Sometimes Being Rich Ain't Everything.

Rich black, in printing, is an ink mixture of solid black over one or more of the other CMYK colors, resulting in a darker tone than black ink alone generates in a printing process. (courtesy of Google.)


Here at PSI we highly encourage the use of rich black. We prefer the formula of C-40%, M-30%, Y-30%, and K-100%. The use of it can come in handy across a variety of jobs, and not only does it help the pressmen out a lot and makes for a smoother run, it tends to make the final printed piece look great and "pop" more. 


Now in some cases where there's an image with a lot of black built in (say a Photoshop file or JPEG) laying on top of a black background made in Illustrator...

Things can get kind of tricky if the black of the image and the background don't match and there's a lot of coverage. When I turned separations preview on in Illustrator and turned the Black channel off, this was what I was looking at...

The top left corner is the build (CMYK rich black), and everything else is a placed graphic. This would not be good on press, as there would be noticeable color shifts all over the page (this was a large job).


To alleviate this potential press headache, I had to sample the black in the placed images, copy down the formula of CMYK, then apply that to the background in the Illustrator file. The result now with the Black channel off is...

Beautiful. The pressmen will thank us later.