That idea was indeed my source, but in researching it turned out to be incomplete. I’ll just paste my response to that video cuz why not:
Good start, but you’re missing the fact that there are purple photons. The theory is that at the blue end of the spectrum, there are photons where the wavelength triggers blue cones, while a harmonic of the wavelength (specifically 2x the wavelength) triggers the red cones. You need a real rainbow in a controlled setting to see it, because camera sensors and film don’t respond the same way, so pictures usually don’t show it.
That then begs the question: What happens when add extra red? Does it become “more purple”? Because that would truly be an unreal color.
Edit: I guess the answer to that last bit is yes, it’s magenta.
