Re:A call to improve London's lighting at night
by colechristensen on Thursday March 18, 2021 @12:42PM
(#26504565)
I'm happy sodium lamps are getting replaced, I'm not happy with the replacements which might be worse.
With LEDs it should be very possible to light streets with low temperature close-to-blackbody light. (I don't know if the proximity to a blackbody radiation distribution is the same as CRI etc.) Who wouldn't want this?
Re:A call to improve London's lighting at night
by ben_w on Thursday March 18, 2021 @04:11PM
(#26507049)
LED light can be about as far as it’s possible to get from a blackbody spectrum, if similarly to that is what you care about (I don’t, art galleries do).
There are two ways of doing “white” with LEDs:
• Separate red, green, and blue, whose spectrum is spiky: https://en.wikipedia.org/wiki/Light-emitting_diode#/media/Fi...
• Phosphor, which may give you a spectrum like this: https://en.wikipedia.org/wiki/Light-emitting_diode#/media/Fi...
Re:A call to improve London's lighting at night
by jeffbee on Thursday March 18, 2021 @10:55AM
(#26503326)
CRI is not used to measure whether a light helps people with practical vision tasks at night. It’s quite possible that a light with CRI zero, totally monochromatic, could be the best choice by some objective measures.
Re:A call to improve London's lighting at night
by ClumsyPilot on Thursday March 18, 2021 @05:55PM
(#26507976)
If CRI is low, all colours on an object are fucked. Ao people in general are going to be worse at idebtifying what they are looking at or reacting. You won't be able to look at a picture, read text on your credit card, etc.
Sure what you outline is possible in some spesific scenario, but it's not gonna work for 99%
I think it is neither "natural" or better illuminating. Sodium lamps have CRI of around, what, 30?
I'm glad that these sodium lamps are finally getting replaced everywhere, and cities at night won't have that monochromatic depressing-ugly-yellow lighting.