3 Replies Latest reply on Aug 12, 2010 12:09 PM by Lukas Engqvist

    Unpredictable CMYK

    mbaileyatl

      Has anyone else noticed that you occassionally get unpredictable color in CMYK? For instance, I am designing a print brochure, and the client likes a deep purple (80,100,0,30). This, however, shows up Blue in the Kuler palette. Is there something I'm overlooking?

        • 1. Re: Unpredictable CMYK
          RichaFrost Level 1

          The same thing happens when I take a picture with my digi

          tal camera. Deep purples turn out blue.

          • 2. Re: Unpredictable CMYK
            SageofthePit Level 1

            your screen is using RGB values to create CMYK values.. i created a fill with your CMYK values in Illustrator, then used thos esame values on Kuler and it showed blue instead of the deep purple. But, I then changed from CMYK to RGB in Illy, and used those values in Kuler, and it showed purple.

             

            for some reason there is a disconnect between CMYK-RGB values. In Illy, the RGB values given for the original CMYK values you provided showed this:

             

            Original CMYK: 80,100,0,30

            Original RGB: 68,20,82

             

            now, in Kuler, this is what i got:

             

            Original CMYK: 80,100,0,30

            Kuler RGB:

             

            Original RGB: 36,0,178

            Kuler CMYK: 17,76,0,68

             

            I don't know why there is a disconnect, but if you use the RGB conversion of you CMYK, it should work or at least get very close.

             

            hope that helps somehow.

            • 3. Re: Unpredictable CMYK
              Lukas Engqvist Level 1

              The RGB space you are using is the key to the unpredictable. Kuler does not specify the RGB space. A certain RGB value would be a different colour depending on what colour space it is, also the CMYK colour space would give differerent colours for same values and different values for same colour.

               

              Assumig you are working from SWOP coated, I would think that if you stick to all RGB being sRGB you will get consistent results. There are however some colours that are printable that you cannot create in sRGB. Normally photos are in Adobe RGB, and converted to CMYK (Coated) using Relative conversion, your most saturated colours on screen will get clipped and you may loose detail. Perceptual conversion will give you no clipping at the expense of getting maximum vibrance on those colours that you actualy can keep at high vibrance.

               

              I hope that clarified more than confused. If is hard to give a brief insight into colour managment, put once colour is managed it no longer is unpredictable.