How (& Why) to Calibrate Your Monitor
Posted Monday, 7 March 2011 by Louis Au in
Louis Au,
Photography,
Technology
For Digital Content Creation Professionals, the ability to control colours is essential. With today's complex colour management workflow, getting colours to match between devices can be challenging. If your monitor is not displaying colours and shades accurately, then all your efforts in image adjustments will be wasted. The results on-line or in printed media will be unpredictable.
So, what is monitor calibration and why is it important? Monitor calibration and profiling is the process in which you measure the colour gamut of a particular monitor with a colorimeter (measuring instrument) and produce a description of this information in a profile so that applications like Adobe Photoshop can render the colours on screen accurately.
The goal of monitor calibration is to bring your monitor into compliance with a predefined standard white point colour temperature of 6500 Kelvin. This process helps you eliminate any colour cast on your monitor, makes your monitor's grays as neutral as possible, and can standardize image display across different monitors on different workstations.
Having a working environment calibrated to the industry standard will ensure consistency and guarantee WYSIWWG (What you see is what we get). This is arguably the most important step in the colour managed workflow because it is where you make important colour and quality decisions about your images.
If you are unable to differentiate all the steps or seeing a colour bias from the stepwedge above, then you are indeed a victim of bad monitor profiling or worse, a bad monitor.
The easiest and cheapest way to calibrate your display is by using software based tools in making adjustments to the brightness and contrast settings. On the Mac, you can use the Display Calibrator Assistant that comes with OSX. On Windows 7, you can access the Display Colour Calibrator via the Colour Management option in the Control Panel. Please note that these adjustment methods can be crude and inaccurate because they rely solely on eyeballing.
Mac OSX Display Calibrator Assistant
Windows 7 Display Colour Calibrator
In order to create an accurate and useful profile, a hardware device (colorimeter) is required. All commercial monitor calibration software lets you calibrate and characterize your monitor to a standard and then save the settings as an ICC-compliant profile available to your operating system and imaging applications. The most popular profiling solutions on the market today are:
Please note that before you invest in any software and hardware solution, make sure it can deal with both LCD and LED display technologies.
Before calibrating your monitor, ensure that you have a neutral gray desktop and your monitor has been warmed up for at least 45 minutes. Your ideal working environment should also have controlled and consistent viewing conditions with subdued neutral lighting.
(ISO 12646 Graphic Technology - Display for Colour Proofing - Characteristics and Viewing Conditions)
The frequency of your calibration routine depends on how often you use your monitor. At Crestock, we recommend calibrating your monitor at least once a month. Here are some quick reference settings for profiling:
Luminance (LCD): 120 cd/m2
Gamma 2.2
Colour Temperature: 6500˚K
The above settings are industry standard. Colour temperature of 6500˚Kelvin gives you a cooler and cleaner white and Gamma 2.2 delivers a better contrast. Luminance of 120 candela is a good starting point for most modern LED and LCD displays. The display luminance setting ultimately depends on your working environment. If you are working in a darker and more subdued environment, the luminance can be anywhere from 90 to 120 cd/m2.
Calibration Verification
Do not assume that every calibration is perfect. It is important to verify the quality of the calibrated monitor afterwards. The easiest way is to create a grayscale gradient in Photoshop for a quick visual check.
Good smooth gradient indicating good calibration
Problematic gradient (clipping and bands of colours) indicating poor calibration
An effective trick to enable consistent calibration is to have a reference image that you can refer to after each calibration process. You can construct a file that contains a grayscale stepwedge, colour gradient, colour swatches and skin tone. See the sample below.
As the above article indicated, having a monitor calibrated to the industry standard is an essential part of your complex digital colour workflow. Accurate on-screen colour ensures what you see on screen is what you get in printed media and on the web.