http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=325905
Issue
Pantone color values set in Adobe InDesign or Adobe Illustrator appear to be different colors in Adobe Photoshop.
Solution
Set the applications to use the Lab values in the library.
In InDesign:
- Open the Swatch palette and select Ink Manager from the palette menu.
- Select “Use standard Lab values for spots”.
- Re-create the spot color.
In Illustrator:
- Open the Swatch palette and select Spot Colors in the palette menu.
- Select “Use Lab values”.
- Re-import the spot color.
Additional Information
You must set InDesign CS3 and CS2 and Illustrator CS3 and CS2 to use Lab values that are in the library; this is not the default setting for either application. When you set InDesign CS3 and CS2 and Illustrator CS3 and CS2 to use the Lab values, you can encode alternate colors for spot colors using the same Lab values. If spot colors are converted to process colors, then Illustrator CS3 and CS2 and InDesign CS3 and CS2 convert those Lab values to CMYK using the Profile selected at print time or using the document profile if the conversion-to process happens before print.
There is no setting to use Lab values in Illustrator or InDesign in versions earlier than CS2. Neither application used different Lab Pantone values; both were designed to use the Pantone CMYK values to define color appearance, while Photoshop uses Lab. This was changed In InDesign and Illustrator CS2.
330728: CMYK values of PANTONE swatches are different in Illustrator CS and Photoshop CS
PANTONE swatch overview
The PANTONE Matching System (PMS) is the dominant spot color printing system in the United States. Printers use a special mix of ink to achieve the color needed. Each spot color in the PANTONE system is assigned a name or a number. There are over one thousand PANTONE spot colors available.
Are PANTONE 624 U, PANTONE 624 C, PANTONE 624 M the same color? Yes and No. While PANTONE 624 is the same ink formula (a shade of green), the letters that follow it represent the apparent color of that ink mix when printed on different types of paper.
The letter suffixes of U, C, and M tell you how that particular color will appear on uncoated, coated, and matte finish papers, respectively. The coating and finish of the paper affects the apparent color of the printed ink even though each lettered version uses the same formula.
In Illustrator, 624 U, 624 C, and 624 M look exactly the same and have the same CMYK percentages applied to them. The only way to truly tell the difference between these colors is to look at an actual PANTONE swatch book.
PANTONE swatch books (printed samples of ink) come in uncoated, coated, and matte finishes. You can use these swatch books or color guides to see what the actual spot color looks like on the different finished papers.
PANTONE swatches in Illustrator CS
The PANTONE swatch libraries that reside in Illustrator CS contain CMYK representations of what the PANTONE ink will look like when printed using a spot color plate. The CMYK values were given to Adobe by PANTONE and are stored within the PANTONE swatch. When these swatches are converted to CMYK colors, or printed as process colors, the CMYK representations inside the PANTONE swatch are used. For instance, if you take an object with PANTONE 2905 C applied to it (which has a CMYK representation of C=41/M=2/Y=0/K=0), and run the Filter > Colors > Convert to CMYK command on the object, the object will have the values of C=41/M=2/Y=0/K=0.
PANTONE swatches in Illustrator CS3, CS2
The PANTONE swatch libraries that reside in Illustrator CS3 and CS2 have both LAB and CMYK representations of what the PANTONE ink will look like when printed using a spot color plate. Both the LAB and CMYK values were given to Adobe by PANTONE and are stored within the PANTONE swatch. Illustrator CS3 and CS2 gives you the ability to choose either the LAB color definitions or the CMYK color definitions when using PANTONE libraries. You can choose which color definition you want to use by selecting Spot Colors from the Swatches palette menu and then choosing the desired color definition.
The CMYK color definitions are the same as those in Illustrator CS and convert to a process color within the application or print from the application as process colors the same way they do in Illustrator CS.
The LAB color definitions in Illustrator CS3 and CS2 mirror the LAB color definitions in Photoshop CS, CS2 and CS3. While Illustrator does not have full LAB support as a document color space, it still can use LAB color definitions by using the Adobe Color Engine for color conversions to CMYK values. If these swatches are converted to CMYK values, the CMYK values vary depending on either the ICC profile assigned to the document, if the swatch is converted within the document, or on the printer ICC profile, if the document is printed.
http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=330728
PANTONE swatches in Photoshop CS, CS2 and CS3.
The PANTONE swatch libraries that reside in Photoshop use LAB representations of what the PANTONE ink will look like when printed using a spot color plate. When you apply the swatches to objects or duotones in Photoshop, Photoshop displays the color using the LAB color definitions. If these swatches are converted to CMYK values when printed, the CMYK values vary depending on the ICC profile you chose in the print dialog box.
How to match Illustrator PANTONE swatches to Photoshop
For Illustrator CS3 and CS2:
In Illustrator CS3 and CS2, you can match the PANTONE swatches to Photoshop CS, CS2 and CS3 versions of the swatches by selecting the “Use LAB Values specified by the book manufacturer” option in the Spot Colors option dialog box. To access the Spot Colors dialog box, select Spot Colors from the Swatches palette menu.
For Illustrator CS:
In Illustrator CS, there is no way to automatically match the Illustrator PANTONE swatches to the swatches in Photoshop. The Illustrator swatches use specific CMYK color definitions provided by PANTONE, and the Photoshop swatches use specific LAB definitions.
How to match Photoshop PANTONE swatches to Illustrator
For Illustrator CS3 and CS2:
If you are using the CMYK color definitions for PANTONE swatches in Illustrator, you can match PANTONE swatches in Photoshop to the ones in Illustrator by using the swatches from the PANTONE Solid To Process library in Photoshop. These swatches are designed to use PANTONE CMYK values.
If you are using the LAB color definitions for PANTONE swatches in Illustrator, you can match the PANTONE libraries in Photoshop by using any of the default PANTONE libraries, as they use the LAB color definitions as well.
For Illustrator CS:
You can match PANTONE swatches in Photoshop to the PANTONE swatches in Illustrator by using the swatches from the PANTONE Solid To Process library in Photoshop. These swatches are designed so that they use PANTONE CMYK values. The swatches in this library do not go through the LAB to CMYK conversion like the other PANTONE libraries, so they match the PANTONE swatches used in Illustrator.
