,

I have seen similar, but no exactly the same, queries. Example, CMYK value for PMS 2587;
In CS5 they were c=59%, m=66%, yandk=0%
In CS6 2587 they are C=57.64%, m=83.15% yandk=0% when color settings is Prepress2
In CS6 change color settings to Emulate IL v6 and 2587 is now c=62.34%, m=73.91%, y=1.88%, k=0.26.

The fact that the color looks different on screen when opening a IL5 file that has PMS 2587 in CS6 compared to creating a new element in CS6 with PMS 2587, is somewhat concerning. But what could really cause a problem is if we created a new PMS 2587 item in CS6, converted it to CMYK and then expected it to match on press what we printed using a CS5 conversion in the past.

I realize that the solid coated library is now Pantone + and based on Lab values, a good thing. Other than changing the CMYK values after conversion to the CS5 values is there anyway to fix this potential "landmine" waiting to be stepped on at press.

[gordo]

Other than changing the CMYK values after conversion to the CS5 values is there anyway to fix this potential "landmine" waiting to be stepped on at press.

Become Pantone Certified? 8-P

(apologies. I couldn't resist)

Best, gordo

[leonardr]

I guess I am confused.

If you are working with Pantone colors, then you are doing so because you plan to actually print that specific ink. In which case, you don't care about the CMYK values.

If you are planning on printing entirely in CMYK (process), then why are you authoring with a Pantone?!?!!?

[chevalier]

The Pantone+ series made a "clean" break from the traditional Pantone series. CS6 is the first suite to get the Pantone+ built in. A lot of this change seems to have started with X-Rite bought Pantone. I wish they'd dump the thing and force everybody to use Goe.

Pantone does not give out information as to what the basis of these conversions is. It has been a major headache for us in packaging. I really wish they would just assign CIELAB addresses for their color system but I think financial motivations keep that from happening.

[chevalier]

I guess I am confused.

If you are working with Pantone colors, then you are doing so because you plan to actually print that specific ink. In which case, you don't care about the CMYK values.

If you are planning on printing entirely in CMYK (process), then why are you authoring with a Pantone?!?!!?

Because that is what graphic designers do. They design a document with 25 pantone inks and expect it to print on a 5 color press. It's a never ending headache in prepress.

[billw@mlode.com]

Because that is what graphic designers do. They design a document with 25 pantone inks and expect it to print on a 5 color press. It's a never ending headache in prepress.

More times than anyone would imagine!! Along with designing labels in Quark and InDesign, or sending what one thinks is a "print ready" PDF file.

[FlexoGrunt]

More times than anyone would imagine!! Along with designing labels in Quark and InDesign, or sending what one thinks is a "print ready" PDF file.

Or the people that send you a JPG and expect it to cost nothing on the prep side and print as 5 sport colors.

[David Milisock]

It may be that Adobe has now adopted the new LAB specification for converting to CMYK. This is a serious issue for the wide and grand format departments of printing companies.

[rich apollo]

I guess I am confused.

If you are working with Pantone colors, then you are doing so because you plan to actually print that specific ink. In which case, you don't care about the CMYK values.

If you are planning on printing entirely in CMYK (process), then why are you authoring with a Pantone?!?!!?

Leonard, it's common practice to use the Pantone libraries when laying out documents. It gives designers access to a large, pre-formulated pallet and the designers usually have no foreknowledge of how something will be produced. By using Pantone colors, the files can be more easily broken out into the appropriate separations.

Have the L*a*b* values changed? If you set Illustrator to use "Standard Lab values" and then do your own conversion to CMYK, how do the values fare?

The pre-baked CMYK values are problematic at best. Having the software packages default to the L*a*b* definitions of colors would go a long way toward removing this issue.

[Stephen Marsh]

It is mostly about source and destination. What is the exact Pantone library source? Is it L*a*b* based? Is it a hard-coded CMYK Bridge library etc? What about the destination? Will the final CMYK values be directly generated from the source table (Bridge CMYK) - or will the CMYK values be generated by the destination CMYK profile, CMM and Rendering Intent set in your Adobe Colour Settings from a L*a*b* based Pantone library?

I agree with Rich that the "historical standard" of selecting hard coded CMYK values for Pantone colours has never been ideal. All it did was perpetuate the fallacy that there were device independent CMYK values, when CMYK values are patently device dependent. This has lead to many colour reproduction problems with designers thinking that these CMYK based Pantone library colours were a fixed colour standard. If the end user uses a L*a*b* based library and has a good CMYK device profile describing their final print condition, then the colour match should be a lot better between the spot source and the process destination simulation.


Stephen Marsh