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Current versions of LED streetlamps are absolutely awful. They have very high blue glare which is not only momentarily distracting in peripheral vision and disr

Current versions of LED streetlamps are absolutely awful. They have very high blue glare which is not only momentarily distracting in peripheral vision and disruptive of sleep cycles but also totally wrecks your night vision. It doesn’t help that they are often turned up to several times brighter than necessary. Same goes for LED car headlamps (especially on SUVs), which should be regulated right off the road. After San Francisco installed some awful LED lamps on my street, I’ve taken to wearing orange safety glasses when I walk my dog, and if I had to drive with any regularity I would consider wearing orange glasses to drive at night. The excuse I’ve heard that “these are the same color as moonlight” is total nonsense. We don’t have 10 moons hanging 20 feet off the ground on every city block. Nighttime is not supposed to look like daytime. People are not supposed to be reading novels in the street at night, or critically examining the colors of paintings. Moreover, much of the efficiency story is exaggerated. Recent types of high-pressure sodium lamps are very efficient. The big advantage LEDs have is that they (theoretically) don’t need to be replaced as often. We’ll see how it goes in practice over the coming decades. The real story of course is that lighting companies have made a big marketing push, and from what I understand there is state/federal grant money available for new LED lighting projects (which are sold as “environmentally friendly”, etc.). If cities want to use LED street lamps, they should be <3000K correlated color temperature, with as little blue light as possible. They should include diffusers, should be shielded to not shine in the eyes of pedestrians or drivers who aren’t intentionally looking upwards, should be spaced closely enough together that there isn’t a huge contrast between patches of dark and light going down the street, and should be set to a reasonable brightness. Human rod vision is incredibly adaptable to seeing in very dark situations.

