6 ms·

LEDs’ potential to save our night skies

249 points by defrost 3mo ago

jacooper 3mo ago
I would 100% rather have a truly bright and lively city at night than a visible night sky. More than half the year is in the winter ffs!
dgellow 3mo ago
> Thorp notes that modern CCTV cameras are “pretty great” even at low-light levels, while harsh light makes it hard for both human eyes and digital sensors to see. That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system”
- WarmWash 3mo ago
  Their prime audience for change are governments...
- swiftcoder 3mo ago
  > That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system” One of the biggest excuses for ultra-bright streetlights is crime prevention (usually shortly followed by CCTV). I'm not really sure why we continue to indulge that point of view, but if one is indulging it...
  - rznicolet 3mo ago
    It's even funnier that, at least around here, one of the biggest crime problems is people stealing copper wiring... from streetlights...
  - trollbridge 3mo ago
    The "lights=safety" nonsense shows no sign of coming to an end. Many private residences also install eye-searing levels of lighting outside that they just leave on all night, which is much cheaper to do now thanks to LED technology. There's really no reason for doing it. The idea it deters crime is a long-standing myth (someone analogous to the idea CCTVs deter crime).
  - Jblx2 3mo ago
    I know we can be all righteous and intellectual on HN. But the article pretty much glosses over the large number of people who are afraid of the dark. Not afraid of crime in the dark. Actual adults who are apparently having a visceral reaction to the dark. What percentage of people is this? What percentage of those would adapt in a positive manner?
    - swiftcoder 3mo ago
      Those people can carry around a cheap LED lamp if it so pleases them...
- mghackerlady 3mo ago
  Even then, couldn't you just use IR cameras with IR lights for illumination. I'm sure that comes with it's own set of issues, but strictly speaking is better for maximising surveillance while minimising human impact
- pjl0 3mo ago
  If your goal is to reduce light pollution, addressing/deflecting the concerns of the surveillance state is probably more likely to get you to that goal than ignoring the concerns entirely or tying yourself to the omnicause
michaelt 3mo ago
I once lived in a city that had replaced street lights that cast light in a circle with modernised ones that cast a sharply delimited rectangle of light on the road, and didn't waste light in other directions. The thing was, the roads of this city were arranged as a footpath, then a grassed area with trees, then the lights, then the roadway. Only after the city had rolled out thousands of these lights did someone notice the footpaths were now much darker. And also the footpaths were quite uneven, due to the trees' roots - a problem the lights had previously been keeping under control. It's now common, in winter, to see groups jogging on the road.
- Rotundo 3mo ago
  Over here, joggers are frequently wearing headlamps to illuminate their way. Often combined with a light on their back. They can see and can be seen, which is safe.
  - michaelt 3mo ago
    There are some fine products on the market compared to a few decades ago, yes. I particularly like the fact rechargeable lights are always at full brightness. Alas when running in a group, the runner in front of you can not just obstruct your line of sight of the pavement, but also the light of your torch. His retroreflective vest becomes the brightest thing in your view. And he's not happy either; backlit by your torch, he casts a shadow forwards and the road ahead is illuminated everywhere except where he's about to step. And of course the tree-lined pavement, while very beautiful and shaded in the summer, isn't very wide. So you can't always run beside the guy. My personal 'solution' is not to run fast enough to keep up with the guy ahead of me, giving me a clear view. But you don't win medals with my attitude.
- wongarsu 3mo ago
  Planners forgetting that pedestrians exist is sadly a common occurrence
- Finnucane 3mo ago
  Get rid of cars and they'd take down all the lights.
Loic 3mo ago
Where I live, we have a small park, 500m away. You need to walk through it if you want to get to the city center from the small neighborhood we live in. To protect the wildlife, the lighting system has presence sensors, so as you walk or bicycle through the park, the way/street lighting turns on, you can walk, and just after you, it turns dark again. Really cool, especially the first time I went through it in the middle of the night.
- fhdkweig 3mo ago
  Those things drive me nuts. There is a walking path that I frequent, and I can't use it at night because they are spaced every 20-30 feet. When I am not under them, they are off and my eyes adjust to the darkness and as I pass under one it flips to full daytime brightness and blinds me. As soon as I walk away from it, everything goes dark again, but my eyes had adjusted to the daytime brightness of the lamps. And I know that in 30 feet, I have to do it again, for the next couple of miles.
  - Loic 3mo ago
    The timing and brightness is well adjusted, it feels natural, like a friendly ghost taking care of you.
    - RetroTechie 3mo ago
      Your Park May Vary (YPMV).
    - fch42 3mo ago
      unfortunately they never are. Brightness-adjusted, that is. Everyone installing lighting fixtures these days believes they must be daylight-level bright. The only ghosts you see are afterimages if you happen to look straight at the streetlamp ... (I find it odd; dark-adapted eyes see a lot, including movement in shadows or low-contrast obstacles - after all, our bodies know how to see well at moonlight levels of illumination. Why are we so keen to kill this ability?)
michael1999 3mo ago
We need much better engineering standards if we are going to fix night lighting. A simplistic lux-on-the-ground measure combined with cost minimization produces a few lights, with bare bulbs, up hight, with brutal intensity. These are all things that produce glare directly on the eyeball. You need much less light on the ground if the eyeball itself has no direct line to the hottest part of the lights. Instead, the night-blindness caused by excessive bare lighting is "fixed" by adding more fill lights for the shadows caused by the first lights. Classic addictive behaviour.
- projektfu 3mo ago
  I believe that is what TFA is about.
  - michael1999 3mo ago
