Comment by easygenes
Comment by easygenes 2 days ago
It’s possible to install warm colored LEDs with very little blue light output though. You get all those benefits without giving up the more-suitable-for-night sodium light spectral benefits.
Comment by easygenes 2 days ago
It’s possible to install warm colored LEDs with very little blue light output though. You get all those benefits without giving up the more-suitable-for-night sodium light spectral benefits.
In my city they started turning off all streetlights at midnight outside of major driving lanes and active center areas.
It's weird and somewhat unnerving at first but brilliant. I'd argue road-wise it is possibly even safer because headlights work so much better when it's pitch black by virtue of the human eye having so much dynamic range.
Pedestrians can't miss cars as they're blasting light through the dark; cars can't miss bikes because even passive reflectors are blaring in the surrounding darkness; even pedestrians end up being more visible because of the higher contrast, cast shadows, and movement that conspire to make them plainly pop out like cardboard props or Doom 3 flashlight jumpscares.
And when you go out of the dark zone into a major axis that's bathed in light that feels warm and safe it's like everything is suddenly muted and flattened as if reality went through a low contrast sepia-tinted desaturation filter. You feel like you see better but everything is muddled together in the sameness of uniform lighting.
The experience is highly cognitively dissonant and counterintuitive.
I'm glad that darkness is respected in some places. The need to live in constant light is, to me, unnerving. Light pollution, like noise pollution, creates a myopic dome of sensory oblivion, separating us from experiencing the sounds of nature, the splendor the night sky, the emotions of isolation. I think we'd be better off with a nightly reminder of the natural world and expansive universe beyond our city block.
People are afraid of the darkness.
I really wish that wasn't the case. But removing lights is an uphill battle powered by irrational arguments and doomed to failure even on the cases where it's clearly the best option.
Even dimming the lights is hard.
I was once in the US Navy, and stood many a bridge watch. When it got dark, all outside lights except for the navigation lights (red light on port bow, green on starboard bow, a white light up top and another white light on the stern). And on the bridge, we used only dim red lights, to avoid affecting our night vision. None of the navigation lights was easily visible from the bridge. And you could see reasonably well, even on a cloudy night.
Where I come from they did change the lights to LEDs, but they turn off 2/3rds or 3/4ths of them after midnight; still enough light to navigate, but much less power usage and light pollution. There's a bike lane outside of town whose lights were motion activated, iirc that was installed about 20 years ago.
I walk a lot and support this, even though I am not convinced it makes me more visible when not in front of the headlights. Typically, the danger happens when walking on the sidewalk perpendicular to a road. I can see the car, they cannot see me until I'm a few feet in to the crosswalk when I'm not lit up by a street light.
WTF? What about pedestrians? Are they walking in full darkness?
This seems to be totally oriented to cars. I find American cities incredibly dark by night. Walking around feels too dark and unpleasant.
> WTF? What about pedestrians? Are they walking in full darkness?
During a normal night, you get used to the darkness surprisingly fast, and if there even a slight sliver of moonlight, your eyes will within seconds adjust and let you see things again without trouble.
At least that's my experience growing up in the dark countryside in Sweden and seemingly retaining this as an adult, YMMV.
Also it's terrifying for safety; way too easy to assault someone in complete darkness.
I'm don't see why this is downvoted, I think it's an honest and legitimate question. What are pedestrians supposed to do when there's no car passing them right this moment? Carry their own torch? Rely on ambient light from the moon and reflected from nearby lit streets? Are we assuming there's such a high volume of cars that there's never a gap? I'm genuinely confused.
I'm a regular outdoor runner and also an extreme morning person, so I'm often out running at like 3 AM, and it is absolutely not safer to be in complete darkness. Surfaces are not perfectly uniform and unobstructed and the ambient light from the atmosphere and surrounding city, even dead in the center of a major metro area, is nowhere near enough to see everything you might hit. I've tripped many times and even broken my hand before. It is effectively impossible to ever go full speed.
I run at night on trails (during the summer, when it's too hot to run during the day). I wear a headlamp, and don't trip any more than I do in the day--despite the fact that the trails have rocks and roots. The only issue I have is that because the headlamp is inches from my eyes, shadows are almost invisible.
> The experience is highly cognitively dissonant and counterintuitive.
Hitting the next homeless person and throwing them 10 meter in the space will be quite the experience.
Honestly, this is not shitty experience because of regulation, this is just councils cutting costs everywhere except their salaries. Los Angeles these last couple days has showed what it means to do that. You'll literally be on fire some day.
OK but blinding blue LEDs are most common substitutes, because it's the lazy default, and because people do not care. That's the point of the article.
Blue-white LEDs have become the replacement for High Pressure Sodium [HPS] traffic lights because that's what the LED light companies have to sell. In the early years of the transition to LED streetlights they had to sell blue-white LED streetlights because warmer LEDs were not competitive with HPS on the basis of lumens-per-watt.
Most of the people who understood the advantages of blue-free amber HPS light over white metal halide lights retired, and this little tidbit of information didn't get passed to the next generation of city employees.
> and because people do not care.
People care, but they don't know why they hate the blue-white LED replacement lights. I've complained to the city about their new lights, but have not gotten any responses about why they haven't deployed LED lights with a safe spectrum of color.
