[zokier]

> And many people know that specific colors are really just wavelengths in the electromagnetic spectrum. [...]

> There are many systems involved to turn an RGB triplet value into a specific wavelength of light

I think this wavelenght-color connection, often perpetuated in high-school classrooms, confuses people more than helps. In particular when talking RGB colors, your display (or really, any part of the process) will not really change the wavelenghts of outputted light based on the input.

Also colors really are not just wavelengths in EM spectrum. Color is more of a perceptual phenomenon, something that happens in our heads, more than physical phenomenon. And there are many things that can impact the color perception, most obviously the other surrounding colors and ambient lighting.

[JJMcJ]

https://hirund.in/blog/magenta-doesnt-exist

Paradoxical title - for the notion that magenta is something we perceive, not a wavelength.

An example of https://en.wikipedia.org/wiki/Spectral_color#Extra-spectral_...

[vlovich123]

That’s when you’re talking about color production (how the artist/content creator intends a specific visual image to be perceived).

Color reproduction is 100% an engineering thing about wavelengths. To my knowledge monitors do indeed change the wavelength. Sure it’s several separate colored emitters, but using constructive and destructive interference to generate a wavelength doesn’t take anything away from it.

There are places where things get messy where reproduction blends in a bit of production (eg applying an HDR filter, applying monitor-specific tweaks, etc). It’s a complex topic for sure. But the position of “color is purely a perception in our head and not wavelengths” position is too extreme in the opposite direction and isn’t helpful in building things.

[willis936]

No. Displays make (relatively) sharp peak emissions at one wavelength. We blend their relative intensities to trick our mind into thinking it's seeing the wavelength in between those three spectral peaks. All the colors we can see are from the spectral response of our three cones (hence why we use three spectral emission lines). We simply cannot tell the difference between magenta and red+blue. The actual photons are not interacting with each other. Take a prism to your display and you'll see the discrete emissions. This wouldn't happen with an actual magenta emission (which also doesn't exist, further highlighting the limits of color in the human vision system).

https://en.wikipedia.org/wiki/Cone_cell

[mncharity]

> Displays make (relatively) sharp peak emissions at one wavelength.

Even microLED spikes are tens of nm wide.[1] Calling that "one wavelength" seems problematic, given all the confusion here today, and in TFA, between wavelength and spectrum and perceptual color.

[1] https://www.researchgate.net/figure/a-Measured-RGB-red-green...

[bildung]

> It’s a complex topic for sure. But the position of “color is purely a perception in our head and not wavelengths” position is too extreme in the opposite direction and isn’t helpful in building things.

As an illustration for the in your head position: Human eyes can't directly perceive yellow tones. What we think of as yellow is a computation on the signals of both the M and L cones. If both say they perceived radiation at approx. the same intensity, that gets calculated as yellow afterwards.

That's why RGB displays are not reproducing the correct wavelengths, but only those our eyes can read directly: red, green and blue.