    ctrl-F "standards" - zero results. The fine article was more about the effects of bad lighting, and the motivation to change. It does not discuss the engineering and insurance standards that generate the bad choices. Perhaps you misread my comment. As long as the standards are left as-is, street engineers are going to keep doing as they are.
lysace 3mo ago
The writing style frustrated me immensely. tl;dr: Cheap cool-white LEDs cut energy but worsened light pollution; warmer, dynamically dimmable LED fixtures/infra fix it but lower costs tend to win.
- trollbridge 3mo ago
  Isn't it standard journalism? Instead of just giving us the conclusion we're supposed to think, they interview various people in the field and quote what those people think, and then let us draw our own conclusions.
  - lysace 3mo ago
    No, this is engagement-maxxing style journalism. Complete with the clickbait headline. It also spends almost no time on why the cheaper-but-dumber options win. (Everything is relative. I expect more from IEEE than the NYP or the Daily Mail, as extreme examples.)
- micromacrofoot 3mo ago
  depending on who you ask the cold lighting also magically stops crime
SuperNinKenDo 3mo ago
I hate outdoor LED lights so much, I won't be surprised if a couple decades or centuries from now we discover that these things have been doing permanent damage to people's eyes. It's getting harder and more unpleasant to walk at night, I can't see and my eyes legitimately hurt every couple of minutes.
- BLKNSLVR 3mo ago
  Does this trigger you: Modern car LED headlights There doesn't appear to be any standard being followed (anymore?) on brightness or angle or height (or shape). A selection of them are easy to confuse with high beams. Makes driving at night in the rain some kind of epilepsy inducing overwhelm of lights and reflections and lens flare coming from everywhere, reminiscent of the cyberpunk aesthetic.
  - alt227 3mo ago
    At least in the UK this is being looked into by a government review. Whether that will amount to anything or not remains to be seen, but at least the issue is being taken seriously. https://www.bbc.co.uk/news/articles/cn971jlpvvro https://www.bbc.co.uk/news/articles/cn971jlpvvro
  - trollbridge 3mo ago
    In the U.S., the DOT sets standards, but they only apply to new vehicles sold. Aftermarket lights can be just about anything. (Some are labelled "not for highway use", as if that prevents them from being used on public roadways.) Certain types of people seem to think they should install really, really bright LED lights in their car and then aim them right at other driver's eyes. I believe this comes from a mindset where one is unable to put one's self in another person's aspect, or where one simply doesn't care about others.
    - dec0dedab0de 3mo ago
      I hated these so much until I got a car with a tinted rear windshield, and a self-dimming mirror.
theodorethomas 3mo ago
I wondered if a city-wide synchronised Pulse-Width-Modulation of LED lights could allow astrophotography (or even naked-eye astronomy) to be possible again, with a filter synchronised to the off-cycle.
- fhdkweig 3mo ago
  Los Angeles has the Griffith Observatory. To allow the city to have street lighting while not interfering with the observatory, the lights are sodium vapor lights that emit a specific wavelength that the observatory can filter out. Since LEDs also use specific wavelengths, this could have been done. I was disappointed that the article didn't mention this, especially because they did mention sodium, but only as a pretty color.
  - OkayPhysicist 3mo ago
    I quite like the 2 wavelength light that sodium lamps give out. When I was in school, my university gradually went from all sodium to all LED, and it was definitely a loss. The complete loss of hue, combined with the soft buzz of a dying sodium lamp had a certain otherworldly feel to it. I found it quite relaxing.
- Rotundo 3mo ago
  Using PWM to dim lights should be banned wholesale. Many people, me included, get crazy headaches from the worst lights and mild discomfort from the best ones. It's also completely unnecessary as non-flickering bulbs do exist and are readily available for the same price.
  - weberer 3mo ago
    Those are probably 50-60 hz flickering from the mains frequency rather than PWM. (Or 100-120 hz due to the rectifier). Actual PWM ICs drive LEDs over 10,000 hz, which is truly imperceptible to the human eye.
    - deleted 3mo ago
uv-depression 3mo ago
Greenhouses here in the lower mainland of British Columbia have been devastating to the night sky. It's quite depressing how little society values the night sky, something that's been an important part of every human culture for longer than recorded history. I've taken friends out to thoroughly mediocre skies (Bortle 4-5) and they've been very impressed, because they're used to city lights (Bortle 9) where you can maybe see a few of the brightest stars and planets. If you've never seen truly dark skies, do yourself a favour and go see what they look like during true night. Bring binoculars if you have them, maybe get a planisphere and a (dim!) red flashlight. The lack of respect for the night sky includes starlink and the other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet, by the way. It's been a huge hit to the field of astronomy. Before someone inevitably says "we should just be putting telescopes in orbit", orbital observatories are obviously a huge deal and I support building more of them, but you simply can't put things like the ELT (40m primary mirror, 2800 tonnes) or the Square Kilometre Array in space.
- bpodgursky 3mo ago
  Dude your country is 98% desolate and unsuited to agriculture. If you want night sky go to a cabin literally anywhere in your unending and cold mountains instead of shutting down agriculture in the only marginal spot on the west coast you can grow food.
  - magicalist 3mo ago
    > instead of shutting down agriculture in the only marginal spot on the west coast you can grow food. Not an expert, but I would think greenhouse light pollution is not necessary for agriculture? It seems like obvious waste (money spent generating light that isn't going to photosynthesis), but I assume it's cheaper not to shield the lights than to shield them, so it's a matter of ROI and requiring people take care of their externalities. Is there an economic argument that light shields will make agriculture in that area too expensive?
    - bpodgursky 3mo ago
hectdev 3mo ago
I've started doing this in my home. All lights are smart LEDs. At 8pm, they shift warm, 80%. From 9pm-10pm, they go from 80% to 0%. At 7am, they start going from 0% to 100% cool (I work from home and it helps with focus). Having my environment reflect the patterns of nature has really been a nice change.
