Are Your Classrooms Color Smart?
We've all in our lives made the mistake of thinking of color as this fixed quantity—some sort of absolute that can be communicated, interpreted and reproduced losslessly. The sky is blue. The tree is green. The car is red. I can write those words, and the colors materialize in your mind. But are the colors you "see" in your mind the same as the ones I intended to communicate to you? In other words, do they match? Surely not.
And the same is true of electronic devices that convey and communicate color information.
In professions that rely on the accurate communication of colors, such as graphic design and print publishing, standards have been developed to help ease this problem. The sky isn't blue. It's Pantone DS 206-7 C. The tree is TOYO 2880. The car is Focaltone 2249. When we use these standards-based colors in documents and send them off to a printer, we know from looking at our swatch sheets just what to expect—assuming the folks at the print house know what they're doing and that our swatch booklets aren't old and faded.
Seems simple. Pantone blue is Pantone blue. Any two professional print houses will produce the same color given the same paper for the color to be printed on. But things get complicated in our everyday lives as we work with and attempt to communicate color, whether it be in the classroom working with students who are on their assigned laptops or in the media department producing electronic and print documents. And we're not just talking about the color looking a little bit off in weekly e-mail newsletters or the colors in the school yearbook being inconsistent with the school's actual colors.
We're talking about problems that can actually become a burden to students and potentially impact their performance. Problems that necessarily arise when working on digital devices.
Color and consistency
As most of you are fully aware, computer displays—both LCD and CRT—produce color using the RGB model: red, blue, green. And the various "mixtures" of those three colors result in what we see on the screen. The mixtures are represented as numerical values ranging from 0 to 255. If red, green and blue are all at 0, the color you see on the screen is black (unless you're working in television, in which case what you see is black plus a bunch of static, but that's a whole separate issue).
So that solves everything, right? The sky is R 144, G 196, B 226. Go into Photoshop and mix up that color, and you know exactly the color of the sky as I envision it. Which is all well and good.
Except that this is almost certainly not the case. On your screen, that color might look pea green. Or lime green. Or light cyan. Or maybe even violet.
And so what do you think that means to a student? A teacher might say something like, "Look at the map of the United States on your screen. Now name the state that's colored orange." The teacher wants to hear "Montana." The student says "Nevada." Who's right?
Depends on the screen. Nevada might indeed appear to be orange.
See, while all computers have the ability to communicate color based on numeric RGB values, none of them display it the same way. CRTs don't display color the same way as an LCD. An LCD from one manufacturer doesn't display it the same way as an LCD from another manufacturer. An LCD from one manufacturer doesn't even display it the same way if that LCD is placed into computers from two different computer manufacturers. Same display, but the computer manufacturer will roll it out of the factory with different default settings.
And the trouble goes beyond even this.
The age of the screen matters. Ambient light and temperature matter. Brightness, contrast and gamma matter. The way a student has treated a monitor matters. All of these factors and more contribute to the phenomenon that most of us barely perceive: No two computers display the same colors.
And so you can wind up with students on different computers perceiving elements of your lessons in very different ways. Not to mention, of course, the problems of headaches and vision issues that can arise from improperly maintained displays.
All right. Big problem. But is it one with a solution?
To a certain extent, yes, there is a solution. A couple solutions, really.
The most cost-effective solution to creating consistent and at least somewhat accurate color across multiple displays is software. It's definitely not the most color-effective, but it's there for you if your institution doesn't have the resources to invest in hardware solutions, which we'll get to below.
Software solutions are generally built into a computer's operating system software. (If you do not have a software color calibration application built into your computers, you'll find links to free software below.) On a Mac running Mac OS X, for example, you go into System Preferences and click on the Displays button. From there, click on the Color button, and you'll see the currently selected color profile for the display, as well as a few buttons: Open Profile, Delete Profile and Calibrate.
Now, on this particular machine, I'm already hardware-calibrated, but I'll highlight some of the steps in software calibration anyway.
To begin calibrating the display, click the Calibrate button. A new window will pop up. There you'll see an option called "Expert Mode." Don't be put off by this. You can't get a decent calibration without checking this option. So check it, and then continue.
The next screen that pops up begins the actual calibration process. Here you simply adjust the little buttons (or crosshairs, depending on the system) until the image in the center disappears into the background. Blurring your eyes can help a bit with this.
Then you continue through several more of these calibration steps until you get to the screen that asks you to set the gamma. As I'm (obviously) on a Mac, I set mine to 1.8, which is the standard for Mac systems. For whatever reason, it also happens to be a good gamma for approximating printed output, which is one of the reasons graphic designers use Macs. If you're on Windows, the standard is 2.2, which also happens to be good if you work in video that will eventually make its way onto standard NTSC televisions.
