Change multiple color definitions to same pantone?

Question

I am using FM10, I need to change a few unque color definitions to the same pantone color, I was successful with the first one but got system messages about not being able to define more colors to that same pantone. I understand this is a program rule, but I am wondering if there is a way around it because I still need to define those other colors as the same pantone. I tried a work around that failed - defining the same properties of the pantone I wish to use with regard to cmyb values but the color was not the same as the coated pantone I was trying to emulate, is there a trick I am missing here? Thanks for any help you may provide.

Answer 1

Disclaimer: I don't work in managed or CMYK color. We leave (sRGB) color in, but print in B&W bitmap.
I suspect that the thing that provides end-to-end color control with the Library colors is that they encode a <ColorLibraryInkName ...> which is passed into the PostScript output and also into any PDF output. The print shop or Pantone-aware RIP can see this name(tag), and knows how to render it. The encoded CMYK is probably ignored in that case (and may not match the initial Library settings in any case).
The actual CMYK values in the PS and PDF are usually trashed by the Windows GDI, which despite the fake CMYK available in Vista SP1 and later, is still an RGB engine.
If you save a document as a MIF, you can see the encodings using a plaintext editor.
In the <ColorCatalog section of a test MIF, a typical Pantone looks like:
<Color
  <ColorTag `PANTONE 3308 CVC'>
  <ColorCyan  99.998474>
  <ColorMagenta  0.000000>
  <ColorYellow  59.999084>
  <ColorBlack  71.998596>
  <ColorLibraryFamilyName `PANTONE\xa8  Coated'>
  <ColorLibraryInkName `PANTONE 3308 CVC'>
> # end of Color
Now suppose we create what we think is the same CMYK color:
<Color
  <ColorTag `CMYK-100-0-60-72'>
  <ColorCyan  100.000000>
  <ColorMagenta  0.000000>
  <ColorYellow  60.000000>
  <ColorBlack  72.000000>
> # end of Color
Notice two things:
No name. The print shop (or Pantone-aware print engine) has only the who-knows-what CMYK values to work with.
The initial CMYK values aren't even the same, although they look identical in the Color Definitions dialog. And they will be even more different in the PS and PDF on the Windows platform.
There could be easily be a more elegant way to fix this, but for a single file, a simple MIF hack would be:
Make sure the named Pantone color is in the Color Catalog.
Find, in the <ColorCatalog, each custom color that needs to be redefined.
Delete it, from and including <Color to and including > # end of Color.
Batch replace all other occurances of that custom color with the Pantone.
Using the examples above, change all
<FColor `CMYK-100-0-60-72'>
to
<FColor `PANTONE 3308 CVC'>
Repeat the above for each custom color.
Save the MIF and re-open in Frame.
Another way to get all your CMYK content under a measure of color control is to do ALL the color content as imported EPS. Mr.Bill's GDI shredder passes it through unscathed. This means no Frame art and color text only with great annoyance.