- Marsymars 3mo ago
  I do something similar with my exterior lights - at sunset my lights come on at ~1% at 2000K. If they detect motion (in my driveway or back deck) they go up to 100% at 2700K. At sunrise they turn off. Note that bulbs exist that automatically warm as they dim - so in my case the switches are smart, but the bulbs themselves are all dumb.
  - redmaple892 3mo ago
    What type of system are you using outdoors?
    - Marsymars 3mo ago
      * Automation: Home Assistant * Smart switches: Lutron Caseta. (With the dimmer for ELV lighting so I can use the middle button for specific brightness/warmth levels.) * Outdoor bulbs: Philips warm glow bulbs. (2200K-2700K warm dimming, 95 CRI - these ramp from 0% at 2200K to 100% at 2700K) * Outdoor recessed lights: Globe Electric DuoBright LEDs (2000K-5000K warm dimming, 96 CRI - these ramp from 0% at 2000K to full lumens at 3000K at 80% the dimmer, but then will continue to ramp from 3000K to 5000K at full lumens if the dimmer is turned up.) * Motion sensors: Philips Hue Outdoor sensors. Non-smart bulb availability is kinda weird, my specific bulbs may be discontinued or unavailable outside of Canada, but I'd expect local alternatives to be available.
      - redmaple892 3mo ago
        Awesome thank you for sharing. I recently bought a very basic low-voltage system just to have something in the garden but would like to upgrade exterior fixtures at some point and your system seems nice.
binarymax 3mo ago
Our city recently went on a crusade on replacing all of the high pressure sodium bulbs with LEDs, with the justifications of driving safety and energy savings. I agree that these are important, but the LED bulbs they chose are actively hostile to homes and pedestrians. They are blinding. You can't look at them. I have one outside our house in the main viewing angle and we need to close our shades as soon as they are turned on.
- pelotron 3mo ago
  Back in the day the city installed a new streetlight that blinded anyone sitting on the front porch of my grandparents' house, which they liked to do in the evening. So Granddad got out a painter's pole and rolled some white paint onto the side that faced his house. Problem solved and no one ever said anything.
- culi 3mo ago
  :rock: + :slingshot:
  - kakacik 3mo ago
    -> repair, if repeated police or company will maybe put on a little camera, and then suddenly your hobby lands you in jail with enough time in to ponder why childish behavior is ruining one adult's life
deleted 3mo ago
[deleted]
throwatdem12311 3mo ago
All the car headlights for new cars in Canada are LED and it makes driving at night painful and dangerous. So many times I’ve been nearby blinded by them and I can’t see anything ahead. And it actually physically causes me pain.
- yonatan8070 3mo ago
  But is that the fault of the LED? That sounds like the fault of whoever calibrated the LEDs' brightness and directionality. If the beams were the right brightness and pointed downwards, we wouldn't be having this issue.
  - GrinningFool 3mo ago
    Not really. When incandescent headlights are mis-aimed, it is generally not nearly as blinding or painful [for standard car headlights]. Mis-aims happen - it shouldn't be a risk to other drivers when they do.
  - throwaway173738 3mo ago
    There will always be situations where you’ll be under the cut point of a low beam. If there’s a small incline then a flat intersection the drivers opposite the incline get the fill low beam. It’s part of what makes HID lighting dangerous to pedestrians. It obscures the vision of oncoming drivers turning left or right. Also if an automatic headlight system doesn’t react to turn the high beams off it will blind people.
- bahmboo 3mo ago
  I'm optimistic this won't be a problem in 10-20 years (I agree that's a long time). We have the technology in matrix headlights that were banned in the US and basically in Canada up until a few years ago. I expect to see kits on Amazon in a few years for retrofits. Since they need a camera and some brains they will likely start at many hundreds of dollars but that should come down.
redmaple892 3mo ago
I read the entire article and am really glad the author took time to write this down and for OP for posting. I am so tired of poor (mostly outdoor) but also indoor lighting. I have felt crazy feeling that the so-called "better" LED's in parks and on paths have felt like less lighting. Unfortunately I think changing things (in the US) often requires proving harm...science and aesthetics don't seem to matter much at all many place.
chrisweekly 3mo ago
For those in the northeastern US, I highly recommend a visit to Mesawisla in Maine, it's a national dark sky park with cabins and an AMC lodge that provides fantastic food.
- chrisweekly 3mo ago
  argh, typo, too late to edit Medawisla https://www.outdoors.org/destinations/maine/medawisla-lodge/ https://www.outdoors.org/destinations/maine/medawisla-lodge/
miladyincontrol 3mo ago
I think people focus far too much on the temperature of LED street lights and rarely on the CRI. The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI. Dare I argue even I would choose 6500k LED street lights with decent CRI over poor CRI 2700K LED lamps any day.
- tredre3 3mo ago
  > The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI. What makes you say that the CRI causes the lack of soul? I'm not saying that you're wrong, but given that CRI is objectively better than it ever was now, why? The sodium lamps we used previously had a CRI of 25-35. The absolute worst white LEDs we have have a CRI of at least 60.
- krackers 3mo ago
  Sodium vapor lamps didn't exactly have high CRI either
apparent 3mo ago
> The use of solid-state technology gives the lights an extraordinary life-span, often measured in decades rather than years. I have found this not to be the case. They seem to last several years, but not an amazing period of time. Also, the ones that were installed in my home are quite expensive, something like $45 per can (the whole thing must be replaced), and the price to install is $30 per can because the company changed their plug design in the last 5 years. So I end up spending $75 for each light, which is roughly $10 per year per light (per light-year?). That doesn't strike me as a great value, especially because I can't change the lights myself due to the wiring/plug situation. Maybe that piece won't apply in future years, but it's still a lot even if it's just $45 for the darn can.
