In graphic design and printing, a knockout is the process of removing one color ink from below another to create a clearer image or text. When two images overlap the bottom portion or shape is removed or knocked out, so that it doesn’t effect the color of the image on top.
A good example of a knockout can be seen above. Here the yellow text ‘Hi!’ is knocked out of the blue circle below on the left. As you can see on the right, if you were to print the yellow ink on top of the blue, some mixing could occur and the yellow ink might appear greenish rather than the brilliant sunny hue the designer intends.
The knockout is a pretty standard process in printing. Most design programs will default to doing it when one object is placed on top of each other. Of course, those same programs allow you to make all kinds of changes to these settings as well. In general, knockouts allow for crisper colors unaffected by potential ink mixing. It also makes economic sense in that you don’t want to pay for printing ink you will not see.
Knockout Problems
Unfortunately, knockouts also bring with them their own set of issues. Most importantly, they introduce the need for trapping. Trapping is a way to avoid white gaps in a print should the ink shift and expose the white paper below. You can read more about it here.
For the most part your printer will handle such issues. Prepress and print operators know their equipment best, and therefore know the best little tricks and tweaks to ensure that your design looks great when it comes off the press. Furthermore, newer presses, and especially digital printing presses, make the need for trapping less and less.
If you think there could be an issue, or there is something you are worried about, then as always, talk to your prepress team early and often.
Overprints Possibilities
One thing designers should be aware of though is the possibilities that overprint can present. Overprinting is the opposite of a knockout, and is in fact the intentional printing of one ink over another.
Why would a designer do this? What are the possibilities of it? Well consider our example above. If you are printing with a yellow ink and a blue ink, you are paying for two runs on a press (in this example we are printing spot colors). Usually, if you wanted to add a 3rd color, you would be adding another run of the press, and more money to your budget.
Overprinting can allow for the creation of a 3rd color on your finished project while still only using 2 inks. Pretty cool. The designer needs to take care in knowing what exactly will happen when the two inks mix on paper. You don’t want to end up with a muddy color. And, you definitely need to talk to your printer and prepress team about your intentions. You don’t want a busy prepress team to ‘fix’ your design for you by adding a knockout.
Overprint also can be used for adding a spot varnish to a page, or other specialty inks or services.
cutpasteandprint Printing, graphic design, binding, and promotional product specialists in Huntingdon Valley, PA. We proudly serve the Bucks and Montgomery County areas with superior quality, great customer service, and a commitment to getting you and your the best possible printed materials. Our services include: Digital Printing, Offset Printing, Graphic Design, Promotional Items, Bindery, and Copying.
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