ayahhanda

Calibrate and profile monitor

Module Objective: At completion of this module you will be able to calibrate and profile a monitor utilizing given hardware and software tools.

This is generally the easiest yet one of the most important parts of an ICC color managed workflow. If your camera, scanner and printer are all calibrated and profiled but your monitor has a red, green or blue cast to it you cannot expect to visually optimize and edit your images. Photographers are visually oriented, we also like to edit and tweak our images, this makes a calibrated and profiled monitor vitally important.

CRT vs. LCD monitors:

Although LCD monitors are still relatively new to the computer industry, the quality and cost of these units has dramatically improved over the last few years and LCD monitor sales have increased substantially because of this. It really has now come down to personal preference as to what monitor you buy or use. In general either one will work fine for digital color work, although the CRT models are still thought to work better for very critical color evaluation.

Characteristics:

CRT Relatively inexpensive Better for critical color work Heavy and bulky Monitor flicker can be irritating

LCD More expensive than CRT Color changes with viewing angle Thin and light No flicker Thought to last longer than CRT monitors

All of today's color tool manufacturers now have devices that will properly calibrate and profile either CRT or LCD monitors (a fairly recent development). The following step by step demonstration will make use of a Colorimeter manufactured by GretagMacbeth, the "EyeOne Display". While the steps illustrated here are specific to this device and software the general concepts and steps are very similar to other manufacturers devices and software. Please note that monitors do not have to be calibrated and profiled with hardware devices, monitors can be visually calibrated as well, for example a built in visual calibration routine can be found in Apple's OSX Display Control Panel. The use of a Colorimeter however is much more accurate and consistent than visually calibrating a monitor as the accuracy of human color vision can be quite varied. Remember, ideally we want repeatable and predictable color, a hardware device gives us the best opportunity to achieve consistent, predictable and accurate color on a monitor.

Tools:

• Apple G4 Computer OS 10.2.6
• GretagMacbeth Eye-One Display Colorimeter
• Eye-One Match software
• Sony CRT Monitor

Step 1: Make sure monitor has been on for at least 30 minutes. This allows the monitor to reach a stable operating temperature, critical for accurate color calibration and profiling.

Step 2: Install monitor calibration/profiling software if you have not done so already.

Step 3: Attach colorimeter to monitor. This colorimeter is powered from the USB connector on the keyboard. If possible mount the unit at the center of the monitors screen. Simply press the colorimeter into place the tiny suction cups will hold it. You may need to wet the suction cups slightly to get the colorimeter to stay in place.

Step 4: Open calibration/profiling software This module is based on the use of Gretag Macbeth's "Eye-One Match 2" software. Select Monitor as the device to be calibrated/profiled. Prepare the room for monitor calibration, turn off or dim room lights, close curtains or shades if windows are present.

Step 5: Calibrate colorimeter, simply place the colorimeter on a flat surface (sensor down) and then select the calibrate device button in the software. Doing this will ensure that the colorimeter is working properly and set to a calibrated state.

Step 6: Set the monitors white point and gamma. Normally you would set your white point to your viewing condition (color temperature) in this case we are going to set it to 6500 Kelvin. Monitors calibrated to a white point of 5000K or 5500K tend to look too warm (yellow) and dingy (dark). So set your white point to 6500K even if your viewing conditions are 5000K or 5500K Normally you would set the monitors gamma to 1.8 for Apple computers and 2.2 for other PC's. For best results however, we are always going to set the gamma to 2.2, regardless of platform. Gamma basically refers to the luminance capability of your monitor.To determine precisely what this value is for your monitor click here.

Step 7: Set the monitors contrast. The Eye-One match software will prompt you and walk you through setting the optimal contrast on your monitor. This software actually measures contrast via the colorimeter for a very accurate measurement. Some monitor calibration/profiling applications utilize a visual prompt to set contrast, which will not give you the same accuracy.

Step 8: Set monitor brightness The Eye-One software again walks you through this task. The colorimeter makes readings off the screen as you manually adjust brightness until the optimal setting is achieved. Note: Older monitors may not achieve optimal brightness, especially CRT monitors over three years old. If optimal brightness or contrast are not achieved calibration and profile will be inaccurate. If this is the case it might be wise to purchase a new monitor. .

Step 9: Set RGB monitor values This image shows the RGB gun controls for a CRT monitor. Many CRT monitors let you adjust the Red, Green and Blue color levels on your monitor by adjusting the output of the RGB guns. LCD monitors generally do not allow this manual control of RGB. If your monitor does not allow this manual control or any of the previous manual controls, you can simply skip that step. In doing so, you will however not achieve an optimal calibration or monitor profile.

Step 10: Software automatically calibrates and profiles monitor The Eye-One software will now display, white, black, gray and colored patches of known value on the screen. The colorimeter will read these values, compare them and adjust the video card appropriately. When complete your monitor will be properly calibrated and profiled.

Step 11: Name and save profile The software has created a custom monitor profile that you can now name and save. This software automatically includes the current date, which is very useful as it's a reminder of when the last calibration and profile were done. It's a good idea to calibrate/profile your monitor weekly if possible.

Step 12: The Eye-One Match 2 software does one last thing behind the scenes for you, it sets the newly created monitor profile as the default monitor profile for your operating system. The screen grab to the right shows us that the new monitor profile has been selected and will now be used by the OS (Apple's OSX) and any applications, IE: photoshop, that can make use of it.

Great job! You've reviewed the steps needed to calibrate your monitor. Before you move onto the next module please complete the following review questions. These questions will determine how well you remember and understand this information. If you have trouble with these questions you may want to review this information before moving on to module 2.

Review Questions: click on the correct answer

1) When you calibrate a monitor you are in effect describing its color characteristics.

2) You should always select a gamma setting of 1.8 for monitors connected to an Apple computer and 2.2 for any other PC?

3) In general what is the best color temperature to calibrate your monitor to for viewing and editing images?

4) The most prevalent monitor calibrating/profiling device on the market today is?

5) Monitor profiles control the color temperature of your monitor and allow for accurate color display?

OK, hope you did well on the test. Please proceed to Module 2, "Profiling a Scanner".