- aidenn0 3mo ago
  Yes, I was wondering if they really last longer than sodium-vapor lamps, which last about 5 years at a 50% duty cycle.
  - apparent 3mo ago
    I imagine they last longer than some other types, but it hasn't been an order-of-magnitude difference that was advertised. Also the cost/hassle is much more than expected. We've put some smart LED bulbs into some fixtures, and those have been fine. But they've only been in for a few years, so we don't yet know their lifespan.
- adrian_b 3mo ago
  I have seen a lot of complaints about LED lamps with a short life, usually caused by defects in their integrated power supplies, typically arising from bad cooling. On the other hand, I have more than a dozen LED lamps that have been continuously used for more than ten years and none of them has failed yet. They are mounted in classic Edison fixtures for incandescent lamps and they were made by Philips, but at the time when they were bought they were one of their better models, and having a 4000 K color temperature, i.e. very slightly yellowish, but not noticeably yellow, like the lamps with a color temperature less than 3000 K, which try to imitate incandescent lamps.
- 3mo ago
Sparkyte 3mo ago
The lights are not just impacting space but ecosystems switching to LEDs can save ecosystems too.
ButlerianJihad 3mo ago
Since I picked up a Pixel phone, I've been doing some amateur astrophotgraphy, and mostly from the balcony at my apartment. However, I live in a built-up urban area, and my home is absurdly light-polluted. Like, you wouldn't believe it! The parking lot here is ringed with flood lamps that are aimed into our windows. So every hundred feet or so, there is a bright-as-the-Sun lamp in my face, and with a clear view, I can spot about five of them. So from my balcony, my only hope to get some darkness for the camera is to get into shadows. The railings provide a band of shadows that I can use to block the floods from getting on my lens. So if I position the camera juuust right, it kinda feels darker than it is, and I've got to say I've captured some impressive starfields, down to magnitude 9 or dimmer, including bodies such as Uranus and 4 Vesta. I also found that the ballcourts in the rear of my property provide this unique "cave" situation with lots of shadows where I can capture the sky directly overhead, and to the west. This is how I photographed the last lunar eclipse. Now that's my view to the west and 225° (due southwest). If I go on the other side of the property to look east, I've got the same crazy situation with flood lamps, but there's basically no way to hide in shadows. I literally cannot photograph anything rising in the east if it is dimmer than the Moon. So really, my astronomy hobby mostly consists of doing some great editing, curation, identification, and mostly simulation from the comfort of the air-conditioned indoors. I enjoy what sightings I can while outdoors, and that's included some meteors, the ISS, Tiangong, and a few Vandenberg launches. We're still hanging in there!
worik 3mo ago
We have been working hard on this in New Zealand, in the South Island We started in Tekapo (https://www.darkskyproject.co.nz/ https://www.darkskyproject.co.nz/) which being rural with a very low population density, and mountainous and with existing observatories to protect In recent years the effort has moved into the cities (https://www.dunedin.govt.nz/council/policies,-plans-and-strategies/plans/energy-plan/night-sky-city https://www.dunedin.govt.nz/council/policies,-plans-and-stra...) Interestingly people who live on hills, overlooking the suburbs, complain the lovely view of the sparkling streets was going dark! But not only does it preserve the stars it is much cheaper, so not going back Point is: this can be done and the nighttime rewards and financial rewards make it worthwhile
wkjagt 3mo ago
I am Dutch but live in Canada, and when I visit family in The Netherlands, I always notice how much darker it gets during the night, even when my family lives in a larger town than me.
groos 3mo ago
I read through most of the article but didn't see motion sensors mentioned. A lot of suburban streetlights are lighting up empty streets at night. With a combination of motion sensing and LEDs, lighting could follow pedestrians. Cars really don't need street lights in most cases but even then, in higher risk areas, motion sensors could turn on streetlights just as long as needed.
- wffurr 3mo ago
  A motion sensor activated light unpredictably turning off and on on my street would be worse than the steady street lamps we have now. It would be even more distracting and annoying.
thayne 3mo ago
I'm surprised it didn't suggest using red LEDs without phosphorescence, which has several advantages: 1. Red light preserves your dark adaptation 2. It doesn't have as much of an impact on your circadian rythm 3. Not using phosphorescence can increase the lifetime of the light, since you don't have to worry about the coating degrading 4. Red light is less energetic, so could potentially use less power. 5. Since an LED without phosphorescence is a single wavelength, telescopes (and binoculars) can use a narrow band filter to filter out the light pollution, without blocking most of the light from celestial objects.
dwoosley 3mo ago
> “… gives the illusion, without the reality, of safety” This actually isn’t true. Having done physical security work before, a weird fact is that one of the best physical deterrents is lighting; even over CCTV. I don’t say that to take away from this, this is great work and I’d love to see the lighting toned down for multiple reasons. However, this should be framed as a security tradeoff not an outright win. Source: The Impact and Policy Relevance of Street Lighting for Crime Prevention: A Systematic Review Based on a Half-Century of Evaluation Research (https://www.crimrxiv.com/pub/wl9zqxga/release/1 https://www.crimrxiv.com/pub/wl9zqxga/release/1)
- LanceH 3mo ago
  Driving down the road past a police cruiser on the side with it's lights on is far from safe. The escalation of brightness makes them visible beyond anything else...like the road.
mchusma 3mo ago
I am generally for a light government touch, but I think excessive light and sound are forms of pollution and should be generally regulated in a not-overly burdensome way (give people fix it tickets etc). Policing excessive light, and excessive blue light, would be pretty trivial. And I think cameras that automatically ticket loud vehicles would be amazing.
peter_stokes 3mo ago
sodium lamps are much more iconic and pretty. LEDs are gross and soulless

