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RGB and CMYK workflow

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Redcap
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I work mostly with digital media, and just got a gig in which my work is going to be printed; so my question is about color and professional printing.

Every time I have worked with 2d graphics I have gotten better results working in RGB vs CMYK. My computer would convert when printing and the results were almost exactly what I saw on screen; however, when working with CMYK my colors were always dull, lifeless, and flat; even when working with a cmyk laser jet. So my workflow always favored RGB.

The gig I have right now, the commercial printer wants the files in CMYK. So my question is should I do the art assets in RGB then export them to CMYK or work solely in CMYK the whole project? I am just afraid that the images will be dull and boring like they were if I work only in CMYK as opposed to converting.

Thanks all.

ilta
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work in RGB, convert to CMYK last, check for true black

Unless you have a professional CMYK monitor (unlikely, they're ferociously expensive) you're always working in RGB because that's the physical reality behind your screen -- red, green, and blue LEDs. Generally the advice is to therefore work in RGB mode and then, as the final step, convert into CMYK before sending them off. Technically, that's what your printer driver does, usually not too badly.

If you work in CMYK mode you're forcing an extra conversion (from the CMYK file to the RGB monitor), and every change you make has to go back through that conversion process into the CMYK file, then out again into RGB so you can see it on your screen. As with all translations, you'll lose something. This is also why you shouldn't convert a file back and forth.

The reason the printer doesn't want an RGB file is that THEIR professional printers, unlike your desktop inkjet, do not handle the conversion so they would have to take an extra step to convert a file themselves, assuming they even have the right software (most do, but it's not a given), and in any case you'll get better results converting the original photoshop file than they would converting a single-layer jpg, which is usually what you send them.

So the most accurate results, assuming your software is good and your screen is color-matched (it is, right?), will be to work in RGB and then convert into CMYK. You won't see much difference in the program (remember, it's converting it back to RGB for you), but if you look at the JPGs outside the program side-by-side you will. For instance, note the "green" tone in this CMYK image I sent to the printers:

http://www.flickr.com/photos/isaiaht/4503553860/in/set-72157623750017456/

Here's the original RGB version. When printed, the colors looked pretty much like this, as intended.

http://www.flickr.com/photos/isaiaht/4502828059/in/set-72157623750017456/

Ultimately, final color fidelity depends on the program that's doing the conversion. For instance, I've NEVER been surprised by Photoshop, although I have kicked myself when I realized that something that I thought looked like a nice wood tone actually looked like poop when it was printed and in my hand. I went back and looked at the file, though, and yep, poop. My fault. That's more about the difference between physical and digital media, I think -- on the screen it's backlit and that does certain things to your perception of the color and tone. This may be what you mean when you talk about "dull, lifeless, and flat" tones.

The other tip is to make sure that, after you convert, you're using True Black (on non-tiny-text areas). I won't go into it here, but here's a tutorial:
http://www.bittbox.com/all/photoshop-101-true-black-cmyk

Don't use True Black on small text, since it uses multiple inks and they might not line up exactly. It's more to make large fields of black or big headlines not look gray.

Also, I have been (unpleasantly) surprised by the free alternatives like GIMP and Paint.net, which aren't really designed for professional (ie CMYK) output, and the various work-arounds and add-ons that people have grafted to them. I've also been surprised when I sent a file to someone in RGB and they converted it using god-knows-what, which fate has forced on me once or twice. But if you have no choice because you don't have Photoshop, then that's just something you'll have to take into account.

You might want to consider creating (or requesting) a swatch using universal color values like hexadecimal.

And finally, finally, don't forget bleed and error margins! Each printer has a different standard (usually 1/4 inch, sometimes less), but don't make the mistake I did with my first print job and not take it into account. I had to redo much of the entire job, which didn't take long since I knew what I wanted, but was super annoying.

Redcap
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Wow, this was an awesome

Wow, this was an awesome response and should be stickied into the how to section.

Okay, everything you said aligns with what I thought and it makes our jobs so much easier being able to work in RGB.

I do have Photoshop, so the conversion will be no problem; but is there a specific setting that gets better results in your opinion or just the default convert?

Thanks!

The Game Crafter
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Joined: 06/09/2009
Flatten your images

One other quick recommendation. If you're working in Photoshop, flatten your images *before* you convert to CMYK. If you don't, then sometimes you'll get different color shifts on different layers, which can cause some unexpected results.

Cogentesque
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Heya Redcap, everything said

Heya Redcap, everything said in the post is exactly spot on. To add in my 2p (im english :P) I would sum up with:

1) remember bleeds ALWAYS (3mm-5mm)
2) Don't ever use spot colours if you are printing cmyk - you can get some NASTY results if you are "ad-libbing" with your abilities (unless you are specifically told too)
3) Try and stay away from tansperency if you can (again, in certain cases it has some funky results)
4) if using any adobe software then remember to "export" to pdf as opposed to "print" to pdf
5) Stick in rgb the entire way and then let adobe convert it to whatever cmyk profile the printers want (its FOGRA 27 for my printers at work) eg: .png's are only in rgb colourspace and are way easy to manipulate compared to crazy big layered .tiff's
6) there's not TOO much different 'tween cmyk and rgb if you use your head. The colour spaces share most tones except very saturated blue, red, and green - to guide yourself to have less of a possible suprises (you probably wont anyway) don't expect rgb red (255, 0, 0) to come out as you can see it (or true blue or green).
7) Calibrate your monitor. You can spend bajillions of coins getting ultra-pro monitors or you can calibrate yours (http://www.wikihow.com/Calibrate-Your-Monitor) basically: make sure "white" is white and make sure "red" is red and not "red with an orange tinge" as most uncalibrarted monitors are.
8) try (if you can) and always use a DPI of 200-300 (300 better) and never go below 90 or so <- unprofessional
9) and CMYK print will always come out slightly "duller" than the monitors - basically, monitors are electrical powered bright lights and cmyk is actual real world stuff - but try not to "trick" the conversion process in anyway. eg. if you say "it will dull out in cmyk print so i will max the brightness of my colours now" it will simply come out funky-lookin' and a little bit forced

tl;dr : Do it in RGB and convert to CMYK at the very very end and you'll be fine :)

mindspike
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Joined: 09/06/2011
good to know

Thanks for both the question and the answers. I'm prepping artwork for production, and the convert from RGB to CMYK was something I was concerned about.

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