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LEDs’ potential to save our night skies

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Re: LEDs’ potential to save our night skies

#81

Post by [deleted] »

weberer wrote: post #40
Rotundo wrote: post #23

Earlier quoted context omitted.

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.

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]

Re: LEDs’ potential to save our night skies

#82

Post by redmaple892 »

Marsymars wrote: post #77
redmaple892 wrote: post #73

Earlier quoted context omitted.

What type of system are you using outdoors?

* 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…

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.

Re: LEDs’ potential to save our night skies

#83

Post by ninalanyon »

trollbridge wrote: post #19
Loic wrote: post #5

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 mid…

Wouldn't it be more reasonable to just expect people who want to walk places in the dead of night to wear a headlamp? They're cheap, easy to recharge, and can be adjusted for various brightness levels.

No. Unless you expect everyone to always have those things you will need the street lights anyway so why not make them smart and efficient. This especially applies in northern latitudes where it is dark in the evening even before people leave work.

Re: LEDs’ potential to save our night skies

#84

Post by drdexebtjl »

bpodgursky wrote: post #55
eliaspro wrote: post #53

Earlier quoted context omitted.

This is not only about being able to see a nice night sky (although I admit I love seeing one), it's a very much more fundamental issue. Light pollution has dramatic negative consequences for wildlife and thereby our ecosystem we so heavily depend upon.

Yes it has negative consequences for wildlife, which is why it is FAR BETTER FOR THE ENVIRONMENT to put all the agriculture in one place at high efficiency rather than spread farmland out over otherwise virgin wilderness. Would you rather have 2x the wilderness 80% degraded or 1x the wilderness 90% degraded? Unless your plan is to decide who starves to death, it's far better to have greenhouses where we already have…

Stop with the false dichotomies. I would rather have no wilderness 90% degraded at all. There are better alternatives than spreading out the farmland. Like better greenhouses that don’t blast grow lights all over the night sky. We have the technology, it’s just cheaper to destroy the environment.

Re: LEDs’ potential to save our night skies

#85

Post by chickensong »

Hilliard_Ohiooo wrote: post #69
uv-depression wrote: post #25

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 ma…

It's not that big a deal for MOST people. I was on navy ships transiting the Pacific it's as dark as it can get on deck and sure, it's magical and spectacular (especially the NUMBER OF SHOOTING STARS!) but even in the middle of the ocean 99% of my fellow sailors could not have given less of a shit. I'd sit out there for hours and they all though I was a weirdo for it. So, while amazing, most people don't understand o…

There are a lot of Muggles in the world.

Re: LEDs’ potential to save our night skies

#86

Post by redlewel »

Loic wrote: post #5

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 mid…

Would prefer very dim or red lighting. Also preserves your night vision

Re: LEDs’ potential to save our night skies

#87

Post by PaulHoule »

adrianN wrote: post #39
uv-depression wrote: post #25

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 ma…

Putting astronomy on the dark side of the moon would probably work better than putting it into space because you can use some local material for construction.

In space though you can do extremely lightweight construction because structures don't need to support their weight against gravity unless they are huge enough that tidal forces matter.

Like O'Neill's research group killed off the plan with the big cylinders because you would construct solar power satellites out of plastic films with vapor deposited metal and semiconductors and these would be light enough to send up from Earth and assemble in space.

Re: LEDs’ potential to save our night skies

#88

Post by PaulHoule »

adrianN wrote: post #41
amiga386 wrote: post #36

Earlier quoted context omitted.

The problem is not just with people who want to walk places, but people who want to mug/murder/rape those that do. As an example, in the UK, councils are expected to light commonly-traveled paths, both so path users can see where they're going, and to reduce crime. Unlit paths in city parks are still traversed, and are often a haven for crime. "Dead of night" isn't the right image. 5PM in winter with clouds (as is ty…

TFA claims that lights don’t reduce crime, but I‘d like to see the exact meaning of that statistic (eg dark places are less frequented hence less crime?).

Lights help criminals see what they are doing.

Re: LEDs’ potential to save our night skies

#89

Post by wussboy »

kortilla wrote: post #59
uv-depression wrote: post #25

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 ma…

> other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet Ah yes, that municipal internet in the Pacific Ocean. The municipal internet in the 1 person per square mile rural area. The municipal internet to mountain villages. The municipal internet running to airplanes. The municipal internet to the Antarctic research stations. Tell me you don’t know the point of…

Maybe it's okay for there to be places on the earth where high sped internet is not available?

Re: LEDs’ potential to save our night skies

#90

Post by drdexebtjl »

kortilla wrote: post #59
uv-depression wrote: post #25

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 ma…

> other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet Ah yes, that municipal internet in the Pacific Ocean. The municipal internet in the 1 person per square mile rural area. The municipal internet to mountain villages. The municipal internet running to airplanes. The municipal internet to the Antarctic research stations. Tell me you don’t know the point of…

> The municipal internet in the 1 person per square mile rural area.

Yet that person can receive mail, is within a few miles of a major highway, and is likely connected to or close to the electric grid.

Infrastructure is expensive. LEO Satellite internet is only cheaper because the environmental cost is not being accounted for.

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