Reply to post: Re: Light preference

White LED lies: It's great, but Nobel physics prize-winning great?

Nigel 11

Re: Light preference

It's not the brightness, it's the full spectrum. You can see far better with N lumens of light from an incandescent source, than the same N lumens from a fluorescent source.

The spectrum of a CFL is quite frightful. A white LED is considerably better, but there's still far too much blue in it. Our eyes are evolved to see best with an incandescent source (the sun, a flame) or smoothly filtered derivations (moonlight, the setting sun). An old-style lightbulb may well activate psychological / physiological responses associated with sunset - hence "cosy". (My opinion of LEDs is that they are "brighter" than daylight, and therefore quite unsuitable for night-time illumination).

There's also a gathering body of evidence that even very low levels of blue light can disrupt sleep patterns. If you have any sleep trouble and LED lighting I'd suggest getting some red- or amber-LED torches and nightlights, and avoiding ever turning on white LEDs between bed-time and morning. Also put black tape over any blue LEDs on electronics in your bedroom.

I suffer from mild SAD so I notice these things more than many. White LEDs are good for waking up on dark mornings!

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