Analemma_ 10y ago
This is mentioned in the article: the new streetlights are going to be at 3000K, between the 2200K of the sodium lamps and the 4000K of normal LED streetlights. It looks pretty good to me.
- jacobolus 10y ago
  3000K is still not great. I would prefer they cut the light from the blue diode entirely. But 3000K is much better than the 4000K version. “Color rendering index” is an absurd standard for nighttime lighting. (Not to mention a hacky ad-hoc metric from a few decades ago which is pretty terrible for any purpose, but that’s another story.) Someone should make a “night vision clobbering index” by which to judge the SPDs of outdoor lighting.
ams6110 10y ago
Blue spectrum's shorter wavelength makes it scatter readily and thus people experience glare and difficulty focusing on objects in blue much more than the red end of the spectrum. It's even worse in fog and rain.
- deleted 10y ago
  [deleted]
kingmanaz 10y ago
>If cities want to use LED street lamps, they should be <3000K correlated color temperature, with as little blue light as possible. Agreed that as "little blue as possible" is preferable, however, 1900K at high lumens should be the target, IMHO. Man is adapted to see at night via firelight and 1900K hits the mark. Actually performed this experiment at home... After having used clear bulbs for far too long, bought several of the following for our living room: http://www.verbatimlighting.com/prod/led-lighting/candle-led/vxrgb-true-candlelight-led-lamp/candle-led-sku-98423/ http://www.verbatimlighting.com/prod/led-lighting/candle-led... The "feel" of the room is entirely different, particularly when unwinding after work. "Cozy seat at the fireplace" best describes it. Our baby falls asleep gazing at the bare bulbs. Conversely, for the locals loitering to rap in our alley, bought a "clear" 150w mercury vapor fixture and bulb from e-Bay. Installed the light and even the cockroaches no longer venture into that eerie glow. If the mercury vapor alone doesn't solve the loitering issue, one can purposely damage the fixture's transformer so it produces an intolerable buzz. Perhaps the correct lighting depends on the situation.
- throwanem 10y ago
  For those not overjoyed at the idea of spending $22 per bulb, G7 Power makes [1] a low-color-temp bulb on an E12 base. I have several, in various accent lamps and nightlights, and they produce a pleasantly orange glow that's much warmer than the 2900K specification suggests. [1] https://www.amazon.com/gp/aw/d/B00CRHG63Y/ref=pd_aw_lpo_60_bs_tr_img_1?ie=UTF8&psc=1&refRID=CJ3D0G94MG5H4Z410FB0 https://www.amazon.com/gp/aw/d/B00CRHG63Y/ref=pd_aw_lpo_60_b...
zkms 10y ago
> Current versions of LED streetlamps are absolutely awful. Also they flicker too much -- a lot more than any other lighting source. It's utterly hateful and distracting, especially when you're driving or looking at a moving object. They also fuck up dark adaptation, which makes people materially unsafe. I want the best possible night vision when I'm out alone at night -- to better be able to detect, avoid, or defend myself against any sort of miscreant that might be hiding to ambush me. This is especially problematic because many of installations of outside lighting are done in order to provide better security, but if they're lights that dazzle and destroy dark adaptation -- this ends up being counterproductive.
- copperx 10y ago
  Do LED lights flicker more than fluorescent?
  - djaychela 10y ago
    I think if they're at the same frequency then they will appear to - the LED has a much sharper on/off curve than anything else. Certainly in one of the places I work they have new LED lights in the toilets and it's quite disconcerting as the strobing effect is noticeable. The LED lighting in the streets in my town (Bournemouth, UK) doesn't exhibit this, but certainly is very 'blue' at first, and my mother (who lives there) didn't realise the effect of the blue light in terms of sleep; she used to leave her curtains open at night and wasn't sleeping well. Closing them has helped greatly in that respect.
  - zkms 10y ago
    Yes. Good fluorescent bulbs will have electronic ballasts (the driving circuit) that supply current to the bulb with a higher frequency (in the low kilohertz) than the time response of the bulb's phosphor. Thus, any sort of flicker gets low-pass filtered and doesn't appear in the output light. Even with a subpar magnetic ballast that drives the bulb with line frequency, the phosphor never gets close to fully extinguishing -- so there is flicker, but the instantaneous light output never gets less than, say, half the maximum instantaneous light output. Look on page 3 of http://www.usailighting.com/stuff/contentmgr/files/1/e18f88d078a54622682528e496596192/misc/flickerfactsheet_doe.pdf http://www.usailighting.com/stuff/contentmgr/files/1/e18f88d... for some instantaneous light vs time graphs for fluorescent bulbs. LEDs have a much higher frequency response (in the tens of megahertz, easily) -- they respond quicker and more faithfully replicate their electrical drive signal as light output. You can see on page 4 of that report how violently jagged the LED's light/time plots can get. If the manufacturer didn't want to include filter capacitors in the LED's driver because of cost/reliability concerns, well, I hope your eyes enjoy that signal because the LED, unlike the fluorescent bulb, isn't going to smooth it out.
teslabox 10y ago
> After San Francisco installed some awful LED lamps on my street, I’ve taken to wearing orange safety glasses when I walk my dog, and if I had to drive with any regularity I would consider wearing orange glasses to drive at night. Thanks for the idea. I can't stand blue headlights, so I'm going to add orange safety goggles to my shopping list.

Analemma_ 10y ago

This is mentioned in the article: the new streetlights are going to be at 3000K, between the 2200K of the sodium lamps and the 4000K of normal LED streetlights. It looks pretty good to me.

jacobolus 10y ago
3000K is still not great. I would prefer they cut the light from the blue diode entirely. But 3000K is much better than the 4000K version. “Color rendering index” is an absurd standard for nighttime lighting. (Not to mention a hacky ad-hoc metric from a few decades ago which is pretty terrible for any purpose, but that’s another story.) Someone should make a “night vision clobbering index” by which to judge the SPDs of outdoor lighting.

ams6110 10y ago

Blue spectrum's shorter wavelength makes it scatter readily and thus people experience glare and difficulty focusing on objects in blue much more than the red end of the spectrum. It's even worse in fog and rain.

