What does it mean when printers and designers talk about “Rich Black” ? Hint: It’s not somebody named Richard. Rich black is any black color that is made up of more than just black ink. The addition of other inks (Cyan, Magenta and/or Yellow) adds saturation, or richness, to the black. This can be good for deep heavy blacks, but bad for printing — unless it is used with care.

First, a quick primer on offset printing. Actually, that’s already been written. Check it here. Full-color printing is usually done with four different colors of ink (Cyan, Magenta, Yellow and Black), called “process” colors. Each ink is printed on the page in a particular order, one over the other. The transparency of the inks and the use of halftones gives you the spectrum (or “gamut”) of color you see on the page. A color photo, for example, will likely contain all four inks, giving it a dense, saturated look. Plain text, on the other hand, is most often printed solely with black. Since type is small and needs to be readable, a single color works best. Use all four and you’ll end up with registration problems (the alignment of all four color printing plates). Also, it’ll use four times as much ink, and you’re not made of money, right? Maybe that’s why they call it “Rich” Black!

So what does this have to do with vector illustration? Contributors should understand when to use rich black, and designers should know what to look for in the files they download, so that their printing jobs will go smoothly.

Rich Black in Illustrator

In this illustration, the “type” is plain ol’ 100% black. If it were actually meant to be read, that would make sense, for the reasons stated above. The hair and the suit are made from rich black, to give it more “pop.” The actual four-color breakdown in this case is 37% Cyan, 38% Magenta, 15% Yellow and 96% Black. That adds up to 186% total ink. You can theoretically have 400% total ink (100% of each color), so this particular black has less than half the total possible ink.

Notice I said “theoretically” in the previous paragraph. There is no scenario in which you’d want — or need — to lay down 100% of each of the four process inks. Ink is liquid, and paper is, uh, paper, so all that fluid on paper is not a good thing. Depending on the kind of paper and the quality of printing, the most ink that a press can handle is somewhere in the 240-300% range.

A common breakdown is:

  • 60% Cyan
  • 40% Magenta
  • 40% Yellow
  • 100% Black for 240% ink

Rich blacks can be “cool,” or “warm.” Cooler blacks contain more Cyan (60C, 0M, 0Y 100K , for example), and warmer ones beef up the Magenta (0C, 60M, 30Y 100K). Yellow tends to neutralize the other two colors, so a 4-color rich black is most commonly used. Most print shops have their own rich black specification, so check with them before submitting files to print.

Take a closer look at our man’s hair. The sideburn is made of 100% black alone. You can see a subtle difference between it and the rich black. In Illustrator, you can choose to have the blacks display accurately on screen, so you can see the difference quickly.

You can also choose to display and output all blacks as rich black. These settings are found under Preferences > Appearance of Black.

Guidelines for contributors

As stated previously, too much ink is a bad thing. If you use rich black, make sure it falls into the acceptable range of total ink. Do NOT use “Registration” as your rich black. Registration is %100 of each ink, and is used for crop marks and registration marks. Do not create a spot color swatch for your rich black. Any spot color will create an additional plate to print. Knowledgeable designers and pre-press technicians will be on the lookout for unintended spot colors, but it’s best to make the file as easy to print as possible. You can make a “Global” color swatch for your rich black, so it is easy to identify and replace, if necessary.

Guidelines for designers

Set your Illustrator preferences to display all blacks accurately. This will give you a better visual cue of what blacks are used. Use the Separations Preview in Illustrator. This panel can be accessed via the Window menu. It allows you to turn on and off individual process colors to preview what will print on each plate. If you notice, for example, that small type appears on each plate, you know you’ve got a potential problem. Plus, it’s just interesting to see what will print on each color plate. Well I think so, anyway.

To find and replace any rich blacks you want to change, select an object that is filled with the black, then go to Select > Same Fill Color. You can then fill (or stroke, as the case may be) every selected object with the color of your choice.

If you’re having any trouble with the vector file you download, don’t hesitate to contact the artist, or one of the friendly iStock Support people. And always consult your printer for advice on rich black.

Image credits:

Bills Too High? by RUSSELLTATEdotCOM

Thanks to daveturton for the article title.


Cheryl Graham (FreeTransform) began uploading to iStock in December 2005. She creates Adobe® Illustrator® tutorials for the Layers magazine Web site, as well as her own blog, freetransform.net.

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