249 points by defrost 3mo ago

I would 100% rather have a truly bright and lively city at night than a visible night sky. More than half the year is in the winter ffs!

dgellow 3mo ago

> Thorp notes that modern CCTV cameras are “pretty great” even at low-light levels, while harsh light makes it hard for both human eyes and digital sensors to see. That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system”

WarmWash 3mo ago
Their prime audience for change are governments...
swiftcoder 3mo ago
> That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system” One of the biggest excuses for ultra-bright streetlights is crime prevention (usually shortly followed by CCTV). I'm not really sure why we continue to indulge that point of view, but if one is indulging it...
- rznicolet 3mo ago
  It's even funnier that, at least around here, one of the biggest crime problems is people stealing copper wiring... from streetlights...
- trollbridge 3mo ago
  The "lights=safety" nonsense shows no sign of coming to an end. Many private residences also install eye-searing levels of lighting outside that they just leave on all night, which is much cheaper to do now thanks to LED technology. There's really no reason for doing it. The idea it deters crime is a long-standing myth (someone analogous to the idea CCTVs deter crime).
- Jblx2 3mo ago
  I know we can be all righteous and intellectual on HN. But the article pretty much glosses over the large number of people who are afraid of the dark. Not afraid of crime in the dark. Actual adults who are apparently having a visceral reaction to the dark. What percentage of people is this? What percentage of those would adapt in a positive manner?
  - swiftcoder 3mo ago
    Those people can carry around a cheap LED lamp if it so pleases them...
mghackerlady 3mo ago
Even then, couldn't you just use IR cameras with IR lights for illumination. I'm sure that comes with it's own set of issues, but strictly speaking is better for maximising surveillance while minimising human impact
pjl0 3mo ago
If your goal is to reduce light pollution, addressing/deflecting the concerns of the surveillance state is probably more likely to get you to that goal than ignoring the concerns entirely or tying yourself to the omnicause

michaelt 3mo ago

I once lived in a city that had replaced street lights that cast light in a circle with modernised ones that cast a sharply delimited rectangle of light on the road, and didn't waste light in other directions. The thing was, the roads of this city were arranged as a footpath, then a grassed area with trees, then the lights, then the roadway. Only after the city had rolled out thousands of these lights did someone notice the footpaths were now much darker. And also the footpaths were quite uneven, due to the trees' roots - a problem the lights had previously been keeping under control. It's now common, in winter, to see groups jogging on the road.

Rotundo 3mo ago
Over here, joggers are frequently wearing headlamps to illuminate their way. Often combined with a light on their back. They can see and can be seen, which is safe.
- michaelt 3mo ago
  There are some fine products on the market compared to a few decades ago, yes. I particularly like the fact rechargeable lights are always at full brightness. Alas when running in a group, the runner in front of you can not just obstruct your line of sight of the pavement, but also the light of your torch. His retroreflective vest becomes the brightest thing in your view. And he's not happy either; backlit by your torch, he casts a shadow forwards and the road ahead is illuminated everywhere except where he's about to step. And of course the tree-lined pavement, while very beautiful and shaded in the summer, isn't very wide. So you can't always run beside the guy. My personal 'solution' is not to run fast enough to keep up with the guy ahead of me, giving me a clear view. But you don't win medals with my attitude.
wongarsu 3mo ago
Planners forgetting that pedestrians exist is sadly a common occurrence
Finnucane 3mo ago
Get rid of cars and they'd take down all the lights.

Loic 3mo ago

Where I live, we have a small park, 500m away. You need to walk through it if you want to get to the city center from the small neighborhood we live in. To protect the wildlife, the lighting system has presence sensors, so as you walk or bicycle through the park, the way/street lighting turns on, you can walk, and just after you, it turns dark again. Really cool, especially the first time I went through it in the middle of the night.

fhdkweig 3mo ago
Those things drive me nuts. There is a walking path that I frequent, and I can't use it at night because they are spaced every 20-30 feet. When I am not under them, they are off and my eyes adjust to the darkness and as I pass under one it flips to full daytime brightness and blinds me. As soon as I walk away from it, everything goes dark again, but my eyes had adjusted to the daytime brightness of the lamps. And I know that in 30 feet, I have to do it again, for the next couple of miles.
- Loic 3mo ago
  The timing and brightness is well adjusted, it feels natural, like a friendly ghost taking care of you.
  - RetroTechie 3mo ago
    Your Park May Vary (YPMV).
  - fch42 3mo ago
    unfortunately they never are. Brightness-adjusted, that is. Everyone installing lighting fixtures these days believes they must be daylight-level bright. The only ghosts you see are afterimages if you happen to look straight at the streetlamp ... (I find it odd; dark-adapted eyes see a lot, including movement in shadows or low-contrast obstacles - after all, our bodies know how to see well at moonlight levels of illumination. Why are we so keen to kill this ability?)

michael1999 3mo ago

We need much better engineering standards if we are going to fix night lighting. A simplistic lux-on-the-ground measure combined with cost minimization produces a few lights, with bare bulbs, up hight, with brutal intensity. These are all things that produce glare directly on the eyeball. You need much less light on the ground if the eyeball itself has no direct line to the hottest part of the lights. Instead, the night-blindness caused by excessive bare lighting is "fixed" by adding more fill lights for the shadows caused by the first lights. Classic addictive behaviour.

projektfu 3mo ago
I believe that is what TFA is about.
- michael1999 3mo ago
  ctrl-F "standards" - zero results. The fine article was more about the effects of bad lighting, and the motivation to change. It does not discuss the engineering and insurance standards that generate the bad choices. Perhaps you misread my comment. As long as the standards are left as-is, street engineers are going to keep doing as they are.

