Most printers and print buyers are familiar with color bars used to maintain quality, but how many color patches do you really need? And which ones? How do we find the balance between not enough information and too much?
The four-color set: not enough.
The basic CMYK solids color bar many printers use is definitely NOT ENOUGH. This is the rough equivalent of the crayons that are given to kids at the restaurant when they go out with their parents. Every kid knows that this skimpy selection is good for nothing more than scribbling on the paper tablecloth cover, and it is just about as useless for printing.
We don’t need to get too technical here. Everyone has seen press sheets with perfect CMYK densities that simply don’t match the proof in any way. That should really be no surprise, since most images have very little solid color image content. This is probably what caused many to feel that “running to the numbers doesn’t work.” Well, it does work, but not with that skimpy 4 color coloring set.
The eight color set: a little better.
The smallest official Crayola coloring box has eight colors. That is just enough to do some basic coloring activities, and can also give at least a rough idea of what is happening on press. The eight color set would include CMYK solids plus 50% tints of CMYK. This yields a lot more information about the actual appearance. That is easy to understand, since most images are composed primarily of different tints of color.
The nine color set: better yet.
Adding just one additional color to the basic eight color patch set increases the usefulness of the color bar tremendously, if we choose the right color. A patch of CMY tints representing neutral gray is a component of the G7 specification, and is very effective. The logic is very simple. Most colors in real printed images are neither solids nor single color tints. Most are combinations of multiple tints. A three color neutral made of CMY tints is a good guide to what is happening when multiple tints print together. In addition, gray is one of the colors that the human eye is most sensitive to.
The twelve color set: getting better.
The twelve color set is probably the minimum that most kids feel comfortable coloring with, and it is a good minimum for printers and print buyers as well. Adding red, green and blue to the patch sets takes advantage of an old pressman’s trick. Back before densitometers and all the rest, pressmen know that the red that you got by printing yellow over magenta was more important than either the yellow of magenta was alone. So they watched those three colors like a hawk.
The twenty-four color set: now we’re getting there.
We can finish up the process by adding 25% and 75% to our tints and gray patches and well as adding in 3 color solid an paper as well. That’s it. Twenty-four crayons would make any young Crayola artist happy, should do the same for any printer or print buyer.
Do we need the sixty-four color box with built-in sharpener?
No, not really. A color bar with 24 patches gives us enough information about press conditions to know with confidence how well our job is printing on press. And with easily available and inexpensive equipment and software, a 24 color bar can be read and deliver a full print quality report in ten seconds, letting us know instantly know if a print job meets specifications or not. No guesswork, no head scratching, no stressful onsite press OK.
Every kid loves Crayolas because coloring tells a story. With an adequate color bar and the ability to measure it quickly and easily, your color bar can tell a story too.