This reminds me of an experiment I've wanted to do for some time, but don't have the necessary equipment for. I'd love to see it tested by someone who do.
Take multiple light sources each shining in only one frequency, that can be dimmed, in specific triplets. Quickly eyeballing it I'd suggest [420nm, 550nm, 600nm] and [460nm, 500nm, 570nm]. using a normal white light source as a reference, first adjust the relative intensity of each triplet so the combined light appears white, then scale the combined light (probably by simply altering the distance) to the same intensity. Both lights should now appear identical. if they don't make further minor adjustments. Look at them side by side, until you can see the colour out of space. :)
rot13 hint url: UGGC://RA.JVXVCRQVN.BET/JVXV/SVYR:PBAR-ERFCBAFR.FIT
Why do you want to do this?
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