lysace 3mo ago

The writing style frustrated me immensely. tl;dr: Cheap cool-white LEDs cut energy but worsened light pollution; warmer, dynamically dimmable LED fixtures/infra fix it but lower costs tend to win.

trollbridge 3mo ago
Isn't it standard journalism? Instead of just giving us the conclusion we're supposed to think, they interview various people in the field and quote what those people think, and then let us draw our own conclusions.
- lysace 3mo ago
  No, this is engagement-maxxing style journalism. Complete with the clickbait headline. It also spends almost no time on why the cheaper-but-dumber options win. (Everything is relative. I expect more from IEEE than the NYP or the Daily Mail, as extreme examples.)
micromacrofoot 3mo ago
depending on who you ask the cold lighting also magically stops crime

SuperNinKenDo 3mo ago

I hate outdoor LED lights so much, I won't be surprised if a couple decades or centuries from now we discover that these things have been doing permanent damage to people's eyes. It's getting harder and more unpleasant to walk at night, I can't see and my eyes legitimately hurt every couple of minutes.

BLKNSLVR 3mo ago
Does this trigger you: Modern car LED headlights There doesn't appear to be any standard being followed (anymore?) on brightness or angle or height (or shape). A selection of them are easy to confuse with high beams. Makes driving at night in the rain some kind of epilepsy inducing overwhelm of lights and reflections and lens flare coming from everywhere, reminiscent of the cyberpunk aesthetic.
- alt227 3mo ago
  At least in the UK this is being looked into by a government review. Whether that will amount to anything or not remains to be seen, but at least the issue is being taken seriously. https://www.bbc.co.uk/news/articles/cn971jlpvvro https://www.bbc.co.uk/news/articles/cn971jlpvvro
- trollbridge 3mo ago
  In the U.S., the DOT sets standards, but they only apply to new vehicles sold. Aftermarket lights can be just about anything. (Some are labelled "not for highway use", as if that prevents them from being used on public roadways.) Certain types of people seem to think they should install really, really bright LED lights in their car and then aim them right at other driver's eyes. I believe this comes from a mindset where one is unable to put one's self in another person's aspect, or where one simply doesn't care about others.
  - dec0dedab0de 3mo ago
    I hated these so much until I got a car with a tinted rear windshield, and a self-dimming mirror.

theodorethomas 3mo ago

I wondered if a city-wide synchronised Pulse-Width-Modulation of LED lights could allow astrophotography (or even naked-eye astronomy) to be possible again, with a filter synchronised to the off-cycle.

fhdkweig 3mo ago
Los Angeles has the Griffith Observatory. To allow the city to have street lighting while not interfering with the observatory, the lights are sodium vapor lights that emit a specific wavelength that the observatory can filter out. Since LEDs also use specific wavelengths, this could have been done. I was disappointed that the article didn't mention this, especially because they did mention sodium, but only as a pretty color.
- OkayPhysicist 3mo ago
  I quite like the 2 wavelength light that sodium lamps give out. When I was in school, my university gradually went from all sodium to all LED, and it was definitely a loss. The complete loss of hue, combined with the soft buzz of a dying sodium lamp had a certain otherworldly feel to it. I found it quite relaxing.
Rotundo 3mo ago
Using PWM to dim lights should be banned wholesale. Many people, me included, get crazy headaches from the worst lights and mild discomfort from the best ones. It's also completely unnecessary as non-flickering bulbs do exist and are readily available for the same price.
- weberer 3mo ago
  Those are probably 50-60 hz flickering from the mains frequency rather than PWM. (Or 100-120 hz due to the rectifier). Actual PWM ICs drive LEDs over 10,000 hz, which is truly imperceptible to the human eye.
  - deleted 3mo ago

uv-depression 3mo ago

Greenhouses here in the lower mainland of British Columbia have been devastating to the night sky. It's quite depressing how little society values the night sky, something that's been an important part of every human culture for longer than recorded history. I've taken friends out to thoroughly mediocre skies (Bortle 4-5) and they've been very impressed, because they're used to city lights (Bortle 9) where you can maybe see a few of the brightest stars and planets. If you've never seen truly dark skies, do yourself a favour and go see what they look like during true night. Bring binoculars if you have them, maybe get a planisphere and a (dim!) red flashlight. The lack of respect for the night sky includes starlink and the other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet, by the way. It's been a huge hit to the field of astronomy. Before someone inevitably says "we should just be putting telescopes in orbit", orbital observatories are obviously a huge deal and I support building more of them, but you simply can't put things like the ELT (40m primary mirror, 2800 tonnes) or the Square Kilometre Array in space.

bpodgursky 3mo ago
Dude your country is 98% desolate and unsuited to agriculture. If you want night sky go to a cabin literally anywhere in your unending and cold mountains instead of shutting down agriculture in the only marginal spot on the west coast you can grow food.
- magicalist 3mo ago
  > instead of shutting down agriculture in the only marginal spot on the west coast you can grow food. Not an expert, but I would think greenhouse light pollution is not necessary for agriculture? It seems like obvious waste (money spent generating light that isn't going to photosynthesis), but I assume it's cheaper not to shield the lights than to shield them, so it's a matter of ROI and requiring people take care of their externalities. Is there an economic argument that light shields will make agriculture in that area too expensive?
  - bpodgursky 3mo ago

hectdev 3mo ago

I've started doing this in my home. All lights are smart LEDs. At 8pm, they shift warm, 80%. From 9pm-10pm, they go from 80% to 0%. At 7am, they start going from 0% to 100% cool (I work from home and it helps with focus). Having my environment reflect the patterns of nature has really been a nice change.

