This happens more often then not. And I really sympathize with a designer that creates a file properly in CMYK in their graphic design program and then they submit the file for print. Then the print comes back completed and it’s not what they saw on the monitor. First off the blue is already muted because its in CMYK and not RGB and then they look at the finished product and it’s completely the wrong color.
So, why is this?
It’s actually pretty simple when you boil the technicalities to basic color knowledge. We all learned in preschool basic colors and the combination of colors to create secondary colors. So, how do you create purple? You would combine equal amounts of red and blue–right? Right. When using CMYK mode, equal or near equal amounts of cyan and magenta has the same effect. It makes purple. But, the goofy thing is that on the screen its a lucious blue. Well don’t believe your eyes, revert to your inner child and simply understand that equal amounts of cyan and magenta will make the print go purple.
So how do I make it blue when the screen shows blue and it prints purple?
From my experience, if you are in Adobe Photoshop. Go to Image > Adjustments > Selective Color.
Then select your blue layer and make sure “Relative” is selected. Then back down the magenta level down about -15%. This will make the graphic on the screen seem muted. But it will print fantastic! Give it a try!
Also, for best results make sure there is not a lot of yellow in your blue colors. If you want a darker blue, use black as a tint.