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roughlyyesterday at 7:05 PM5 repliesview on HN

I'm reminded of an article a while back talking about how the change from sodium streetlights to LED streetlights had a whole lot of unforeseen effects on animals, people's sleep patterns, driver awareness and visibility, etc. due to color changes. There was a comment on the article from an old civil engineer saying "no, these were not unforeseen, we actually did the research back in the day to figure out what color the street lights should be, that's why they were the color they were."


Replies

SyzygyRhythmyesterday at 7:33 PM

> that's why they were the color they were

That doesn't seem right to me. Sodium (and mercury) vapor lamps are the color they are due to physics, and were chosen because they're very efficient (and long lasting). Low-pressure sodium is the best and worst of these; essentially monochromatic but fantastic efficiency. Their only advantage, color-wise, is that the light can be filtered out easily (they used to be widely used in San Jose because Lick Observatory could filter out the 589 nm light).

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linkjuice4allyesterday at 7:25 PM

I think we've learned a couple of times that lighting placement, temperature, and shadow-casting are not ideal [0]. Also some of the newer lighting does actually fade to a different color [1] so it's not just the base temperature of the new lights.

[0] https://en.wikipedia.org/wiki/Moonlight_tower

[1] https://sigostreetlight.com/blogs/common-quality-problems-in...

throwaway27448yesterday at 9:09 PM

The posted article seems like credulous commentary, though.

anthkyesterday at 10:33 PM

I miss the aesthetics of the support for the street light themselves too. In Spain they used to be curved with a 'crown' shaped top, looking 'classical' and less hard for the brain as straight lines make the brain really tired. We are used to fractal and curved designs from nature, not to fake perspective points in every city full of straight lines.

These could just reuse the current LED lamps by just redesigning the socket. Altough the materials should be changed as the old ones (I think they were ceramic and/or concrete?) could cause serious harms if they felt over random people walking around. And, yes, they can even break concrete pavement like nothing.

I remember hearing a falling lamp+case near my home and upon falling to the sidewalk it sounded like a bomb, I am no kidding, even the floor vibrated and the windows nearly crashed. These things were really sturdy, either concrete or cement. I would love the same design but in magnesium, which can be lighter and maybe as durable, altough I know ceramic/concrete can withstand anything.

cucumber3732842yesterday at 7:30 PM

I'm sure tons of people along the way "noticed" but if you're selling LEDs or you're paid by the LED people to create marketing to convince people that LEDs are gonna save the planet, you're not gonna bring that up.

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