Designing for Print

[st3f]

I’m probably going to be creating some images for CMYK print over the next few months and was hoping to pick the brains of the collective intelligence here to make things look as good as possible.

Left to my own devices, I’m probably going to do the following:
1. Use a colour profile with a wide gamut. Display-P3 would be my choice but that’s only because it’s one of the two I’ve heard of (Adobe RGB being the other).
2. Avoid the corners of the RGB triangle. I’m guessing that I shouldn’t go above 90% saturation in a colour that is close to red, green or blue.

Does anyone have any advice to add to this? Or any improvements on what I am already planning?

Any and all advice gratefully received. Hope you can help.

- Stef.

[Andrius]

Stef, I (unfortunately) have no practical experience with this, but my theoretical knowledge tells me this:

1. Don't use a wide gamut profile. With a wide gamut, you're giving yourself a little more room for error during the conversion process and my monkey brain is telling me that since sRGB is narrower, it's a little closer to CMYK, at least in theory, so when converting there's a minutely smaller chance of things going wrong. In any case, suggestion no. 2 will probably render this point irrelevant.
2. When picking colors for your design, use the CMYK sliders in the Colors window:



This way, you won't be able to pick out-of-range colors for your design.

3. If at any point you want to check what the image will look like when printed, just export it, open it up in the Preview app and choose View > Soft Proof with Profile > Generic CMYK. When choosing colors using CMYK sliders, the result you get when soft proofing should be more or less identical to what you see in the app.

If you do follow my suggestions, I'd love to hear how you get on!

[st3f]

Hi Andrius.

Thanks so much for the advice. It sounds good to me and and has made me rethink my approach:
1. Wide Gamut. My initial gut feel was to try and keep that sliver of blue-green that CMYK has outside the sRGB space by switching to P3. That's always an option if I *really* need those colours but I'd be adding a whole load of unusable RGB space in doing so, increasing the risk of posterisation and possibly needing a switch to 16-bit that might otherwise be avoided. I'm generally comfortable in sRGB so am happy to stay there.
2. CMYK sliders. You know those stupid ideas you hold in your head that are just plain wrong? This was one of those. I always assumed (for what reason I am not sure), that the CMYK sliders were a bit of a toy and that they were just another way of manipulating the same colour space, i.e. that RGB(255,0,0) would produce exactly the same colour as CMYK(0,255,255,0). So, thinking them useless, I never tried them.
3. Soft Proof. I did a soft proof of an RGB colour wheel with lots of bright colours and found that my mental image of CMYK space was completely off. I was expecting reds, greens and blues to be muted but cyans, magentas and yellows to stay bright. Instead everything seemed to get a little duller. So I did the following:

Incorporating 2 and 3 I drew the attached image featuring:
* RGB circles Screened over each other.
* CMY circles Multiplied over each other.
* The Hue and Brightness of the resulting colours plotted on a graph.

I was really surprised at the following:
1. Just how attenuated the brightness was.
2. That it was the brightness that was attenuated. I had expected it to be the saturation. I don't know why.
3. That there were significant shifts in hue.
4. That many already dimmed colours were further muted when I used Preview to soft proof.

Thanks again for your help. Whenever I dip my toe into colour theory I am always reminded of not only how little I know, but how much isn't as I would expect it to be. This will be a difficult journey but you have made it significantly easier.

All the best,

- Stef.

[Andrius]

To be honest, I wasn't expecting the yellows to get dulled quite so significantly either — the Generic CMYK profile might not be the best to proof with as other CMYK profiles don't dull the brightest colors quite as strongly. If you know where you'll be printing these images, it would probably be a good idea to get in touch with them and ask whether they have an ICC file (or would let you know where to download one) of their printer's profile that you could use to proof your images accurately. As Generic CMYK might potentially by the sRGB of the print world, while their printers might have the CMYK-equivalent of P3 color. You know, potentially. If that makes sense... P.S. Installing a custom color profiles is a simple as dropping an ICC file into a system folder.