How Red is Red? A Brief History of Digital Color Re-creation

NanoLumens March 29, 2018 842 Views 0 Comments blog, Recent

There is only a certain range of colors that are perceptible and differentiable to the human eye. This visible color spectrum is something everyone is introduced to at a relatively young age when they first see the color wheel, but while the wheel is helpful for explaining the conceptual broad strokes of color spectrums, it isn’t quite as useful for objective, measurable purposes. To scientifically differentiate between different colors, you need to introduce math. This became a particularly relevant exercise when color was first integrated into digital display technology. Sure, display technology could reproduce the color red, but how red was it. Which red was it? To graphically represent the finite differences between colors, as it is most easily stated in layman’s terms, the International Commission on Illumination (CIE) created through a series of experiments a 2-dimensional graph that plots color based on chromaticity (a product of hue and saturation) on the X axis and brightness (also called luminance) on the Y axis. This was first created in 1931, and is thus commonly referred to as the CIE 1931 Chromaticity Diagram. The diagram, as seen below, graphically represents the visible color space.

Within the range of colors we can perceive, as plotted in the 1931 Diagram, there are smaller subsections of colors that digital displays can recreate. A meadow on a digital display doesn’t look the same as a meadow in real life, right? That’s because digital displays can’t quite show the same colors as real life. As mentioned above, because each display is built differently, each display is natively capable of recreating a slightly different subsection of the visible color space. In other words, their native color spaces vary. Content creators, most notably those involved in the television and film production industries, advocated for a standard gamut to be established so that colors would be displayed consistently across different technologies. This standard gamut was established in 1990, and dubbed Rec709. The 1931 Diagram below indicates the color space of Rec709.

As time went on and technologies improved, content creators demanded greater color space to show their work, so display manufacturers improved their technology to keep up. The newest standard gamut is called DCI-P3, and it was first published by the Society of Motion Picture and Television Engineers (SMPTE), of which NanoLumens is a member. DCI-P3 is wider and richer than Rec709, and is shown below.

NanoLumens displays are built with a native color space that is wider and richer than both Rec709 and DCI-P3. We are of course able to subsequently adapt our displays to meet either of these standards if so requested. Digital displays are getting better and better at recreating the colors of real life, and in doing so, they are pushing their native color spaces closer and closer to the limits of the visible color space. NanoLumens is at the forefront of this mission, and we hope one day to be able to show content indistinguishable from reality. To learn more about color and how it is used in digital displays, you can find further content on the subject here.