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Some cities are taking another look at LED lighting after AMA warning

washingtonpost.com

71–80 of 108 posts

Re: Some cities are taking another look at LED lighting after AMA warning

#71
I had LEDs installed in the streetlight in front of my apartment in Brooklyn a few months ago and my living room is now awash with this light. It's terrible. I noticed my sleep time pushed further and further back and I've resorted to supplementing melatonin regularly so that I can fall asleep earlier than 2 am. I've complained to the city and have considered moving since I don't think NYC will swap ours back.

Re: Some cities are taking another look at LED lighting after AMA warning

#72

Earlier quoted context omitted.

What temperature LED light should I have for my bedroom?

Essentially any LED bulb that you can buy is a blue diode with a down conversion phosphor. The composition of the phosphor, and the relative amount of blue light vs. phosphor emissions shape our perception of color temperature for these LED sources. Due to an effect called metamerism, our brains can perceive the same apparent color from sources with different underlying spectral power distributions (power vs. wavelen…

Some LEDs have phosphors which almost entirely absorb the light from the diode.

Re: Some cities are taking another look at LED lighting after AMA warning

#74
post #64

I'm not sure what the point was in the first place? Sodium lamps approach 200 lumens/watt. LEDs are whiter, but whiter light doesn't necessarily help you drive, does it? If the concern is colored signs, light the signs?

Big point #1 was federal subsidies and big new contracts for lighting vendors.

Big point #2 (an actual advantage now) is reduced maintenance cost because the lamps (theoretically) last longer between replacements.

The energy efficiency claims were always a red herring.

Re: Some cities are taking another look at LED lighting after AMA warning

#75
post #62

Earlier quoted context omitted.

This is an obnoxiously dismissive comment build on ignorance and shoddy reasoning and an “I don’t care what you think just suck it up and stop complaining” approach to design/policy. The moon is one (1) singular source of light with a known peak intensity, often blocked by trees or clouds, and only at its brightest one day every month. On a full moon night, the moon is high overhead, not directly in your field of vie…

Yes, I was a little glib. But nonetheless life on Earth (not just our species) evolved with a 4100K light source at night. You are confusing color temperature with how the lights are installed. If your streetlights were 4000K and spaced properly you wouldn't have an issue with them. The penny-pinching distribution (high lumens, wide angle, distantly spaced) of lights chosen by your city is at fault. That layout will…

> ... evolved with a 4100K light source at night

As others have noted, we sleep poorly under strong moonlight.

I live in a very rural wooded area, and I can leave my blinds open except when the moon is at its brightest -- I sleep very poorly if I don't use blackout curtains.

Perhaps the fittest humans were the ones who stayed the most awake and aware of nocturnal predators during the brightest nights of the month?

Re: Some cities are taking another look at LED lighting after AMA warning

#76

I had LEDs installed in the streetlight in front of my apartment in Brooklyn a few months ago and my living room is now awash with this light. It's terrible. I noticed my sleep time pushed further and further back and I've resorted to supplementing melatonin regularly so that I can fall asleep earlier than 2 am. I've complained to the city and have considered moving since I don't think NYC will swap ours back.

Please, put in blinds. If you have blinds, put in curtains to catch the light that spills around the blinds. If too much light goes through the blinds, upgrade to window shades. If that isn't enough (or you don't want to spend any money on interior decorating), get an eyemask. If $2 for an eyemask is too much, drape a t-shirt over your eyes.

Moving is a comically inappropriate response.

Re: Some cities are taking another look at LED lighting after AMA warning

#78
post #33

Earlier quoted context omitted.

You're thinking of 'promoting wakefullness' like a cup of coffee that has an immediate effect that wears off when it leaves your system. 'Disturbing sleep' means they alter your hormone production & release, which is something that begins to affect you over weeks and months. High color temperature lights disturb sleep- without promoting wakefullnes.

The light has an effect during the night as it blocks the melatonin hormone from kicking in. It takes about an hour of darkness for the hormone kick in and make you sleepy. On very long occasional drives it's probably safer to trade some sleep disturbance for a more wakeful drive. If it's your daily commute it'll probably mess up your sleep.

And if it's on your residential block, it'll definitely mess with your sleep.

Re: Some cities are taking another look at LED lighting after AMA warning

#79

Earlier quoted context omitted.

Essentially any LED bulb that you can buy is a blue diode with a down conversion phosphor. The composition of the phosphor, and the relative amount of blue light vs. phosphor emissions shape our perception of color temperature for these LED sources. Due to an effect called metamerism, our brains can perceive the same apparent color from sources with different underlying spectral power distributions (power vs. wavelen…

Some LEDs have phosphors which almost entirely absorb the light from the diode.

For example, Lumileds PC Amber and Lime LEDs employ this trick. They're usually used as a corrective color component and not the main lumen source.

Re: Some cities are taking another look at LED lighting after AMA warning

#80
It is a confusing story, and not well supported by actual facts or studies. So I wonder about these things, who has it in for street lights? Crooks obviously it makes their life harder (and it mentions in the article that police are getting better witness descriptions under LED lights). And presumably the folks who made the old Mercury Vapor lights. Which happen to have about 1/10th the cost to make as LED lights but seem to sell for the same amount, so perhaps their margins are getting squeezed uncomfortably. Power companies of course, who could depend on the electricity load coming from inefficient street lights finding that one of their biggest consumer at their lowest utilization time is cutting their power requirements by 33% or more. That has to hurt you really don't want to turn off base load during the night. And of course people who liked the look of their street before and now are sad because it looks different[1].

[1] When people switched from coal fireplaces to gas heat a common complaint was that it didn't smell like home any more.

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