deleted 10y ago
[deleted]

kingmanaz 10y ago

>If cities want to use LED street lamps, they should be <3000K correlated color temperature, with as little blue light as possible. Agreed that as "little blue as possible" is preferable, however, 1900K at high lumens should be the target, IMHO. Man is adapted to see at night via firelight and 1900K hits the mark. Actually performed this experiment at home... After having used clear bulbs for far too long, bought several of the following for our living room: http://www.verbatimlighting.com/prod/led-lighting/candle-led/vxrgb-true-candlelight-led-lamp/candle-led-sku-98423/ http://www.verbatimlighting.com/prod/led-lighting/candle-led... The "feel" of the room is entirely different, particularly when unwinding after work. "Cozy seat at the fireplace" best describes it. Our baby falls asleep gazing at the bare bulbs. Conversely, for the locals loitering to rap in our alley, bought a "clear" 150w mercury vapor fixture and bulb from e-Bay. Installed the light and even the cockroaches no longer venture into that eerie glow. If the mercury vapor alone doesn't solve the loitering issue, one can purposely damage the fixture's transformer so it produces an intolerable buzz. Perhaps the correct lighting depends on the situation.

throwanem 10y ago
For those not overjoyed at the idea of spending $22 per bulb, G7 Power makes [1] a low-color-temp bulb on an E12 base. I have several, in various accent lamps and nightlights, and they produce a pleasantly orange glow that's much warmer than the 2900K specification suggests. [1] https://www.amazon.com/gp/aw/d/B00CRHG63Y/ref=pd_aw_lpo_60_bs_tr_img_1?ie=UTF8&psc=1&refRID=CJ3D0G94MG5H4Z410FB0 https://www.amazon.com/gp/aw/d/B00CRHG63Y/ref=pd_aw_lpo_60_b...

zkms 10y ago

> Current versions of LED streetlamps are absolutely awful. Also they flicker too much -- a lot more than any other lighting source. It's utterly hateful and distracting, especially when you're driving or looking at a moving object. They also fuck up dark adaptation, which makes people materially unsafe. I want the best possible night vision when I'm out alone at night -- to better be able to detect, avoid, or defend myself against any sort of miscreant that might be hiding to ambush me. This is especially problematic because many of installations of outside lighting are done in order to provide better security, but if they're lights that dazzle and destroy dark adaptation -- this ends up being counterproductive.

copperx 10y ago
Do LED lights flicker more than fluorescent?
- djaychela 10y ago
  I think if they're at the same frequency then they will appear to - the LED has a much sharper on/off curve than anything else. Certainly in one of the places I work they have new LED lights in the toilets and it's quite disconcerting as the strobing effect is noticeable. The LED lighting in the streets in my town (Bournemouth, UK) doesn't exhibit this, but certainly is very 'blue' at first, and my mother (who lives there) didn't realise the effect of the blue light in terms of sleep; she used to leave her curtains open at night and wasn't sleeping well. Closing them has helped greatly in that respect.
- zkms 10y ago
  Yes. Good fluorescent bulbs will have electronic ballasts (the driving circuit) that supply current to the bulb with a higher frequency (in the low kilohertz) than the time response of the bulb's phosphor. Thus, any sort of flicker gets low-pass filtered and doesn't appear in the output light. Even with a subpar magnetic ballast that drives the bulb with line frequency, the phosphor never gets close to fully extinguishing -- so there is flicker, but the instantaneous light output never gets less than, say, half the maximum instantaneous light output. Look on page 3 of http://www.usailighting.com/stuff/contentmgr/files/1/e18f88d078a54622682528e496596192/misc/flickerfactsheet_doe.pdf http://www.usailighting.com/stuff/contentmgr/files/1/e18f88d... for some instantaneous light vs time graphs for fluorescent bulbs. LEDs have a much higher frequency response (in the tens of megahertz, easily) -- they respond quicker and more faithfully replicate their electrical drive signal as light output. You can see on page 4 of that report how violently jagged the LED's light/time plots can get. If the manufacturer didn't want to include filter capacitors in the LED's driver because of cost/reliability concerns, well, I hope your eyes enjoy that signal because the LED, unlike the fluorescent bulb, isn't going to smooth it out.

teslabox 10y ago

> After San Francisco installed some awful LED lamps on my street, I’ve taken to wearing orange safety glasses when I walk my dog, and if I had to drive with any regularity I would consider wearing orange glasses to drive at night. Thanks for the idea. I can't stand blue headlights, so I'm going to add orange safety goggles to my shopping list.