© 2003 Ron Ellis        First published in New England Printer and Publisher


Calibrating and profiling displays: How to make it work

By Ron Ellis


While everyone is aware that monitors can be calibrated, few people realize how easy it is to do. This is mostly because the ‘recipe’ for doing it is obscure and unknown. The necessary software and hardware has been around for years, but it hasn’t been easy for most people to get everything to work. For this reason there is a great deal of skepticism about monitor calibration.


Having the right tools

You need to have the right hardware and software in order to calibrate a monitor properly. The hardware needed is a spectrophotometer or colorimeter that can be attached to the monitor. Not all spectrophotometers can be used to read both cathode ray tubes (CRTs) and liquid crystal display (LCD) monitors, so if you think you will ever need to read an LCD display make sure you choose one that has that capability.

Some existing spectrophotometers such as the GretagMacbeth Eye One spectrolino can read displays, but many people use a less fragile and less expensive device used specifically for calibrating and profiling displays. Popular devices such as the Monaco Display Optimizer and GretagMacbeth Eye One Display cost a few hundred dollars and can calibrate both CRT and LCD displays. One note of caution — if the device includes suction cups look for another adapter before attaching it to the screen. Failure to do so can rip the coating right off your screen. Most of these devices come with software for calibrating and profiling the displays as well.


Calibration and application software and a need for two profiles

The software needed falls into two categories. The first is the software used to calibrate and profile the monitor. Nearly important is the use of application software that allows you to apply profiles. This can be confusing but the main concept here is that to make this work usually involves the use of two profiles. The display profile works at the system level and helps make the display work as accurately as possible. The second profile, say of a system like a Matchprint, works within an application such as Photoshop and allows you to simulate the system that has been profiled within an application. The monitor calibration and profiling software is used first.

Normally the first step involved is to calibrate the monitor. The software typically asks you a series of questions that involve setting the brightness, contrast, and RGB settings. These questions are interactive.

For instance when the software asks to turn the brightness up all the way, and then using the measurement device will perform a series of measurements to get the brightness and contrast on the monitor to its optimum settings. Once you have adjusted these settings you then move on to profiling.

While the calibration step is designed to make sure that the monitor is running as well as it can, the profile is used to make the color display as accurate as possible. The profiling results in an ICC profile used by Apple’s Colorsync or Windows ICM color management systems.

The software uses the measurement device to read a series of patches and characterize the monitor. Once read in the software, a corresponding profile is created and the software sets the monitor to it. The intent of this profile is to display color as accurately as possible on the display monitor. One note: at this point if anyone changes or adjusts brightness, contrast, or any other monitor settings, the entire calibration and profiling setup becomes invalid. Also, displays change over time so the process needs to be repeated on a regular basis to ensure that the monitor calibration and profile are accurate.


Not quite finished yet: A CMYK profile is still needed

Once you have profiled the monitor you would think you were done, and this is the part in the process that many people find confusing. After calibrating and profiling, we now have a display that renders color as accurately as possible on the display. This, however, has little to do with representing color as it will be on press. With a calibrated and profiled monitor you are seeing color as well as it can be displayed in RGB on your screen. To make the color relate to the printing process we need to overlay a CMYK profile on top of it.

While the system takes care of color managing the monitor itself, the application is responsible for color managing the system we are trying to emulate. This is further complicated by the fact that some programs manage color well and others don’t. For example Adobe Photoshop manages color extremely well, while Quark Xpress does a poor job of it.


Adobe products excel at color management tools

As a general rule, new Adobe applications such as Photoshop, Illustrator, Indesign, and Acrobat provide excellent color management facilities, while older applications such as Quark, PageMaker, and others do not. Adobe has really nailed color management, which makes using their applications for color management easy.

A good example of this is Adobe Photoshop. If you open an image and want to simulate it, select the Proof Setup option and select the profile of the system you are trying to emulate, such as a Matchprint or your actual press profile.

Following this procedure is the proper use of the operating system to color manage the display, and allows Photoshop to color manage the image to match the system you are trying to emulate. (Oddly enough, choosing the same profile in the color settings preferences doesn’t get you the same accurate simulation, and depending on the quality and purpose of your profile, can actually cause problems with your RGB to CMYK conversions).

In the newest Adobe applications this proof setup screen functions the same, which means that even programs like Acrobat can provide you with excellent on-screen proofing simulations.

So keep in mind that you will most likely have good luck in Adobe applications using the above technique, but in other programs it may not work as well. In addition, if for some reason you feel the profile does not accurately represent on the screen what you need, you will need more robust color management software to edit the emulation profile and get the results you need.


Another variable to consider

One other variable that we haven’t spoken about much at this point is the display system. One of the best values I have seen right now is the LaCie Blue Eye series of monitors. They calibrate well and are inexpensive. Keep in mind that monitors degrade fairly quickly so if you have a monitor over two years old you probably shouldn’t even consider trying to profile it.

LCD monitors have less range than CRTs. In a CRT, the actual way the card shoots color is modified, but on an LCD that is not possible, and the color range of the device may actually be clipped. Some of the newer Apple Cinema LCD displays do not contain contrast and do not even let you adjust brightness unless you are in OS X. There are a variety of opinions on this, but for my own taste I prefer using a CRT monitor to do calibrated displays if color really matters.

Calibrating monitors can seem like it doesn’t work, but once you put all the pieces together and use the right applications, the results can save you time and money. While it is never as accurate as a good proof, it can save you several steps as you adjust the obvious problems before committing to a hard proof or plates.



About the author: Ron Ellis is a prepress consultant specializing in workflow training and integration. He worked in the commercial printing industry for 18 years and brings a strong background to all aspects of prepress. He has consulted on numerous CTP installations and he provides color management, integration, training, workflow development, and troubleshooting solutions to the graphic arts community. He can be contacted at 603-498-4553 or through his web site at www.ronellisconsulting.com.