The perceived vibrancy of a display is not only dependent on the spectrum of light emitted but also on the way the colors of an image are mapped to the colors of the display. Better understanding of color would help with the latter.

Marketing really wanted a game winning solution. One thing I learned - no two sets of eyes are the same - at an extreme 10% of the male population are red-green color blind but in reality we're just not all the same - there is just no perfect color matching solution

This is especially frustrating with photography. No two people see a single scene the same way; the best you can do is take raw data and interpret it into the tiny, tiny display space the way you think best describes the scene. Yet do many think that the blandest possible JPEG render is the reference truth of what reality is actually like.

You're most likely correct, that is for current display technologies. For years, I've hypothesized that we cannot solve the problem with tricolor displays and I've postulated that we need a 7-color system to do proper justice to our eyes/perception and even then it'd still be an approximation albeit a pretty good one.

Obviously, I can't argue this out here or we'd be at it for weeks. Suffice to say I'm far from being alone in thinking this way.

Keep your ears to the ground and no doubt you'll soon hear from better minds than mine on the subject.

The challenges however for any new color system are formable and it would require new developments in technology before being practical.

The human eye is quite remarkable, it adapts dynamically to the situation in both its luminance and chrominance channels and has an effective dynamic luminance range of around 10^6 : 1.

To give you a sense of how truly adaptable the eye is here's an example: the now defunct Kodachrome - which was once the gold standard in film emulsions and in some limited ways still is - only had a luminance dynamic range of between about 250 and 500 : 1 (depending on how you measure it, 250 being more the norm), and its chromaticity was pretty limited especially in reproducing violet (violet being the least objectionable tradeoff) and yet it was capable of producing some quite wonderful photographs (and I've still many thousands of slides to prove the fact).

Now if you compare Kodachrome with what the eye is actually capable of then there's essentially no comparison, Kodachrome falls so far short you'd wonder why we'd bother using it at all. The fact is the eye adapts to that limited situation and does a remarkable job of fooling you into believing that the Kodachrome image is the 'true and real thing'.

This example also illustrates the very real difficulties in getting to the bottom of color theory. Keep in mind the issues here: real light consists of an almost continuous electromagnetic spectrum, the eye resolves this by matrixing RGB primaries to produce an 'imaginary' spectrum and it also has to deal with extra-spectral colors such as magenta, and there are other issues as well.

As I hinted I'm reticent about entering a heavy debate about this subject here as I can only do so superficially - just one word out of place and it'll be mistaken as wrong and it'd only derail the debate.

Look, it's a huge subject: (a) our existing color technologies - video/television, printing and color film - are already very sophisticated and are full engineering professions in their own right - and as we're discussing all have quite severe limitations in their ability to faithfully reproduce the luminance channel let alone the chrominance one, and (b) the theory of color vision is not only complex and quite difficult to understand - and now it's become even more complex.

I will however finish with an idea I've had for years that could overcome many of the limitations of the tricolor (or any multicolor system). It's completely theoretical as the tech still doesn't exist. The idea would work like wideband superhetrodyne radio receiver. A UV laser as the local oscillator would beat with incoming light in a mixer to produce an IF (intermediate frequencies). The more manageable IF would be bandwidth compressed and eventually reconverted up-band to visible light so the viewer is actually seeing a spectrum of visible light. Simply, a TV camera of such system would capture say light at 555nm and that's what the viewer would eventually see - and not some mixture of RGB primaries. Picking coordinates on the CIE would be a thing of the past.

Now, I know the objections will be many and all sorts of issues both technical and theoretical arise but there's little point in debating them here.

I've raised this for one reason. The whole problem we have with color reproduction starts with the fact that we cannot reproduce the eye's CIE with true accuracy and using any number of CIE coordinates will never completely solve the problem.

Eventually, we need to find a better way. Finding a way to accurately record the incoming wavelength of light in recorded images would also provide us with many other scientific and engineering advantages.

> At the end of the day, colors -- whether in a movie scene or a paint chip -- are ultimately chosen by eye, not by math

Well.... math is involved if you want to do even simple stuff like blending two colors in a paint program. There is subjective stuff, sure, but you aren't going to get very far in computer graphics, display manufacture or camera chip manufacture, if you just conclude that it is 100% subjective and there is no mathematical logic behind it.

The same can be said about all human perception in general, not just colors. Artists exploit this for centuries, and are trying to formalize this. Newer color appearance models try to precisely quantify perception effects to make better color appearance possible.

I'm not sure how to explain why further than that, it's not even wrong, something I've definitely seen is the more people know about color, the more complex it seems when usually it's more simple when you start thinking across reference frames / viewing conditions

Source: builds color spaces using color appearance models

Rendering to the display device screen uses perceptual intent: a conversion of color space of the display under some assumptions about screen viewing environment etc. [1]

With better models we can improve this conversion. Article mentions that large color differences are not perceived as acute as the current models (Riemman etc) suggested so new model could boost the color difference to achieve that higher acuity.

[1] https://blog.colorgate.com/en/rendering-intent-explained

Mental model for color space that keeps things on track is it's just like any 3D space. Here, we could say "distance space" like "color space" and two "distance spaces" are miles and kilometers, (two color spaces are RGB and $ONE_FOLLOWING_FROM_PAPER)

If we found the distance equation in distance space differed from expectations, due to interesting things about physical geometry, that wouldn't create new places.

Why? The map is not the territory. The physical space still exists as it did.

Moving from distance to color: the physical display gamut is the territory. The map is the color space.

If we discover our distance metric in the space is flawed, we'd measure distance between colors as different than before. That wouldn't create new colors in color space.

Source: I create color spaces

like given two renders of the same image with different metamer selections, are there possibly subconscious impacts to mood or feeling between them. do different spectral envelopes that produce the same percept result in different demands or representations in the ventral stream which then could (or may not) manifest in nonobvious ways?

i was under the false impression that the transfer function for each group of cones was a function of some processing in higher layers of the ventral stream.