Re: CMYK workflow
Tech,
"Hi Don,
When you are not color managing incoming CMYK files, does it mean you guys do with incoming RGB files and convert them to you press profile?"
No. Right now I convert them with the default SWOP profile (just like my customer does). I then proof them using my custom press profile (basically is would be seen as the CMYK assuming my press profile, or my press profile being assigned, before conversion to the proofer profile). This is because I can't use my custom press profile since it was made with a proofing rip and can only be used on that proofing rip. Sucks but true, and why I'm really wanting to move to using standard profiles).
Put it like this, I send the same SWOP CMYK image numbers and/or PANTONE-provided CMYK numbers and/or customer's custom CMYK numbers (none changed by me) to my proofers and plates:
For my Sherpa imposition proof, I use the SWOP profile as source in the conversion, Relative Colorimeric Intent conversion to my Sherpa custom proofer profile which is the destination, and printed on the Sherpa (so the paper is not simulated here, and the Sherpa proof shows exactly what is seen in Photoshop, within limitation of Sherpa).
For my Epson quality contract proof, I use my custom press profile as source in the conversion, my proofing rip uses Absolute Colorimetric Intent to do the conversion to my custom proofer profile which is the destination, and prints on the Epson (so the paper is simulated here, and the Epson shows what my press sheet will look like).
I can say that both proofs match closely. I can also say that if I was using the same profile as source for both - GRACoL2006_Coated1v2 - that the proofs would be virtually identical (so yes closer than I get now, but what I get now is close).
"If I understand you correctly, you prefer receiving CMYK files so there's less or no extra messing around on your end correct?"
Yes. If you have RGB, you may decide to use Perceptual Rendering Intent, where I would probably use the default (which also happens to be the safest rendering intent to use, and gives the closest colorimetric match to the source color within limitation of the destination gamut). So you may get a better conversion of out-of-gamut colors than I would get, but for consistency and to get the closest match colorimetrically to the colors that came in, I would use the default Relative Colorimetric.
"What if our group actually thinks convert RGB files to CMYK is vendor's responsibility and that by converting RGB at the last prepress stage yields best results (after all, once the colorspace is changed, data is lost)? Do you think that's a good assumption on their part or just them trying to hold vendors responsible for the outcome?"
Make sure you embed the RGB profiles in every image, or no telling what you'll get. I honor embedded profiles and don't get any complaints. For untagged RGB, I assume sRGB IEC61966-2.1 (because Adobe RGB (1998) gave me sunburned faces when I used to use it).
"I'm fighting an up hill battle here. I'm all for a strict CMYK workflow because I don't buy the idea of working in RGB and somehow if we work in CMYK workflow we'll screw up or compromised our image qualities."
It doesn't matter to me. Whether I continue printing this way, or start using GRACoL2006_Coated1v2 profile for conversions and proofs (requires also setting up press using G7 to match proofs). If I do move to GRACoL2006_Coated1v2, using GRACoL2006_Coated1v2 profile to do the conversion, of course incoming RGB will look closer to intended appearance when printed than SWOP images printed. Why? Because the image is converted to the actual paper/ink/density/TVI that the image will be printed on. Will some new proofs of reprints not match the previous prints? Images overall will look the same. Individual colors may not, and that's when I would scan the printed piece (if the customer had a problem with the proof and said they wanted to match the previous printed piece) to get Lab values, and use color management (RelCol, BPC, GRACoL2006_Coated1v2 profile) to get new CMYK values so that that specific color does closely match last time when printed this time. I've looked that the different approaches and this one is what I use and intend to use.
Don