Why does the chromaticity diagram look like that?

That particular version of the chromaticity diagram makes it look like the colors missing from your display are various shades of laser pointer green as opposed to all the shades of red and blue that are missing because really saturated red and blue primaries are too dim (per unit of energy) to use.

See https://nanosys.com/blog-archive/2012/08/14/color-space-conf...

I learned a lot more about color management than I wanted to know in the progress of making red-cyan stereograms because I found when I asked for sRGB red I was getting something like (180,16,16) on my high gamut monitor which resulted in serious crosstalk between the channels.

Right now I am working with a seamstress friend on custom printed fabrics and I have a flower print where yellow somehow turned to orange in the midst of processing the image and I want to get it debugged and thoroughly proofed before I send out the order... I am still learning more than I want to know about color management.

>Right now I am working with a seamstress friend on custom printed fabrics and I have a flower print where yellow somehow turned to orange in the midst of processing the image

That's why Pantone makes so much money.

> as opposed to all the shades of red and blue that are missing because really saturated red and blue primaries are too dim (per unit of energy) to use.

Would another way to put that be, that the chromaticity diagram could keep going southeastward (i.e. the XYZ color-space could have the X and Z activation functions extended leftward and rightward), but due to the frequencies continuing on the spectral line, that area of the diagram would necessarily be made mostly of infrared and ultraviolet frequencies that we can't see?

And, importantly, that's why Pantone isn't just a freeloader making money off of nothing the way that some of the more clickbaity parts of the internet represent them. They're not solving an easy problem, if they were they wouldn't get paid.

Aren’t they (present humans) simply profiting from work done decades ago (past humans, not them) through patents or others kinds of IP / protections granted by governments ? Surely it was original and useful before but now it’s part of humans knowledge base

They solve a very real problem with most of their products. Universal physical references and supplies are great.

But charging for the libraries that list a basic sRGB or CMYK code for each Pantone color is a pain in the ass leech.

Somewhat, but that work has utility to this day. You can find competing products out there if you don't want to pay Pantone's rates, but there's a reason many people still work with Pantone. It's a universal language of sorts.

https://www.culturehustleusa.com/products/freetonebook

From your linked article:

>The colored region of the plot, labeled "visible region", contains points in the space representing colors humans can see, while the non-colored region contains points representing physically impossible cone stimulations.

Visual perception goes way way way beyond just what the eyes' cones can physically see — you've got an entire brain back there trying to interpret optical nerve phenomena!

For a nice brain tickler, look up physically impossible to conically detect Chimerical Colors (e.g. stygian blue; self-luminous red; hyperbolic orange), which can be seen without actually having been seen †

†: https://www.perplexity.ai/search/please-provide-chimerical-c...

W: https://en.wikipedia.org/wiki/Impossible_color

> Right now I am working on custom printed fabrics

You almost certainly need to work in the vendor's CMYK/SWOPv2 color space profile to get the colors to come out right. Ask them. Saturated RGB doesn't convert well. Plan B: desaturate to a slightly grayish yellow.

One example: https://ctnbee.com/en/upload

What defines them as "leeches" or not is if they keep adding value to their work.

Passively profiting from some work done decades ago makes them something you want to destroy; increasingly improving their catalogue with valuable new tones and knowledge makes them something you want to protect.

The vendor specifies sRGB so sRGB it is. For that matter my Epson printer specifies a native color space which is basically RGB, I wish I could tell it to lay down various amounts of C, Y, M and K pigments I can't.

I have the real object to compare with the screen and with paper and fabric prints under various viewing conditions. I am going to print small samples, order a set of RGB labeled color swatches, etc. I have to tighten up my whole chain because I have a wide gamut monitor and also produce Display P3 for social sharing and would like to prototype realistically on my inkjet.

Pantone is not the immediate answer to my problem because my image is photographic. Pantone's strength is that you can mix a few colorants from a library to make a number of precise spot colors many of which can't be rendered in CYMK. It has dayglo, metallic and all sorts of amazing things.

My vendor (Spoonflower) takes sRGB and will sell me a set of color swatches with hex code labels that I can use, like the Pantone book, to calibrate color by eye or colorimeter, etc.

Spoonflower will give me a %10 commission if somebody buys my product in their marketplace, but the product is expensive, a luxurious fabric that costs $20 a yard costs upwards of $50 if it is inkjet printed. For all this the only material investment is proofing, prototyping and showpiece production.

If I really wanted to make money though I could find another vendor who, I think, could set up a run of 10,000 yards on an offset lithography press. The litho process is more tolerant than inkjet so the shop can mix up Pantone colors as spots.

My photo is mostly monochromatic and might come across well in spot color so it might be a choice to pick a color I like out of the Pantone book if I was working with a larger run print shop. Problem is I'd have to put up quite a bit of money and then warehouse the stuff and be really certain people will buy it or I can make something out of it.

My photo is monochromatic and might do OK if I thought a Pantone chip was close to the object color I could do it in spot but this time I'm going to do it by sRGB chips.