How can I fix printed colour problems with images designed in Photoshop?

Question

I design artwork in Photoshop to be sold as downloadable files for printing.

However, I'm having ongoing issues with printed colour problems and seem to be going round in circles with this problem. I design the files in Adobe RGB and make sure no areas are out of gamut, as I'm assuming most people will print on their home printers or take the files to copy shops.

However, when I do a soft proof in Photoshop for my Canon Printer the colours change pretty dramatically - significantly darker, duller and more washed out. When printed they look just as bad, so the soft proof is pretty accurate.

Adjusting the colours of the artwork so that they look better on my printer isn't an option because I'm selling these as downloads, so the files will be printed on a wide range of printers.

I know that it is impossible to control how colours are managed once the file has left my hands, but I really want to be sure that it's not a problem with the colour profile I'm designing in, or something I'm doing wrong. I got hold of some PDI test images to do a comparison, and while they did print out a bit darker there didn't seem to be a noticeable difference between what was on screen and what printed on paper in terms of colour.

I certainly didn't look at them and think "YUCK!" like I do when I print out my own designs. This makes me think it's something I'm doing wrong. Having said that, when I took my designs to a copy shop they printed out very decently on their laser printer. I'm at a loss as to what I should do. Any insights would be VERY much appreciated! Thanks.

Answer 1

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.

_{A possible exception to the above statement is if your particular printer has an onboard RIP internally. Some higher-end inkjet printers do come with a RIP (raster image processor) and these are designed to convert CMYK for output along with vector data and other postscript things. These typically are the more expensive printers (~$500+), not the $150 printer you pick up at Amazon, Staples, etc. And generally they market the printer as having a RIP, because it's a big selling point.}

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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 found via Google about calibrating a Canon 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.

Answer 2

What you probably doing wrong is using RGB, and not using a CMYK swatchbook.

If you want to be sure that colors print as expected, you must refer to a PRINTED sample of the color, created with CMYK inks. I recommend Trumatch color swatchbooks. I guarantee you will get the colors you expect if you use CMYK swatches and input those CMYK values into Photoshop or any other professional graphics program.

Using RGB is a recipe for mismatch. There isn't any magic to using CMYK ink values with CMYK inks and CMYK swatchbooks. But anything else is voodoo.

Yes, yes, I know, RGB can be translated, and many print drivers and amateur graphics programs try to accommodate people working in RGB. But it makes no sense and isn't the way things work in the real world. 100% yellow and 100% M is a particular red that always looks the same in CMYK and never looks like 100% R.