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Simple streetlight hack could protect astronomy from urban light pollution

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Re: Simple streetlight hack could protect astronomy from urban light pollution

#101

Post by cassianoleal »

Terr_ wrote: post #72
cassianoleal wrote: post #54

Earlier quoted context omitted.

I'm still unsure what you're advocating for. Dim, but cool coloured lights? That's certainly better than bright cool ones but I still find them very annoying and overstimulating at night. The only thing I can't do with dim, warm lighting is read small text from something other than a backlit screen. For everything else, it's perfectly fine. And if I do see myself having to do that, I'll just add a spot of light to wh…

I think their point is that all the wavelengths that make the lights most-useful from a safety perspective are also those which interfere with seeing the stars and whatnot.

Ok, but that's where I'm confused. You don't need to see everything in full colour and detail to be safe. You need to be able to make out shapes, movements and shadows.

A few years ago I lived in a neighbourhood where all the street lights had a dark yellow tint, very warm coloured. They weren't all that bright either. I could see a person a block away with ease.

Again, that was far from ideal to read a book, but why would I do that out on the streets at night?

Re: Simple streetlight hack could protect astronomy from urban light pollution

#102

Post by mortehu »

sleepybrett wrote: post #93
cjensen wrote: post #86

Earlier quoted context omitted.

Why do you think 150Hz is unacceptable? People used to watch 50Hz TV, and weren't bothered too much. And San Jose used to use 60Hz flickering streetlights (sodium? not sure) to reduce light pollution for Lick Observatory.

because tvs used phosphors it isnt really on/off 50hz just a slight light dip.

If you look at high speed footage of a CRT monitor, you'll see that only a few scan lines are lit at a time.

https://www.youtube.com/watch?v=3BJU2drrtCM&t=150s

Re: Simple streetlight hack could protect astronomy from urban light pollution

#103

Post by fy20 »

fragmede wrote: post #29
persnickety wrote: post #28

> But there is a downside to LEDs: They're much brighter than old-fashioned energy-guzzling light bulbs. Are light bulbs actually being used in street lighting? I can't recall ever seeing that. Typically there's some gas-discharge lighting for that, and as far as I know, good old sodium-vapor lamps are pretty energy-efficient, on top of being not-terrible for astronomy. This makes me wonder: what are LEDs replacing?…

Cheaper to operate, which over an entire city's worth of street lamps is very material. Sodium-vapor lights eventually need to be replaced (as do LEDs), so why not replace them with a modern technology that's cheaper to operate?

Actually they aren't in terms of energy. High pressure sodium lamps output around 100 lumens per watt, which is the same as LEDs.

I'd imagine some LED luminaries are consuming more energy than the sodium lamp they replaced, as they are usually brighter and some will have terribly inefficient power supplies.

Re: Simple streetlight hack could protect astronomy from urban light pollution

#106

Post by mcbishop »

petee wrote: post #2

In my area I've noticed the problem isn't so much that they are brighter, but that our new bulbs just emit light near 180 degrees (sideways) with no control over direction. It causes light to flood into homes, and more than half isn't even illuminating the road. They also have no diffusion, so its harsh on the eyes. A bad design all around

I wonder if some jurisdictions assume people prefer having the light go far and wide, for security / safety.

Re: Simple streetlight hack could protect astronomy from urban light pollution

#108

Post by AngryData »

probably_wrong wrote: post #59
todfox wrote: post #56

This doesn't help people like me who just want to stargaze. How about, empty city streets don't need to be lit up at 2 am. And what lighting there is, is too bright, too intrusive, and overused.

As a man I'm all for it. But I think the women I know would object to walking at night on pitch-black streets.

I see the problem as completely opposite. Streetlights ruin your night vision so you can't see in all the dark areas people could be hiding.

Re: Simple streetlight hack could protect astronomy from urban light pollution

#109

Post by pneumic »

Seeking advice on how to lobby my city to disable a streetlight. We are on a rural road next to conservation land, and it blasts our house with light through the night, distracting our son with autism. Considering getting an instrument to measure the light's intensity and gathering data. Any tips on how to lobby a city government with such an unusual request would be greatly appreciated.

Re: Simple streetlight hack could protect astronomy from urban light pollution

#110

Post by esaym »

pneumic wrote: post #109

Seeking advice on how to lobby my city to disable a streetlight. We are on a rural road next to conservation land, and it blasts our house with light through the night, distracting our son with autism. Considering getting an instrument to measure the light's intensity and gathering data. Any tips on how to lobby a city government with such an unusual request would be greatly appreciated.

Just shoot it. It'll never get noticed.
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