Marsymars 3mo ago
I do something similar with my exterior lights - at sunset my lights come on at ~1% at 2000K. If they detect motion (in my driveway or back deck) they go up to 100% at 2700K. At sunrise they turn off. Note that bulbs exist that automatically warm as they dim - so in my case the switches are smart, but the bulbs themselves are all dumb.
- redmaple892 3mo ago
  What type of system are you using outdoors?
  - Marsymars 3mo ago
    * Automation: Home Assistant * Smart switches: Lutron Caseta. (With the dimmer for ELV lighting so I can use the middle button for specific brightness/warmth levels.) * Outdoor bulbs: Philips warm glow bulbs. (2200K-2700K warm dimming, 95 CRI - these ramp from 0% at 2200K to 100% at 2700K) * Outdoor recessed lights: Globe Electric DuoBright LEDs (2000K-5000K warm dimming, 96 CRI - these ramp from 0% at 2000K to full lumens at 3000K at 80% the dimmer, but then will continue to ramp from 3000K to 5000K at full lumens if the dimmer is turned up.) * Motion sensors: Philips Hue Outdoor sensors. Non-smart bulb availability is kinda weird, my specific bulbs may be discontinued or unavailable outside of Canada, but I'd expect local alternatives to be available.
    - redmaple892 3mo ago
      Awesome thank you for sharing. I recently bought a very basic low-voltage system just to have something in the garden but would like to upgrade exterior fixtures at some point and your system seems nice.

binarymax 3mo ago

Our city recently went on a crusade on replacing all of the high pressure sodium bulbs with LEDs, with the justifications of driving safety and energy savings. I agree that these are important, but the LED bulbs they chose are actively hostile to homes and pedestrians. They are blinding. You can't look at them. I have one outside our house in the main viewing angle and we need to close our shades as soon as they are turned on.

pelotron 3mo ago
Back in the day the city installed a new streetlight that blinded anyone sitting on the front porch of my grandparents' house, which they liked to do in the evening. So Granddad got out a painter's pole and rolled some white paint onto the side that faced his house. Problem solved and no one ever said anything.
culi 3mo ago
:rock: + :slingshot:
- kakacik 3mo ago
  -> repair, if repeated police or company will maybe put on a little camera, and then suddenly your hobby lands you in jail with enough time in to ponder why childish behavior is ruining one adult's life

deleted 3mo ago

[deleted]

throwatdem12311 3mo ago

All the car headlights for new cars in Canada are LED and it makes driving at night painful and dangerous. So many times I’ve been nearby blinded by them and I can’t see anything ahead. And it actually physically causes me pain.

yonatan8070 3mo ago
But is that the fault of the LED? That sounds like the fault of whoever calibrated the LEDs' brightness and directionality. If the beams were the right brightness and pointed downwards, we wouldn't be having this issue.
- GrinningFool 3mo ago
  Not really. When incandescent headlights are mis-aimed, it is generally not nearly as blinding or painful [for standard car headlights]. Mis-aims happen - it shouldn't be a risk to other drivers when they do.
- throwaway173738 3mo ago
  There will always be situations where you’ll be under the cut point of a low beam. If there’s a small incline then a flat intersection the drivers opposite the incline get the fill low beam. It’s part of what makes HID lighting dangerous to pedestrians. It obscures the vision of oncoming drivers turning left or right. Also if an automatic headlight system doesn’t react to turn the high beams off it will blind people.
bahmboo 3mo ago
I'm optimistic this won't be a problem in 10-20 years (I agree that's a long time). We have the technology in matrix headlights that were banned in the US and basically in Canada up until a few years ago. I expect to see kits on Amazon in a few years for retrofits. Since they need a camera and some brains they will likely start at many hundreds of dollars but that should come down.

redmaple892 3mo ago

I read the entire article and am really glad the author took time to write this down and for OP for posting. I am so tired of poor (mostly outdoor) but also indoor lighting. I have felt crazy feeling that the so-called "better" LED's in parks and on paths have felt like less lighting. Unfortunately I think changing things (in the US) often requires proving harm...science and aesthetics don't seem to matter much at all many place.

chrisweekly 3mo ago

For those in the northeastern US, I highly recommend a visit to Mesawisla in Maine, it's a national dark sky park with cabins and an AMC lodge that provides fantastic food.

chrisweekly 3mo ago
argh, typo, too late to edit Medawisla https://www.outdoors.org/destinations/maine/medawisla-lodge/ https://www.outdoors.org/destinations/maine/medawisla-lodge/

miladyincontrol 3mo ago

I think people focus far too much on the temperature of LED street lights and rarely on the CRI. The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI. Dare I argue even I would choose 6500k LED street lights with decent CRI over poor CRI 2700K LED lamps any day.

tredre3 3mo ago
> The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI. What makes you say that the CRI causes the lack of soul? I'm not saying that you're wrong, but given that CRI is objectively better than it ever was now, why? The sodium lamps we used previously had a CRI of 25-35. The absolute worst white LEDs we have have a CRI of at least 60.
krackers 3mo ago
Sodium vapor lamps didn't exactly have high CRI either

apparent 3mo ago

> The use of solid-state technology gives the lights an extraordinary life-span, often measured in decades rather than years. I have found this not to be the case. They seem to last several years, but not an amazing period of time. Also, the ones that were installed in my home are quite expensive, something like $45 per can (the whole thing must be replaced), and the price to install is $30 per can because the company changed their plug design in the last 5 years. So I end up spending $75 for each light, which is roughly $10 per year per light (per light-year?). That doesn't strike me as a great value, especially because I can't change the lights myself due to the wiring/plug situation. Maybe that piece won't apply in future years, but it's still a lot even if it's just $45 for the darn can.

