In their debrief of the December 2024 London seminar on metamerism hosted by Charles Poynton, the IMAGO Technical Committee shared a list of “potential solutions that were floated around the room.” Among them was this definitive directive:
“Stop chasing full Rec 2020 coverage as a physical target. Rec 2020 was established as a container format that can encompass the largest possible amount of colours without introducing any imaginary or illegal colours, but it was not necessarily meant as a target to physically achieve with any display.”
“established as a container format”. Masaoka’s correspondence, published papers and presentations show that BT.2020 was engineered as a forward-looking mastering color space, contingent on emerging emissive technologies. Masaoka anticipated a transition period where displays would gradually approach BT.2020 – not an indefinite “container-only” phase. The word “container” does not exist in the text of Recommendation ITU-R BT.2020 or BT.2100. The fact that it was later hijacked to use as a container for P3 does not change the original engineering intent.
“not necessarily meant as a target to physically achieve with any display”. That is flatly contradicted by the developer himself:
“One key intent behind BT.2020 was to define primaries that efficiently cover Pointer’s Gamut with three primaries… At the same time, BT.2020 was not meant to be purely theoretical in the sense of being only a container; practical realizability was also part of the thinking, especially for laser projectors and for displays using laser or other narrowband backlights. In fact, I built and evaluated prototypes along those lines, including comparisons of BT.2020 vs. P3 behavior in practice.”
—Dr. Kenichiro Masaoka, Principal Research Engineer at NHK, LinkedIn comment
Source: Metamerism Experts’ Day Debrief, IMAGO, Mar. 10, 2025
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