Expert: LizaL - 10/11/2004

Question
Hi,
I am trying to convert black and white line art bitmapped images
into a rich black (100%K 60%C 30%M 30%Y). When I convert from
bitmapped to grayscale to CMYK, Photoshop automatically
changes the blacks to 75%C 68%M 67%Y 90%K. Is there a way to
get it to automatically convert it to the rich black percentages
that I need?
I have tried selecting all and using the correct black as a fill, but
it seems crude and messes up the really fine lines.
THANKS!
Paul
paul@goofyfootpress.com

Answer
Hi Paul,

Hmmm... line art is usually created and treated as a vector image, not a bitmap.

Plus, "rich black" varies a little in color theory circles, but it's generally defined as 40C and 100K; I've also seen it as 60C, 40M, 40Y, and 100K. The printers I've worked with have usually always used the first formula, but the printer I used when I was an art director supported both, depending on the image.

Now going back to the first issue, if you're concerned about the integrity of the fine lines, which is natural concern, I'd open and edit your images in a program that supports vector drawings, like Freehand or Illustrator. There you can create and define the percentages of color you desire for your rich black -- and save that color in your color palette. That's what I would recommend, if what you're working with is line art, as you say.

Using a vector program to edit line art is the only way to go. Photoshop will take line art and rasterize it, thus giving it a fuzzy edge. Then, as you mention, trying to fill those images will only worsen the situation.

If you absolutely must use Photoshop on line art, and you want to define a new color, you can do that, but I'm not aware of being able to save it in a user-defined color palette.

Think about using Illustrator, if you have it, or a vector-based drawing program!

Hope this helps --

Lisa