Skip to main content
Ken Nielsen
Ken Nielsen
Legend
February 20, 2020
Answered

Mixing RGB into a CMYK file for print is not working, need help

  • February 20, 2020
  • 2 replies
  • 6378 views

We are never done learning in this world as I'm finding out. I sent a file to a printer that came back printed as a disaster. The problem was that a background that was supposed to be black came out as a grey while other elements of art that had black backgrounds printed fine as black, so the background was a mish-mash of some grey and some black rather than all black. MY ERROR... as I see now some of the layers with nothing but blocks that were black were actually RGB (all set to #0000) and the final PDF picked up on the difference and the result was disasterous.  MY QUESTION is, as I go through each layer, HOW DO I SPECIFY that each element like the simple filled with black blocks are CMYK.  I want to be sure as I need to send this job back through to the printer and this time we need to see success and put this error behind us. 

I see that there is a 'Document Color Mode' choice at the bottom of the File Menu pull-down, the choice there was on RGB, Is all I need to do is change that setting to CMYK? Will that affect the entire output PDF? I need to be sure. and color mode - I assume is US Web Coated (SWOP), for this printer.

TIA,

 

Ken

This topic has been closed for replies.
Correct answer Monika Gause

You mentioned that this was an RGB document. Then the swatches are set up in RGB. Converting the document to CMYK does not automatically clean up the swatches.

 

If you want a dark black in the background, contact the printer and ask them for a recommendation. Usually this could be along the line of 100K 60 Cyan for a cool black, but other mixtures for warm black or whatever you want it to look like.

 

The file you send the printer needs to match their file specification and that might even mean that you can send them RGB data, because they have proper color managemnt in place (which might even include proper black conversion). Obviously this printer hasn't. The same conversion that Photoshop does, can also be done when exporting your file in Illustrator to PDF. Color management needs to be set up properly for this to happen reliably (but that applies to Photoshop as well).

2 replies

J
jdanek
Inspiring
February 22, 2020

I wonder if you had a chance to "print" a "proof" of the project before sending it out to the print provider?  Often overlooked, but very much an important part of the process when going to print.  So many factors can be missed just by viewing a file on the monitor.  I suggest you get a copy of Adobe's Print Publishing Guide.  Your PDF conversion is another file that can affect final output.  If your job requires you to prepare files to be printed outside of your company ( open-loop workflow ), such as business cards, then invest in a contract print proofing device.  Or, send the files out to be proofed by a legit service bureau.  When you get the hard copy contract proof back, sign-off on it as your approval and have your customer sign-off on the proof, then send THAT signed proof to your print vendor, along with your file(s).  Odds are you will catch any problems before going to print.

Ken Nielsen
Ken NielsenAuthor
Legend
February 22, 2020

Golden Help Awards to everyone who has responded here. All of your comments are correct. I'm taking in all of the great information as truly there is only one way to do a job and that is the right way, doing all the right steps to ensure a good outcome. 

I've realized that my question was better expressed as 'How do I determine the match in CMYK for a placed RGB image, I cannot convert the RGB image to CMYK as it is only a jpeg image and needs to be matched for 'black' as that is the part that must be matched. I realized that the whole job was trash but need to know, can you read a RGB image on screen with the eydropper tool and get a reading as the dialog shows HSB and CMYK as well as RGB when you take an eyedropper reading.... That is where I got into trouble. I've decided to trash the whole job and start over from scratch. I'm well on my way to creating everything new, fresh from the ground up as I can see THIS is the way to not wind up with disappointment.

Thanks To All, Problems Solved Actually.... Just do it right in the first place and don't try to salvage junk to save work.

Peace,


Ken


meganchi
meganchi
Legend
February 20, 2020

Your file must be in CMYK if you are having it printed. RGB is based on display colors (red, green, and blue light), whereas cmyk stands for pigments (cyan, magenta, yellow, and black). To make sure your art file is using the correct color separations, you will want to open up the Separations Preview under the Window menu. This will show you you a Separations Preview panel where you can turn on and off the color separations individually. If more than CMYK are in there, then it will be displayed, meaning it is a spot color.

    Ken Nielsen
    Ken NielsenAuthor
    Legend
    February 21, 2020

    The areas of black is a box filled with solid black which is the  bacground. It comes out a muddy green-grey, very dark, almost black but not black when it is printed. It's also strange that the page, a business card, looks beautiful on screen but on the thumbnail for the file you can see that the area of the background is lighter and not true black as the placed RGB image is.   My reading for the filled block which is the problem area reads C - 75%, M - 68%, Y - 67% and K 90%.... is that normal for 4-color black when printed? This was a default setting when I dropped the black from Illustrator color block into the background fill. 

    meganchi
    meganchi
    Legend
    February 21, 2020

    Change your reading on the filled block to 100% black within the color panel. Remove the cyan, magenta, and yellow percentages.

     

    You mentioned the placed file is an RGB image, you will want to convert that RGB image to CMYK in Photoshop prior to placing it in Illustrator. That way everything is truly in a CMYK state for printing.

    Terms & ConditionsAccessibility statement
    Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices