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mitchrenton
21 May 2008, 11:21 AM
I am currently printing a brochure and the logo i have been given is a jpeg with RGB color setup. When i change it to CMYK for printing the bright green turns into a dull green. Is there anyway of gettting a bright green in the CMYK profile? I would use the RGB profile but the black doesn't match the CMYK profile of the rest of the brochure. Any help would be much appreciated

Mitch

alvo
21 May 2008, 12:51 PM
The color gamut of CYMK is much smaller than RGB and as a result there are a lot of RGB colors that can't be printed in CYMK. The only way to get a color close to matching costs more to print, and that is to add a fifth color plate and print the color using a custom mixed green ink (use Pantone or Toyo color matching systems to find the color you need).

By the way, if you're using Photoshop, the default RGB > CYMK conversion setup isn't optimum for the average photo on most presses. The Black plate generated is too dense for most uses. Changing the GCR value in the setup from "medium" to "light" will make jobs much easier to print on the press and be less prone to color problems (the only time to have a heavier black plate rather than a "skeletal" black is when you need to maintain neutral grays, such as a photo of a pile of silver coins where a slight color shift would be noticeable). You might also want to change the maximum ink coverage from 300% to 270% or 280% unless you're using a high end press on top quality paper.