What Is Grayscale? A Basic Definition

Grayscale is a group of shades without any visible color. On a monitor, each pixel of a grayscale display carries an amount of light, ranging from the weakest amount of light, or black, to the strongest amount of light, or white. Grayscale only contains brightness information, not color.

On a computer display, images are composed of pixels, which are comprised of one red, one green and one blue dot. Each of these dots has its own brightness level as well and, therefore, can be converted to grayscale. A grayscale image is one with all color information removed.

What Is Grayscale Tracking?

When reviewing monitors, we show you grayscale tracking results. Grayscale tracking looks at a monitor’s ability to create the appropriate shade of white at all brightness levels. Good grayscale tracking means white is consistently neutral at all brightness levels. With the ideal grayscale tracking calibration, your monitor should display the white reference color (D65) at all brightness levels. Lower average Delta E values mean more accurate grayscale tracking.

Displays (even budget ones) usually have at least two sets of white balance RGB controls. Use them to manage the monitor’s white balance at a specific brightness level. This is also impacts your monitor’s performance with secondary colors cyan, magenta and yellow.

Here’s an example of a chart you’ll see on a typical monitor review on Tom’s Hardware. It shows you RGB (red, green and blue) levels at every level of brightness, from 0-100% (the X axis). A perfect result would have all RGB bars at the 100 line. If one bar is higher than the rest, that’s the color tint you’ll see at that brightness level if the Delta E value is greater than 3. 

The bottom half, the DeltaE 2000 graph, shows you how much error there is at each level of brightness, again from 0-100% brightness (the X axis). Generally speaking, errors below the yellow line (which represents a Delta E of 3) will not be visible to the naked eye. Therefore, this monitor has a green tint from 20-60% brightness. 

This article is part of the Tom's Hardware Glossary.

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Scharon Harding

Scharon Harding has a special affinity for gaming peripherals (especially monitors), laptops and virtual reality. Previously, she covered business technology, including hardware, software, cyber security, cloud and other IT happenings, at Channelnomics, with bylines at CRN UK.