I’m working on a full color piece in Illustrator which has a few large black and grey areas.
I’d like the black to be a rich black. I was thinking c30 m30 y30 k100. What is the best ways to match my gray areas?
Talk to the production house and ask them what rich black they prefer. There is no single rich black every print provider uses. Each print provider has their own formula for a rich black. And, in many cases, the print provider may want simply 100% K and they will adjust the black to match their own environment. Therefore, the best option is to ask the print provider how they like rich blacks handled.
There are a couple ways to handle tints of the rich black.
The easiest …. make it a Global color. Double click the swatch in the Swatches Panel and tick the “Global” option.
More cumbersome…. hold down the Command/Ctrl key when you adjust color sliders. This will cause all 4 sliders to move in unison.