This is part of a series about my experiences in publishing a book.The series starts here.
In my last post, I reported on my worries that the captions and footers weren’t sufficiently legible in the Matchprint proofs. I finished reviewing the proofs, and dropped them by Jerry’s offices today. We talked about the captions.
I suggested that they be made darker. He thought that they should be darker than they looked in the Matchprint. We then suspected that the Matchprint wasn’t doing a good job of matching the spot color on the printed page.
Jerry pulled out a Pantone swatch. We compared it to the Matchprint. It was darker than the Matchprint.
Then we pulled out the press proofs. There was a large swath of the spot color there. We compared it to the Pantone swatch. They matched. So the Matchprint was off. And not just a little.
I think the captions are going to be just fine.
Dan V. says
Matchprints, nobody uses those anymore. Kodak discontinued the material as they were something done with film separations. Kodak HAVE, however, taken that old brand name of what used to be donor material on vacuum tables and started using it on Epson proofs on Kodak Matchprint brand paper. I’m not ragging on you at all Jim, I’ve always been amused at Kodak’s transplanting of the name of a specific old process type on to modern Epsons.
For some context… Unless you’re shelling out for an actual dot proof (the last of which is the Fuji Finalproof, though there are still a few, rare Kodak Approvals or Creo Spectrums out there, which run on a process similar to the Finalproof and are not old-style matchprints) the vast majority of contract proofs these days are done on Epsons or other inkjet printers. Depending on the model of printer and how it is driven, you can get a wildly different interpretation of the spot color. But dot proofers had a flaw in that while they were great for reproducing how actual CMYK behaves on paper, they often run too clean and without special donor rolls for spot colors you were simulating spots to CMYK only and this was suboptimal because of limited gamut. On the other hand, you could legitimately proof a real spot color… if you had the roll of donor material.
Next, workflows can work against you if you don’t know the knee-deep details of how the printer is proofing. Some printers have pay-for options to direct-drive proofers from their workflows (Prinergy, XMF, Rampage, Prinect) which have certain limitations depending on how they are set up. Users of those workflows may also choose to export out files (which may or may not contain native spot data!) to a third party color management and proof driver engine such as Oris ColorTuner or EFI Colorproof, which has their own built-in lookup tables for spots in LAB format to try to get as close to the spot as possible. Kodak Matchprint is similar to ColorTuner.
Based on your posts of your book printer, they’re using an Epson 9900 on Kodak Prinergy with the Kodak Matchprint proof software. I’m assuming that they’re doing LAB spot color lookup which I believe the Matchprint software does. This method will try to find the closest color in the gamut of the printer itself, versus the G7 standard that the press uses for CMYK gamut. This, currently, is the best method to look up spots for an inkjet and all the major workflows can do it this way if the customer desires. The 9900 has a pretty wide gamut thanks to the orange and green inks and can reproduce many spot colors correctly, but it can have trouble with spot tints and certain colors. Since you didn’t mention what PMS color you’re using I can’t say how close to the gamut of usual 9900s it would fall under, but in many cases printers are using relative colorimetric mode by default and will clip the color to the closest one in the gamut. Odds are this is what happened to your spot color and why it looks a little lighter. The only way to truly proof a spot color is to run it with the actual ink (either on press or a dot proofer) because those spot inks are made with pigments that often have different spectral properties than ink in an inkjet printer. Modern inkjets (especially the new P7000/9000 with the violet cartridge in place of LLK) can get amazingly close, but they are still not perfect. I will reiterate that the one true reference for spots is the printed swatch in the Pantone book. As good as the proofers are, they cannot be 100% the same.
Pantone also repeatedly tweaks their LAB formulations for reasons that nobody explains, and depending on which definition gets pulled (the one in the PDF document, the one in the workflow’s spot library, or the one in the proofing software’s library) you may get slight differences.
FWIW, I worked in development for a small company that wrote a major workflow software for the printing industry (and was gobbled up by a much larger company where I still work today).
Thanks for the details.
As I said here: http://blog.kasson.com/?p=15475
Dan V. says
Such as it is for reading things in reverse chronological order. 🙂 Hadn’t checked up your blog in a while so I was trying to catch up.
I appreciate your detailed comment.