31–40 of 146 posts
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Don't want to run the lights in the day.
Take them off during the daytime. They're not permanent installments.
But yeah shutters or something smarter (like two-state glass) should work IMO. I think you even get glass that can switch to mirror mode.
I flew through the night to Singapore once. I remember two very striking light sources. Firstly, oil well flares in the Middle East. The oil fields are in the middle of nowhere, so they're these huge orange-red blooms set in utter darkness. Secondly, Delhi. The city is brightly lit with streetlights. But there's a suburb (?) to the south, Faridabad, that's as brightly lit, but with a different, whiter, kind of lights…
Chicago has been slowly replacing its yellow sodium streetlamps with efficient LEDs that project down instead of up. They've been working block-by-block in a systematic way that you can see when you fly into the city at night. It's quite dramatic.
I was very curious what the heck this was and took to Google Maps. Found that it was oil fields as well. I'd personally assumed lighting for workers however and not gas flares.
- https://www.lightpollutionmap.info/#zoom=5&lat=10294175&lon=...
I was looking at light pollution maps just the other day, trying to find places to do astro-photography, and was blown away by how much light pollution there is. Really sucks, because I'd have to drive about 90 minutes out to get into a dark zone.
Only 90 minutes? For me it's at least 3 hours to get to Class 4 on the Bortle scale. Class 2 is probably more than 5 hours. Only alternative is the sea. I'm planning to take a trip to a Class 1 this summer, it'll be hard to find a place that dark that is reasonably reachable though.
Do they really need yellow? Plants do not really need green light (that's why leaves usually reflect green they don't need), so they'd probably be ok with red/blue lamps only. So why yellow?
> with an enormous array of yellow lamps Do they really need yellow? Plants do not really need green light (that's why leaves usually reflect green they don't need), so they'd probably be ok with red/blue lamps only. So why yellow? https://en.wikipedia.org/wiki/Grow_light
Earlier quoted context omitted.
Chicago has been slowly replacing its yellow sodium streetlamps with efficient LEDs that project down instead of up. They've been working block-by-block in a systematic way that you can see when you fly into the city at night. It's quite dramatic.
Did Chicago figure out the issue with LEDs and snow. The old lights melted snow, the LED lights did not
Earlier quoted context omitted.
Chicago has been slowly replacing its yellow sodium streetlamps with efficient LEDs that project down instead of up. They've been working block-by-block in a systematic way that you can see when you fly into the city at night. It's quite dramatic.
Did Chicago figure out the issue with LEDs and snow. The old lights melted snow, the LED lights did not
Streetlights face down and don't have a cavity to fill with snow.