A colorimeter is a color measurement instrument meant to assess color in a manner similar to how your eyes see color.
How Does a Colorimeter Work?
Display colorimeters perform “tristimulus” color measurement based upon light passing through Red, Green, and Blue filters, and then a sensor to produce colorimetric values like XYZ of L*a*b*. These values that can be used to calibrate a monitor – adjust the white point and contrast/gamma and then create an ICC profile.
Colorimeters vs Spectrophotometers
Colorimeters contrast with the generally more expensive spectrophotometer, which measures the full spectrum of color, not just RGB. While colorimeters are less expensive than spectrophotometers and take measurements more quickly, they also have limitations.
Just like your eyes can see color differently under different lighting conditions, colorimeters can also be “fooled” by different types of light sources. In the case of a monitor, the light source is the backlight. This is why colorimeter-based monitor calibration software asks you what type of backlight you are using, so the filters can be appropriately adjusted. Alas, how many people know what kind of backlight they are using?
Colorimeters vs TruHu
The TruHu monitor color calibration app works using principles similar to a colorimeter. It collects RAW RGB data from your camera’s sensors and then uses fancy math to generate colorimetric values.
One advantage of TruHu is it has a database of all commercially available monitors, including their respective backlight technology. Thus, TruHu automatically figures out the correct adjustments to make for a particular backlight instead of asking the user for information they may not have.
Additionally, the filters on colorimeters age over time and lose accuracy. The analog with your phone’s camera would be the lens. This is not a concern with TruHu, since the lenses do not degrade like RGB filters.
