CMYK "Rich Black" information and Tips

[billhdz]

Hello folks,

I have been trying to create a "Rich Black" swatch to use with my Adobe Illustrator creations, but after a lot of online research, I find that there are many diffrent opinions out there.  I figure I start this discussion, so that all of the information that we all share, can be available for a lot of Adobe users on this forum.

1. What is your favorite CMYK "Rich Black" pertentage formula?

2. When shoud be use "Rich Black" and when should we avoid it?

3. Would you use "Rich Black" for digital prints?

4. What else can you tell us about your experiences with Adobe Illustrator artwork and using or not using "Rich Black"?

I am hoping that this healthy discussion will be able to help many people for years to come.

Cheers,

Bill

[BorisMel]

I tend to use as rich black

20C 20M 20Y 100K.

From my experience I don't like seeing on the paper 300%-400% ink for making black. Some papers "over-drink" the ink.

Simply 100K doesn't have enough presence and is almost transparent if I overprint texts on backgrounds (I overprint when I need so).

What I do is add 20CMY to the black so it makes it more opaque, while blending with what's beneath, without overkilling with ink layers.

[FuzzyPiglet]

@BorisMel That is the formula I was always taught to use many years ago.

C20/M20/Y20/K100 - It's a 'safe bet' because it won't put too much ink on the paper , too much ink can cause long drying times as BorisMel said and it can also cause the black to turn a horrible crap brown instead of black.

Stay on the safe side

[Stephen_A_Marsh]

Many recommend a single support screen, such as cyan under the black (30c100k), however this can create a “cool” hue to the black (which may not be wanted).

I prefer neutral CMY support tints under the black, cyan is generally run higher than magenta and yellow to achieve a neutral (50c40my100K). The support tint recipe values will depend on the intended output space that the job will be printed in.

For “digital” toner based output, the answer is not so easy! Depending on the device and other factors, one may achieve a richer/darker black when the input is 0cmy100k or if the input was 0r0g0b. For such toner based output (either wet or dry toner), it is best to test rather than assume and it costs very little for a test print with digital.

[bhaines3]

Check with your printer. Each printer knows which mix of CMYK works best for their equipment for a rich black.

[Chuck Rekow]

Excellent answer, bhaines.
If you upload art to some print-on-demand sites (like Ingram Spark) they will caution you to not use a rich black at all—at least for type.

[Pariah Burke]

This is a great topic for The Lounge as it's applicable across many of Adobe's products and beyond Adobe products.

That thread is here Rich Black Tips, Information, and Formulae