This comment about unsafe blue-white headlights got a few upvotes: https://news.ycombinator.com/item?id=42444111
Blue light is safer for cars - it gives slightly faster reaction times, and lower the chance of drivers falling asleep.
The problem is that for pedestrians, the reaction-time is irrelevant, they're butt-ugly, and plenty of people go on night walks because they can't sleep but want to.
Half of this article is basically about cities being overly car-centric.
Or maybe they care about getting to their destination in time and not wasting half a day just going from point A to point B on foot/by (shitty) public transportation, or they'll be fired.
Daily reminder that we live under capitalism where you're not allowed to just "take your time".
I’m not well-read on the old lighting research, but I’ve come across some explanations for why humans actually do much better with amber outdoor lighting than white. One of these points relates to how our pupils expand and contract with the amount of light available.
My impression was that HPS lighting became so widespread not because of the supposed advantages of its light spectrum, but because it was simply the most light-efficient technology available at that time. Here in Germany, only main/multilane streets requiring more lighting were using HPS, residential streets mostly had lamps with white fluorescent lights, so switching those to LEDs wasn't as much of a change. But still, I'm wondering: what about curtains, window blinds etc.? It's not as if people are forced to endure the intrusion of street lighting into their bedrooms?
> But still, I'm wondering: what about curtains, window blinds etc.? It's not as if people are forced to endure the intrusion of street lighting into their bedrooms?
Of course. But that's the problem -- now black-out curtains are required. And maybe you hate those because you really enjoy waking up with the sun streaming in, and now you have to wake up every morning in blackness until you go open the curtains.
The onus shouldn't be on the residents. It's the same as saying, sure it's noisy but why don't you just wear noise-canceling headphones all day long?
Government services exist to serve the people, not make the people work around them.
Low pressure sodium lights were more efficient, but they emit a single wavelength of orange light. These lights were strongly disliked by people who liked to admire their car in the streetlights (I suppose).
> residential streets mostly had lamps with white fluorescent lights,
… they used CFLs? The spiral fluorescents were invented in the 1980’s, I guess. I speculate the residential street lights used mercury vapor bulbs, which had a longer expected lifespan than fluorescents.
> But still, I'm wondering: what about curtains, window blinds etc.?
You need a good blackout curtain to deal with light pollution through your window.
Here in Baltimore the city seems to have purchased a huge batch of defective LEDs that are actually purple. It’s disturbing when you encounter one.
Nitpick: "are actually purple" makes it sound like they came out of the factory purple, but they're actually changing from white to purple over time as the phosphor coating fails.
Just to be clear, these are about 1-3 years old. So yes they probably weren't purple on the day they were installed, but this is a defect and not normal aging. https://www.reddit.com/r/todayilearned/comments/136nz3b/til_...
It happened in NC, too: https://www.dukechronicle.com/article/2024/10/duke-universit...
The city employee who bought them is probably a massive Ravens fan...
Not true, they're just defective and degraded quickly, resulting in the odd color.
Agree, but it's more expensive and less energy efficient[1]. Personally, that seems worth it to me [EDIT: "it" being using slightly less efficient lights that are more comfortable for people], but thats a difference in values not in how much I "care" about the problem...
[1] https://www.scientificamerican.com/article/streetlights-are-....
> that seems worth it to me
How much more energy efficient is it? If it's a tiny efficiency gain vs the negative effects of blue heavy white light then I would suggest it's a bad tradeoff. Some studies have suggested that blue light doesn't affect sleep [1] but the psychological effects of cold vs warm light has been used by lighting designers for decades. Cold light is less comfortable and discourages hanging around, the positive spin is "energizing", it's often used in supermarkets and budget stores that value faster browsing, and impulsive decisions under a greater feeling of urgency. Warm light has a relaxing effect and is used, for example, in luxury stores and restaurants where people are intended to take their time. [2] For outdoor areas where people are intended to enjoy relaxing after dark activities warmer light would be far superior an experience than colder light.
1. https://www.medicalnewstoday.com/articles/blue-light-may-not... 2. https://www.tcpi.com/how-lights-impacts-psychology-mood-in-r...
sure - for your house. For lights all over the city that will be lasting years?
In my town, when they replaced the old mercury arc and high pressure sodium lights, they picked a pleasing neutral white for the side streets that's far better than the bluish-white mercury arcs they replaced, while using 40 watts each instead of 175. Win-win in my book.
The main streets have a different LED with a slight yellow cast, but not the ugly orange of high pressure sodium. Yes, we can have nice LED street lighting.
Use a CD disk - really - it disperses light similarly to a dispersive prism. You can then see and estimate the amount of red, blue and green in a light. It works very well if you just want to check blue light sources at night. And you can even make a DIY spectrometer with it! https://youtu.be/p3MzQ1OF3lk
The funny thing is, in my neck of Seattle (the city this post is complaining about), I've seen some of the harsh white LEDs that went in switched over to a warmer color. I remember being quite shocked when I pulled into a city-owned parking lot one night and realized that all of the lights around were all now a warmer color instead of the harsh white. The lights in my neighborhood also seem to have been switched over at some point. I suppose they're the tunable LEDs, but clearly someone here does care.