Cmyk Rgb

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Cdztattoo Barreto

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Jun 30, 2024, 9:23:58 AM6/30/24

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I'm trying to save a photo with a CMYK color profile to send to a company who will print it for me. I've looked at the color profiles installed on my computer, and quite a few CMYK profiles appear to be there (in /Library/Application Support/Adobe/Color/Profiles/Recommended). I'm not sure if they need to be in the "Profiles" folder specifically, or if it matters that they're in a subfolder of that folder. This is on a Mac computer, by the way.

cmyk rgb

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Above and beyond what Jeff and John have told you, be VERY careful converting RGB to CMYK unless you have the specific ICC profile for that print provider. Probably a lot safer to send them tagged RGB and let them convert the data. Converting with a profile that isn't specifically targeted for the print process will produce huge headache's for you and the shop and potentially awful output which is going to be expensive. Ask them if they can accept RGB and send them maybe sRGB which of course you can do from Lightroom.

thedigitaldog - interesting point. Thanks for the heads up. If only LR 6 wasn't so much slower than LR 5.7 - I'd take advantage of that! As is I just go into bridge and use ACR to convert to CMYK. It offers a direct save option.

Most people require CMYK images because they think they need it for print caused by a lack of accurate knowledge. And for photos it makes less sense as it would make for Photoshop. You need to keep the appearance, not the CMYK values.

Ya... I teach photography at a graphic design school and it seems like I spend half my time telling my students to keep things RGB, regardless of what their other profs say. I'll occasionally get a client who wants both rgb and a specific CMYK space (like I did this morning) - otherwise why work in a smaller space?

FWIW and perhaps OT, CMYK, depending on the flavor (say SWOP V2) isn't necessarily smaller than RGB (depending on the space, say sRGB). At least if we're talking about size in terms of gamut. There are colors in SWOPv2 that fall outside sRGB gamut. Getting back OT, there are lots of workflows where one has to supply CMYK. Unless you have the profile for that specific output device, IF you can send RGB, do so. Nothing will hose the color of a job better than sending CMYK converted using a process not intended for that output device.

In addition, CMYK is very much dependent on geography. Here in Europe, most commonly used are either ISO Coated (eci) 300%, or Coated FOGRA39. SWOP isn't used anywhere, and the Photoshop default is probably responsible for more bad color here than anything else. People just hit Image Mode > CMYK without any idea what they're doing.

But if your printer company has told you that it uses a particular CMYK profile (such as FOGRA27 Coated that my print company uses) shouldnt you always use that, and if they havent shoudn't told you you use PhotoProRGB instead of sRGB ?

For example if you are working on a file in Lightroom and you do a SoftProof to sRGB and it shows lots of out of gamut colours, then you do a soft proof to the particular CMYK profile and it shows less and different out of gamaut colours ( i have plenty of files like this). If you now export the file as sRGB its going to have to clip/modify those colours that were invalid for sRGB even if they are fine for CMYK. Then when the printer company converts the sRGB profile to a CMYK profile it has already has some incorrect colours and the problem will worsen when you then convert to CMYK to deal with the colours that the CMYK cannot handle. These colours may not even be the colours that were shown out of gamout when you SoftProofed to CMYK initially because the conversion to sRGB wil have converted the colours that sRGB couldnt handle so when map back to LAB the colours will not be the same as the original image. You could get round this by modifying the image so it doesnt show any out of gamout colours but you would have to modify it so it doesnt have out of gamout for not just the CMYK profile but also the sRGB profile even though the sRGB profile is not being used for printing! Additionally export as a CMYK profile will allow you to decide whether to use Perceptual or Relative conversion, you dont have this control if the printer company does the conversion (but to export as CMYK you will have to open the image in Photoshop and do it from there, although you can softproof CMYK profiles in LR6 you cant export with a CMYK profile)

Alternatively if they haven't told yo how they would print by all means softproof to sRGB and make some adjustments to improve the chances of a good print. But wouldnt it be better to embed the a ProPhotoRGB as this will always better represent the colours in the original image allowing the printer company to do a better job of converting the print to whatever method they use. The only disadvantage to this method is you would have to export as a 16bit tif rather than 8bit jpeg because 8bits is not enough bytes to properly represent the PhotoPro colour profile.

Don't worry too much about out of gamut colors, that's a fact of life and good ICC profiles with good rendering intents will by and large take care of this during conversion. The Out of Gamut Overlay is buggy and inaccurate, not even worth viewing IMHO:

I understand that ProPhoto is mainly for editing but it does always allow you to provide an image to a printer which they can convert to their preferred rgbprofile or cmyk and at least the image hasnt already been degraded by the process of converting to sRGB or adobeRGB.

It's only risky if the printer is rather clueless about color management and RGB working spaces. So Adobe RGB (1998) would be as risky and sRGB (or better, ColorMatch RGB) would be something I'd send to such clueless people.

Adobe RGB (1998), sRGB, ColorMatch RGB and ProPhoto RGB, among others, are just RGB working space, editing and archive spaces. They cannot be directly output to print, they are source color spaces for the final destination (output to print) color space. What's risky is dealing with any RGB or CMYK color space with people who don't understand how to treat them.

Fast forward to 2023. Business card printers for example all seem to want a photo file uploaded in CMYK which is a problem for me to get the conversion to look right in PS CC. Check Vista print who is possibly the largest business card service in the USA. They want my file in CMYK color. As a test, I sent them an aRGB file and the color on the cards was not good at all.

On the top left, you can see what Color i would like to work with. I was choosing the color in RGB. Because i wanna use this color also for something to print, i wanted to make my color for CMYK. I used for that multiple online RGB to CMYK converters to be sure it's the right one. On the left of the picture, you can see a screenshot from one converter. (The Document was set to CMYK).

And now my problem. On the right is what color Affinity gives me when i use the CMYK color code. I also tried the CMYK colors in other programs, they all gave me the correct color which i want on the left. But not Affinity.

The Color Format is set to CMYK. Because of trying out and searching for Color Profiles, I ended up with "Uncoated FOGRA29". I did not change any Color Profile Settings in Affinity. And also no changes to the OS itself.

Matching cmyk color across documents: How do I match the lighter green at the top of the first image to the solid green in the second using CMYK slider codes? As you can see, using 89-0-89-32 in both documents gives me different results. Eyedropper doesn't work between docs.

On macOS, the Color Picker always copies color values also when copying across different apps and anywhere from within the screen, while on Windows the display color is copied and converted into the destination document color space, which is probably what is most often wanted:

I exported a palette based on the flower image, which has the correct warm green on top of the gradient. However it does not contain this green, therefore I was unable to use it when imported into the other image.

This video shows how you should be able to use the Color Picker tool to copy color values across documents. It is not absolutely accurate especially when needing to copy a value from a gradient, but works ok when both the source and the destination have the same color space. The video also demonstrates the error in the Gradient color definition box.

size of a 100mm wide test square opens as 100.19mm thats not very good !
There is a slight gap beyond the 100mm square, but why ? I seem to remember eps was accurate.
No doubt the square itelf is 100mm but why the small margin ?
Method used is select the objects, then export selected as ai,
options . preserve model scale 1mm = 1mm cmyk

My only other choice would be to make the export black, turn it into a channel when opened into pshop, then dump a cmyk mix into the selection on screen, but the original in black with black panel lines wouldnt be easy to work on !