0

This is for printing on acrylic instead of paper, so I don’t know if the printers are different.

I sent my design to a company in both an RGB and CMYK format. But in the preview they showed me, both end up looking the exact same with ugly, grayed out colors: Image of comparison Keep in mind they both looked exactly the same even though one is in CMYK.

I don’t think it’s the company’s fault because the colors for my other designs came out fine. And I talked to a second company, who gave me the exact same preview image.

What’s going on? Is it just the pink/blue/purple combo?

4
  • Depending on which flatbed UV printer the shop you are using has, it could have a VERY limited color gamut, and that does tend to make bright colors dull out. So it could be the limits of their printer or it could be a bad profile. Can you link to the CMYK PDF of a snip of your file? I can print it on my printer and see what it does. If your other prints came out fine, I would guess that you are out of the available gamut for their printer. I have an older Acuity Advance which doesn’t have the best gamut, so I should be able to answer that question. Also, are they printing white behind?
    – Alith7
    Nov 25, 2020 at 10:26
  • @alith7 Here it is after converting to CMYK in clip studio paint. imgur.com/a/TD86EzA Even though the colors look different now, smit still ends up the exact same muddy gray Nov 25, 2020 at 18:39
  • So there's a couple things with this file. The first, and biggest, is that a PNG can only ever be RGB. If the file is CMYK Photoshop won't even give you the option of PNG. (not sure about other programs) Second, as described below, the purples and blues that you use are out of gamut for CMYK. I'm not sure what program you use, or how your screen view looked the same after you converted to CMYK, but unfortunately, the reality is that your bright colors cannot be reproduced in traditional CMYK.
    – Alith7
    Nov 25, 2020 at 18:52
  • However, there is the possibility that either the printer you used, or find a different one, their printer has extra colors like Green / Orange / Purple or light cyan, light magenta, etc. If you talk with them, they -might- be able to take your RGB file and get a better match IF they are setup to print that way. What you would want to look for is a company that specializes in fine art reproductions. But it's not going to be cheap.
    – Alith7
    Nov 25, 2020 at 18:56

3 Answers 3

2

That particular shade of purple is out of gamut for printing, which basically means it's not reproducible in print. I just sampled it in Photoshop and the out of gamut warning appears. Instead choose a colour which is not out of gamut. Note also that some of the blues (nose cone of the rocket) and bright pinks are also out of gamut.

You should also be aware that nothing is really wrong here - if you print an image that was originally RGB, you can expect to see some colour changes when printing, particularly those colours which are vivid on-screen. This happens because RGB has a wider colour gamut than printing inks, and because on-screen RGB colour is an Additive colour system, and physical pigments (inks/paints) on paper are a Subractive colour system.

enter image description here

2
  • Been using "Gamut warning" for so long I forgot there is an option in color tab for fixing it. Nov 25, 2020 at 10:33
  • @SZCZERZOKŁY - yup, LOL;
    – Billy Kerr
    Nov 25, 2020 at 10:52
1

Here is what I see when I change your picture to CMYK in Photoshop. enter image description here The colors in "Original art" are using, what I call, colors from muddy space . enter image description here

It's the place where white/gray mix with the real color. When changing to CMYK the profiles usually try to "CMYKify" it. So instead of mix of Cyan and Magenta you get all paints. The background "Cloud" is well within 5% off in CMY from what you see in CMYK suggestion for the RGB picture. But that's enough to move the color into grays.

So first of all. Yes it's colors you choose.
Second - profile you choose to change into CMYK. For those I would suggest looking for one that is designed to deal with light pastel colors. Third - Manual correction. In your example Magenta and Yellow are the main culprits. In histogram in Levels you can see that yellow have a large spike in the middle and black. Moving them slighlty to the "light" side would fix that problem.

enter image description here

2
  • So it’s a simple fix then? All I have to do is recolor the art in Photoshop to see which colors are printable? Nov 25, 2020 at 18:41
  • @HubertTyrone Yes, If you use the Billy Kerr instruction and in Color Tab click on the "alert" triangle it will move to closest color that fit inside gamut. If you don't use specific profile for CMYK then it will usually move to those greys. But you can manuall select different one that suit you. You can also work in Gamut Warning view (Shift+Ctrl(cmd)+Y) to have a warning overlay on top of your whole work. Nov 26, 2020 at 8:26
0

End-use inkjet printers want you to send them RGB data. Don't send CMYK color files to print on an end-user inkjet printer if you are expecting anything close accurate color.

End-use inkjets don't really understand what CMYK data is. So when you send them a CMYK file, it confuses them.... so they do the best they can. They convert the unknown color (CMYK) to something they do understand RGB. Then, for output, they convert that RGB to CcMmYyK for their internal inks. This results in multiple color conversions within the print driver itself and often results in color shifts.

Using Adobe RGB is also a possible mismatch. Most end-use inkjet manufactures build their machines for the "unknowning" or "uncaring" user. To this end, they often use the most common, standard color profile which is sRGB. For the average users printing from the internet, Word, or some other general application, sRGB is a perfect choice.

Because you know enough to change your profile to Adobe RGB, you may be introducing the color mismatch there. The printer has to convert your Adobe RGB profile to a profile it uses (sRGB). Any profile conversion "on-the-fly" by the print driver can result in undesired shifts. Working in sRGB will be far more universal overall and will probably result in prints which are more accurate where color is concerned.

I would suggest you work in sRGB rather than Adobe RGB. This is especially true if the goal is to provide files that can be printed by many users on their end-use printers.

If you find prints via sRGB are fairly color accurate but slightly darker, you could possibly adjust for that. You may be able to calibrate the printer itself. Calibrating the printer may help fix the darker prints without any need to adjust the actual artwork. I'm not familiar with Canon printers so I can't say for certain. (Random link about calibrating a printer)

Or, you could adjust the artwork to compensate for the slightly darker inks of the printer. But adjusting artwork would make your files more "localized", which it seem may not be the goal overall.

1
  • Th OP stated specifically that this is being printed on acrylic, which means it is being printed on a flatbed UV printer. That -should- be going through a RIP and all the ones I work with in my shops are CMYK not RGB. RGB through a professional RIP can have random unexpected results due to embedded profiles in the art, calibration of the printer, and a few other variables.
    – Alith7
    Nov 25, 2020 at 10:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.