Once you've set the gamma, it's time to move on to the target white point, which is generally best left at the native value of whatever display you're using.
And, finally, when you're done, the calibration process you've just gone through results in something called a "color profile." The color profile is extraordinarily important in that it conveys information to printers and other devices—including other computer displays—about the way your monitor communicates color to the human eye. Hence you will (or ought to) get more accurate prints out of your computer. And, when you share images between computers—assuming you bother to embed a color profile in those images and assuming the other computers are also calibrated—the colors displayed on the different monitors will (or ought to) appear quite similar.
The critical factor here for a classroom environment is that all the displays used in the classroom be calibrated similarly. And, when using software, that generally means that it ought to be one person doing all the calibrating because, of course, a second person might interpret colors during the calibration process differently, and so you'd wind up with displays whose colors once again don't match.
So the software solution can be tedious and time-consuming for a single person, especially given that displays need to be calibrated on a regular basis—monthly at least—in order to maintain color consistency. The reason? All displays experience color drift over time. This can be accelerated by various factors. But no matter how quickly or slowly it happens, it is inevitable that it will.
In order to relieve some of that ongoing tedium, there's a second option for calibrating displays: systems that incorporate calibration software with a hardware colorimeter. These used to be fairly expensive systems, but there are now excellent models on the market that come in at or around $100. Given that you'd need just one or two to service any number of displays, that's not too heavy an investment to consider.
And the advantage of these hardware systems is that there's no subjectivity involved at all. The colorimeter attaches to the screen and communicates (usually) to the software calibration system via USB. Plug it in, attach it and start running the software. The rest is automated, although there are times when you may be asked question of the software, such as the ultimate intent of the machine being calibrated (video work, print work, gaming, etc.).
Now, I'm not going to go into a sales pitch about all the brands that are available out there. If you or your institution have the cash and demand absolute color precision for print work, you look on the higher end of the spectrum. If you're more interested in color consistency between multiple machines coupled with pretty darned good color accuracy, you can look on the lower end. For my professional and personal work, I happen to stick with GretagMacbeth/X-Rite colorimeters coupled with Pantone color calibration software. On the low end, that's the Huey, which is a collaborative effort between Pantone and GretagMacbeth/X-Rite. It comes in at less than $100, most usually around $75, give or take. It's compact, lightweight and accurate, and the software is extremely straightforward. And there are no extra parts to worry about, like a baffle for LCD screens or suction cup for CRT displays. Those parts are built in. Plus it has a little feature called "ambient light compensation." This continuously adjusts the colors on the display in question in order to compensate for the perceptual fluctuations that can occur as room light increases or decreases. Of course, that feature can only be used on one computer at a time, so, unless you plan to buy one for every computer in your classroom, it's not going to be all that handy.
At any rate, I can't think of a colorimeter put out in the last few years that's particularly bad. There used to be issues with lower-end systems having color consistency problems when working with multiple disparate displays, but those issues have ben minimized in recent years. So, in most K-12 classroom situations, a lower-end model ought to be perfectly acceptable—and certainly better than software calibration in terms of color accuracy in relationship to other devices in the color workflow (cameras, scanners, printers, etc.).
The key here is that, regardless of the particular system you choose to use, the goal must be to provide consistent and at least reasonably accurate color for students. For classes that involve the visual arts—art, video editing, etc.—this ought to go without say, though I know it doesn't for the simple fact that I've known video editors who for years went without calibrating their displays, as well as artists new to digital media who did not have a proper perspective on digital color workflows. (That, of course, amounts to a lot of wasted ink from the printer.) But beyond the visual arts, accurate and consistent color also impacts the learning experiences of students wherever digital imagery is used as a part of the lesson. The digital images students see on their screens were created on calibrated displays and are viewed properly only on displays that have been calibrated likewise.
It's something at least worth considering when the cost of the fix can be so low (somewhere between free and $100).
Now, in all of this, we've considered only the display aspect of digital color workflows. This aspect can be the most important, but it certainly doesn't end there. You'll find more information on color workflows, as well as software and hardware for managing color workflows, at the links below.
About the author: Dave Nagel is the executive editor for 1105 Media's educational technology online publications and electronic newsletters. He can be reached at firstname.lastname@example.org.
Have any additional questions? Want to share your story? Want to pass along a news tip? Contact Dave Nagel, executive editor, at email@example.com.