Please forgive this rather lengthy post.
I am not creating these files. I work in prepress and I am receiving these files from clients. The Pantone 364 conversion is just one example. David, that’s exactly what we end up doing. Creating a custom CMYK swatch.
But this can really becomes a nightmare when there are several parts to a project that are supplied over time. Once colors are manually tweaked for a better match care must be taken to use the same values on subsequent jobs; when a client resupplies a whole new file; when the job comes back six months or a year later, etc. etc.
We have ten operators processing sometimes hundreds of jobs a week from thousands of clients outputting to several different devices. The new method of using LAB to convert is supposed to give better results. I have not seen better results. A couple times a week we DO create a custom CMYK color swatch because the Lab converted result is lousy. Quite often this isn’t recognized until after a hard proof has been produced.
I am looking for a way to get better color right out of the gate when clients supply files with Pantone spot colors that will need to be converted to process. (And many of these clients are handing us PDFX1A pdfs that used this LAB method to convert the spot colors in their jobs BEFORE they give it to us. They unknowingly end up with less than the optimum results.)
Am I missing something in the workflow that would produce better results? I am trying to get this LAB conversion to work the way it seems it is supposed to work. Or is only supposed to work in conjunction with a sophisticated RIP that does the conversion? Maybe Adobe’s intention is for the file to be handed to the RIP with the spot colors in tact; to let the RIP do the conversion? But why can’t Adobe software produce the same conversion that the RIPs do? What if a client supplies one pdf that they converted in InDesign and another with unconverted spot colors that we let the RIP convert. The color of the two pieces will not match.
THIS IS WHAT I SEE IN ADOBE ILLUSTRATOR:
The tool description when you select Use Lab values in Spot Color Options in Illustrator reads: “Use this to get the best possible match to the actual spot ink when spot colors are converted to process as part of a color-calibrated workflow”. I get the same conversion no matter what color working space I have selected.
In addition, in Illustrator, under Spot Color options there is an alternative radio button that can be selected that reads: “Use CMYK values from the manufacturer’s process book.” When this option is selected no change takes place in the way spots are converted. Illustrator still appears to be using the Lab method. (Oh! Wait! Maybe Illustrator is trying to tell the operator to pick up a swatch book and type in the CMYK values that appear in the swatch book. Are these two radio buttons under Spot Color options just informational?)
In my dream world all graphic designers use the TRUmatch system for 4-c jobs. (BTW, thank you, InDesignSecrets, for my shiny new TruMatch swatch book.)
