What are OKLCH colors?

It’s a “color” because it’s useful to describe such a thing. If you had monitor entirely filled with 50% white you’d call it white. Only by comparing it to something brighter do you call it gray. Brown is the same thing. In a dark room if you looked at a monitor filled with red and green pixels you’d call it orange. Only when you start adding in clues like whites and brighter colors would you call it brown.

Anyway, yes grey is a color. But it is not quite the same as other colors. Other colors occupy only parts of the visible electromagnetic spectrum. Whites are the whole thing.

There is actually several very good technology connections videos about this stuff. Color is very cool!

So, depending on what you're doing, you want different things. You may want to view your color space as an RGB cube, and go through gray. Or you may want to view your color space as something more like HLS or OKLCH, and not go through gray.

...with varying definitions of "whole". D65 white is almost blue when compared to A white. It stops being either “all the visible spectrum" or "in equal proportions” pretty quickly once you look closer at it.

Only if you're working with additive color.

With substractive, grey is just a darker (or dimmer) white.

I suppose that's different with light than some analog with pigments? (Two dabs of color set apart, a brush perhaps used to blend them as continuously as is possible.)

https://theconversation.com/how-rainbow-colour-maps-can-dist...

https://www.poynter.org/archive/2013/why-rainbow-colors-aren...

I think if you buy a tie-dye shirt or phone case and it comes out half grey, despite it being a valid color, most folks will be disappointed.

Aren't these in direct conflict? If you can't resaturate it, that implies it's not desaturated.

> I think if you buy a tie-dye shirt or phone case and it comes out half grey, despite it being a valid color, most folks will be disappointed.

And if you buy a forest motif, people will be upset if it's pink. That's just doing a tie-dye wrong, not a rebuke of whether it's a color at all.

Kinda. There's a singularity in the math. The problem is that hue is defined as an angle and saturation is defined as distance from the center, but there's no consistent way to define a direction for the origin. Black and white have the same problem because they're also desaturated.

> And if you buy a forest motif, people will be upset if it's pink. That's just doing a tie-dye wrong, not a rebuke of whether it's a color at all.

I'm not arguing that it's not a color, just that it doesn't belong in all gradients!

I thought the same until I googled "blue and orange tie-dye." I'll be honest, more white and black than I expected!

> So yes there are many answers but because it's not a quintessential example of a gradient.

We may have to agree to disagree that tie-dye isn't a quintessential example of a gradient. Would you argue that rainbows aren't either?

A magenta to green gradient would then go through white rather than grey. A subtractive magenta-green gradient would go through black. Not sure what physical setup would produce the latter gradient. But the standard RGB (or OKLAB) gradient goes through grey rather than white or black. This type of gradient is physically created by dithering: Dithering a gradient from magenta to green, by just using these two base colors, would produce a perceptual grey in the middle. This type of color mixing is otherwise better known as alpha blending.

Putting white or black in between adds another anchor point.

And looking more around examples of blue and orange tie dye, most aren't really gradients overall, they have big splotches of solid color with small gaps or overlaps in between, and at least half the time the gaps and overlaps don't even have a gradient inside them.

> We may have to agree to disagree that tie-dye isn't a quintessential example of a gradient. Would you argue that rainbows aren't either?

Hmm. How about this. I would say a rainbow is not a gradient between two colors, and the color space discussion is about a gradient between two colors. The exact border of "quintessential" is not something I really want to spend too much time on.