I love creating designs in colors that turn out not to translate well between RGB and CMYK - and therefore, SwiftPOD (for example) does not print the colors I intended to have.
My colors are just plain white seperated into the Red Channel (Red), and Blue + Green channels (Cyan).
Looks like this:
When I change the mode to CMYK, I get these colors:
Which is a duller blue instead of a light turquoise cyan.
Questions:
Can I recreate the above Cyan color in CMYK format?
How can I convert from RGB to CMYK while preserving the Cyan color?
This question comes up often. Send your artwork off to a printer and it comes back looking dull. Do a search and there are long and short explanations but basically
Some RGB colors that you can see on your monitor (in particular, blue, green and all bright vibrant colors) cannot be printed and/or replicated with standard CMYK inks. Keep in mind that, when creating a file for print, you should always make the original file in CMYK color mode before starting to work on it.
You would think that cyan being basic, is fixed. Even in RGB mode there are changes depending on color profile, top images in Gimp and the difference between sRGB and PhotoGamutRGB profiles.
Much more noticeable if you use say Krita and convert from RGB to a CMYK colour space. The RGB cyan becomes duller and painting in a swatch of CMYK cyan is different again.
Thatâs exactly the thing ⊠I doubt that the color is outside their gamut.
Other printers could easily replicate this hue.
I believe the problem is when trying to communicate the color via CMYK.
I tried asking the printer about which ICC tables they use - but they havenât gotten back to me yetâŠ
(I learned there are some CMYKOG printers out there - but I really think that the âoffendingâ printer (SwiftPOD) could not operate with such a limited gamut - that others have (like Monster Digital and whoever does Redbubble).
Also, assuming they also print in CMYK - they must not use the âsimpleâ CMYK conversion - as that degraded the hues before any actual printing âŠ
I asked Monster Digital about their printing - but no answer yetâŠ
If you have one printer that prints what you want and another that does not then the problem is not at your end.
However, as previously, bright colours become duller when printed with ink, no matter how good the printing company. The last image I had printed was with a 10 ink printer and even then not 100% (but still a great print). You might get a better print from a commercial colour laser photo printer.
Gimp is a RGB editor, so you will always be in RGB workspace but there are variations of RGB. I noticed your example is Apple P3. Going from P3 to sRGB and you can lose some of the cyan tones.
For Gimp 2.10 You can get an idea of what is printable using soft proofing with the printing company cmyk icc and you can âtweakâ using color curves, putting the image back in gamut. Not really a good idea, let the printing company do it. Any half-decent company will take your RGB image and get as best as possible.
This an example https://i.imgur.com/z3GGjQr.mp4
There is a plugin CYAN https://cyan.graphics/ which will export a cmyk image but that is a final operation after all (RGB) editing is complete.
If you do not want to use a plugin then the development Gimp 2.99 will also export a cmyk image.
It is really weird because the print provider is reputable (SwiftPOD) but does not reproduce the colors correctlyâŠ(!!)
Here is another example of the correct Cyan as in my print file (from Monster Digital) with another print from Redbubble (I think) - which reproduces that color with easeâŠ
OK, they are using Brother DTXpro and DTX 6 DTG printers - with CMYK and White inks. (So I assume they have a wider gamut than just CMYK).
Their input format is RGB⊠(!!!) so either there is some sort of internal CMYK conversion - or there is some unnecessary CMYK conversion in preprocessing⊠right?
