Color Management

Have you ever had to deal with faculty who tell you that current projectors do not match the resolution or color quality of 35mm slides? Do they still demand slide projectors in their classrooms, 8 years after Kodak stopped making them? Do they insist that ten years of technological advances still have not reached the quality of the classic slide projector? I hear this often from faculty I work with, and for the most part, they are correct.

Over the past few years higher resolution projectors at more affordable costs, have helped with delivering a better resolution. However, most institutions can not afford 15k projectors in every classroom. In talking with our faculty, the resolution is something that they have learned to live with. Certainly the convenience of digital images, along with the brightness of modern projectors have helped convince them in moving to the digital realm.

In my experience color rendering is a much bigger issue than resolution. In order to understand the issue better I recently took a walk around an academic building with a faculty member and looked at the same image on multiple screens and monitors. In fact, in every single room the image looked different. Suddenly I understood how difficult it is to teach fine details, such as how a specific artist puts golden glows around their main subjects, if that golden glow does not show up on every projector.

I dove into this problem headfirst determined to understand what was happening and learned a lot. My first stop was at the Imaging Center we have on campus to talk with our resident photo expert. He introduced me to the topic of Color Management. The basic concept of color management is simple, all colors have very specific definitions, and all computers agree on this definition. However, for various reasons (age, use, quality) the displays we connect our computers to don't all show these colors the same way. So, what we have to do is determine how "off" our displays are and have our computers adjust their output based on that number.

There are some fairly easy tools on the market to do this. We used a product call the "GretagMacbeth". The product contains a receiver that we set on a tripod and point at the screen. Then your computer, projecting on the screen, runs software that displays a series of known colors. The beamer determines how "off" these colors are, and develops a .icc profile for that display. This file tells your computer how it needs to compensate for the projector in color, brightness and contrast.

This ten minute process can dramatically correct color problems in your classrooms or presentation spaces. Our faculty loved the changes and are now more ready than ever to change over to digital. However, there are some problems and considerations. First, you need to remember that this process does not make an image look better, it makes the image look like it is supposed to look. Second, it is ideal to design systems so that the computer recognizes all attached displays. If you have rooms in which your computers feed into a matrix, switcher or splitter then it is likely that your computer does not know that it is plugged into multiple displays and you will not be able to set different profiles. Therefore, managing the color on the projector will make the local monitor colors wrong. In many cases this may be acceptable, as the lecturer or presenter knows how the image is supposed to look, and they are more concerned with the audience's experience. However, in a scenario where both need to be correct, or perhaps a room with multiple monitors of a different model, you will need to provide the ability for the computer to recognize all the displays. Due to the fact that you will be using your own .icc profile, full EDID information is not needed. All that is needed is recognition that the monitors are connected.

On a mac, these settings are extremely easy to use and very intuitive. When the mac sees a projector or other display, you can open the display preferences and get a separate set of preferences for the second display. Under the color tab of those preferences you can easily set the new profile. Under the settings for your second display, you can set a different profile. On the windows side, I have not found an easy solution for this. With Windows XP, you need to download an application, "Microsoft Color Control Panel Applet for Windows XP". Even with this application installed I was not successful in selecting separate profiles for the two separate displays. If anyone has had any luck with this application, please leave a comment and help the rest of us out.

A third issue to keep in mind is that displays experience color shifting over time. As lamps get older or heat alters the panel, there are slight changes in the color. For your pickiest user, you may need to do a re-calibration once a semester to ensure you have the most accurate colors possible. For some of the less picky faculty you may be able to use a single profile for one model of projector. The .icc profiles are cross platform, so this allow you to have a single profile that can be shared with multiple users, on multiple platforms, for a given space.

If you need a real upper, on a bad day, profile one of your classrooms then call in some of your art history faculty. You will put a smile on their face for sure. Going through this simple process is also a great way to continue to get the most out of your investment. It is an easy, yet very obvious way, to take your service to the next level.