aidenn0 3mo ago
Yes, I was wondering if they really last longer than sodium-vapor lamps, which last about 5 years at a 50% duty cycle.
- apparent 3mo ago
  I imagine they last longer than some other types, but it hasn't been an order-of-magnitude difference that was advertised. Also the cost/hassle is much more than expected. We've put some smart LED bulbs into some fixtures, and those have been fine. But they've only been in for a few years, so we don't yet know their lifespan.
adrian_b 3mo ago
I have seen a lot of complaints about LED lamps with a short life, usually caused by defects in their integrated power supplies, typically arising from bad cooling. On the other hand, I have more than a dozen LED lamps that have been continuously used for more than ten years and none of them has failed yet. They are mounted in classic Edison fixtures for incandescent lamps and they were made by Philips, but at the time when they were bought they were one of their better models, and having a 4000 K color temperature, i.e. very slightly yellowish, but not noticeably yellow, like the lamps with a color temperature less than 3000 K, which try to imitate incandescent lamps.
3mo ago

Sparkyte 3mo ago

The lights are not just impacting space but ecosystems switching to LEDs can save ecosystems too.

ButlerianJihad 3mo ago

Since I picked up a Pixel phone, I've been doing some amateur astrophotgraphy, and mostly from the balcony at my apartment. However, I live in a built-up urban area, and my home is absurdly light-polluted. Like, you wouldn't believe it! The parking lot here is ringed with flood lamps that are aimed into our windows. So every hundred feet or so, there is a bright-as-the-Sun lamp in my face, and with a clear view, I can spot about five of them. So from my balcony, my only hope to get some darkness for the camera is to get into shadows. The railings provide a band of shadows that I can use to block the floods from getting on my lens. So if I position the camera juuust right, it kinda feels darker than it is, and I've got to say I've captured some impressive starfields, down to magnitude 9 or dimmer, including bodies such as Uranus and 4 Vesta. I also found that the ballcourts in the rear of my property provide this unique "cave" situation with lots of shadows where I can capture the sky directly overhead, and to the west. This is how I photographed the last lunar eclipse. Now that's my view to the west and 225° (due southwest). If I go on the other side of the property to look east, I've got the same crazy situation with flood lamps, but there's basically no way to hide in shadows. I literally cannot photograph anything rising in the east if it is dimmer than the Moon. So really, my astronomy hobby mostly consists of doing some great editing, curation, identification, and mostly simulation from the comfort of the air-conditioned indoors. I enjoy what sightings I can while outdoors, and that's included some meteors, the ISS, Tiangong, and a few Vandenberg launches. We're still hanging in there!

worik 3mo ago

We have been working hard on this in New Zealand, in the South Island We started in Tekapo (https://www.darkskyproject.co.nz/ https://www.darkskyproject.co.nz/) which being rural with a very low population density, and mountainous and with existing observatories to protect In recent years the effort has moved into the cities (https://www.dunedin.govt.nz/council/policies,-plans-and-strategies/plans/energy-plan/night-sky-city https://www.dunedin.govt.nz/council/policies,-plans-and-stra...) Interestingly people who live on hills, overlooking the suburbs, complain the lovely view of the sparkling streets was going dark! But not only does it preserve the stars it is much cheaper, so not going back Point is: this can be done and the nighttime rewards and financial rewards make it worthwhile

wkjagt 3mo ago

I am Dutch but live in Canada, and when I visit family in The Netherlands, I always notice how much darker it gets during the night, even when my family lives in a larger town than me.

groos 3mo ago

I read through most of the article but didn't see motion sensors mentioned. A lot of suburban streetlights are lighting up empty streets at night. With a combination of motion sensing and LEDs, lighting could follow pedestrians. Cars really don't need street lights in most cases but even then, in higher risk areas, motion sensors could turn on streetlights just as long as needed.

wffurr 3mo ago
A motion sensor activated light unpredictably turning off and on on my street would be worse than the steady street lamps we have now. It would be even more distracting and annoying.

thayne 3mo ago

I'm surprised it didn't suggest using red LEDs without phosphorescence, which has several advantages: 1. Red light preserves your dark adaptation 2. It doesn't have as much of an impact on your circadian rythm 3. Not using phosphorescence can increase the lifetime of the light, since you don't have to worry about the coating degrading 4. Red light is less energetic, so could potentially use less power. 5. Since an LED without phosphorescence is a single wavelength, telescopes (and binoculars) can use a narrow band filter to filter out the light pollution, without blocking most of the light from celestial objects.

dwoosley 3mo ago

> “… gives the illusion, without the reality, of safety” This actually isn’t true. Having done physical security work before, a weird fact is that one of the best physical deterrents is lighting; even over CCTV. I don’t say that to take away from this, this is great work and I’d love to see the lighting toned down for multiple reasons. However, this should be framed as a security tradeoff not an outright win. Source: The Impact and Policy Relevance of Street Lighting for Crime Prevention: A Systematic Review Based on a Half-Century of Evaluation Research (https://www.crimrxiv.com/pub/wl9zqxga/release/1 https://www.crimrxiv.com/pub/wl9zqxga/release/1)

LanceH 3mo ago
Driving down the road past a police cruiser on the side with it's lights on is far from safe. The escalation of brightness makes them visible beyond anything else...like the road.

mchusma 3mo ago

I am generally for a light government touch, but I think excessive light and sound are forms of pollution and should be generally regulated in a not-overly burdensome way (give people fix it tickets etc). Policing excessive light, and excessive blue light, would be pretty trivial. And I think cameras that automatically ticket loud vehicles would be amazing.

peter_stokes 3mo ago

sodium lamps are much more iconic and pretty. LEDs are gross and soulless