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Doctors issue warning about effects of LED streetlights on health

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Re: Doctors issue warning about effects of LED streetlights on health

#71

Post by 5555624 »

steveax wrote: post #38
NetTechM wrote: post #14

I would argue that people with those crazy LED headlights are even worse. Since I often work late, I get the pleasure of being temporarily blinded as a white dwarf passes by at 45mph regularly.

And don't even get me started on the LED eye melters that cyclists are running these days. Some are about as bright as car headlights, but the spread and aim are inferior - especially since the folks that run those invariably seem to point them up from the horizontal. I keep thinking about mounting a 8 D cell maglight on a gimbal on my handlebars to give them a photon in-kind response.

More often than not, they're not mounted correctly. When it comes to headlights, too many cyclists (most?) do not think of their bike as a vehicle. The headlight should be a solid light and the light beam should not be parallel to the ground. the primary purpose of your headlight is there to help you see where you're going. If it's not, you don't really ride in the dark. As with any other vehicle, being seen is a secondary reason for lights.

I've been commuting by bike, year-round, for 17 years. While my commute home may require lights, my morning commute requires them. (It's at 3:00 a.m. and some stretches have no lights.) If my headlight was parallel to the ground, it would not let me see where I am going. Oh, it will show a person or vehicle, but it won't let me see the road. It's aimed at a spot X feet in front of me, enabling me to see debris on the road, as well as anything huge.

Properly aimed or not, a headlight is only going to let a motorist (or anyone) see you if they are coming towards you. I can see them coming, too. A good reflective vest and secondary lights (helmet, side, etc.) is necessary to let people see you from behind or the side. (The vest is useless if the car is running without its headlights on, which has happened to me a few times in the morning.)

Re: Doctors issue warning about effects of LED streetlights on health

#73

Post by jhanschoo »

Laforet wrote: post #58
stormbeta wrote: post #33

Earlier quoted context omitted.

True, but there's a real problem with people and places using lights with far too high a temperature, and even when shopping for home LED lights it's surprisingly difficult to find low temperature lights that aren't low on lumens output. Pretty much anything over 3000K looks horribly blue at night, and if it wasn't such a massive pain to find them I'd prefer <2000K.

I have a bigger issue with fluorescent lights: They have a discontinuous spectrum[0] that can mess with your perception of colour as well as a noticable flicker that gets worse as the tubes age. Some of the newer "warm tone" CFL bulbs appears to do better better on these aspects. [0]: http://minerva.union.edu/newmanj/Physics100/Light%20Producti...

Don't LEDs have a similar (or worse) spectral profile?

Re: Doctors issue warning about effects of LED streetlights on health

#74

Post by Mithaldu »

sgarman wrote: post #57
steveax wrote: post #38

Earlier quoted context omitted.

And don't even get me started on the LED eye melters that cyclists are running these days. Some are about as bright as car headlights, but the spread and aim are inferior - especially since the folks that run those invariably seem to point them up from the horizontal. I keep thinking about mounting a 8 D cell maglight on a gimbal on my handlebars to give them a photon in-kind response.

If you see the biker then I think the lights did a good job. I suppose you could make an argument that it could blind people and they hit someone/something but I never heard of that happing - I only hear bikers getting hit because they were not seen.

> the lights did a good job

No, absolutely not.

Lights are to help the cyclist SEE.

To be SEEN you need reflectors. [1]

Worse, if a cyclist's frontlight is blinding other cyclists coming at him it means they're failing both the others AND themselves, as: The oncoming ones can't see shit and are more likely to make a mistake and the rider themselves isn't illuminating the ground ahead of them so they can't actually see where they're going.

[1] https://www.youtube.com/watch?v=CfWzeGlaFvI

Re: Doctors issue warning about effects of LED streetlights on health

#75

Post by cauterized »

mullingitover wrote: post #22
cauterized wrote: post #19

Earlier quoted context omitted.

Surely then we could use blue-white LEDs on highways an in commercial areas where most of the driving time is spent and warmer colors in residential areas that are just the last minute or two of the drive and are where people are trying to sleep?

That seems like the right answer to me. I still think the streetlights make very little difference compared to the time that the average person spends looking at a screen, however. In my experience the only time I'm looking at streetlights are when I'm in a car, or walking to one. On the other hand I probably average three hours a night looking at a screen.

For those of us who have LED streetlights right outside our bedroom windows, it makes an enormous difference relative to screens, most of which these days you can at least put into an after-sunset mode even if you don't just voluntarily turn them off. The streetlights are on all night and they don't have an off switch.

Re: Doctors issue warning about effects of LED streetlights on health

#76

Post by sevensor »

Blue indicator LEDs on consumer electronics are a real plague. I had to cover the LEDs on a noise machine with electrical tape because of the harsh blue glow. I had to wonder what on earth the manufacturer was thinking -- this product is marketed to parents of newborns to help their babies sleep! Heartbeats, whalesong, blinding blue LEDs, white noise: one of these does not belong.

Re: Doctors issue warning about effects of LED streetlights on health

#78

Post by cauterized »

dingaling wrote: post #49
siegecraft wrote: post #9

Earlier quoted context omitted.

Yes, but daylight only occurs during the day, hence the name.

> Yes, but daylight only occurs during the day, hence the name. Only because for more than a century the overwhelming majority of domestic light bulbs aped the colour temperature of candles, so that nightlight unconsciously became associated with yellowness. There's nothing inherently 'right' about warm yellow light, it's entirely subjective based upon conditioning. For example people in hot, arid climates describe b…

And for eons before that, the light we had at night was fire. That's long enough for us to evolve to be sensitive to blue light as a signal of daytime while having decreased curcadian sensitivity to light at lower color temperatures.

Re: Doctors issue warning about effects of LED streetlights on health

#79

Post by jhayward »

NetTechM wrote: post #14

I would argue that people with those crazy LED headlights are even worse. Since I often work late, I get the pleasure of being temporarily blinded as a white dwarf passes by at 45mph regularly.

Most of the offending lights, as far as I know, are badly done retrofit kits that don't have the proper focusing hardware. Owners and cheap shops just drop an LED replacement into a "standard" headlight reflector and get horrible results.

The proper ones, like one sees on BMW, etc., don't blind people.

Re: Doctors issue warning about effects of LED streetlights on health

#80

Post by frabbit »

5555624 wrote: post #71
steveax wrote: post #38

Earlier quoted context omitted.

And don't even get me started on the LED eye melters that cyclists are running these days. Some are about as bright as car headlights, but the spread and aim are inferior - especially since the folks that run those invariably seem to point them up from the horizontal. I keep thinking about mounting a 8 D cell maglight on a gimbal on my handlebars to give them a photon in-kind response.

More often than not, they're not mounted correctly. When it comes to headlights, too many cyclists (most?) do not think of their bike as a vehicle. The headlight should be a solid light and the light beam should not be parallel to the ground. the primary purpose of your headlight is there to help you see where you're going. If it's not, you don't really ride in the dark. As with any other vehicle, being seen is a sec…

> the primary purpose of your headlight is there to help you see where you're going.

Sorry. Didn't see you.

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