It assumes basic knowledge of the spectrum of various light sources. All white LEDs have a spike in the blue spectrum that incandescents don't: https://www.rese

It assumes basic knowledge of the spectrum of various light sources. All white LEDs have a spike in the blue spectrum that incandescents don't: https://www.researchgate.net/figure/Spectrum-of-a-white-LED-clearly-showing-blue-light-which-is-directly-emitted-by-the_fig2_200071029 https://www.researchgate.net/figure/Spectrum-of-a-white-LED-...