Author Topic: What's happened to light bulbs?  (Read 7125 times)

hellymedic

  • Just do it!
Re: What's happened to light bulbs?
« Reply #50 on: 24 March, 2017, 11:58:06 am »
Astronomers are nostalgic for sodium orange, which they can largely filter out.
Broad spectrum LEDs pollutes the night sky with glare which can't be filtered and contains enough blue to scupper night vision.

Cudzoziemiec

  • Ride adventurously and stop for a brew.
Re: What's happened to light bulbs?
« Reply #51 on: 24 March, 2017, 12:03:19 pm »
Yes, I'm aware that astronomers prefer sodium orange – though surely most of all they prefer darkness. Are LEDs worse in this respect than other 'white' streetlights (mercury, fluorescent, tungsten, etc)?
Riding a concrete path through the nebulous and chaotic future.

hellymedic

  • Just do it!
Re: What's happened to light bulbs?
« Reply #52 on: 24 March, 2017, 12:13:40 pm »
TBH it's a long time since I've seen a mercury street light!
Astronomers tend either to observe at, or close to home, where they are at the mercy of whatever their municipality throws at them, or select some distant dark sky site, where they must hire or bring hefty, bulky kit.
David observes from home, where scopes are fixed to the ground and immediate shelter is available should the weather turn. Sky glow is getting worse all the time.

caerau

  • SR x 3 - PBP fail but 1090 km - hey - not too bad
Re: What's happened to light bulbs?
« Reply #53 on: 24 March, 2017, 12:47:34 pm »
Yes, I'm aware that astronomers prefer sodium orange – though surely most of all they prefer darkness. Are LEDs worse in this respect than other 'white' streetlights (mercury, fluorescent, tungsten, etc)?


There were stories all over the BBC a couple of weeks back about how many residents in US cities like Washington D.C. and NY are no longer able to sleep due to the blue LED streetlights that they now have.  I know there will always be whingers about any change like that but in this case I can see a real problem in there.
It's a reverse Elvis thing.

tonycollinet

  • No Longer a western province of Númenor
Re: What's happened to light bulbs?
« Reply #54 on: 24 March, 2017, 01:13:05 pm »
I recently bought two of these
https://www.amazon.co.uk/gp/product/B01II9VPNA/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

For the bedroom. For me they give a lovely warm glow (Very warm) if a bit dim. I suspect that they are of the cheaper import variety, but I've not noticed any flicker. I'll experiment with various video cameras.

Will also have to wait to see how long they last.

Kim

  • Timelord
    • Fediverse
Re: What's happened to light bulbs?
« Reply #55 on: 24 March, 2017, 01:22:23 pm »
They are replacing street lamps with LED. One day we will get all nostalgic for Sodium Orange!

They installed LED streetlights around here a while ago.  They match the colour temperature of my bike lights, which is novel.

The light appears cold, but it's not like sodium is pleasant either.

They seem to do an admirable job of illuminating things on the road.

Main objection is that they've used half as many poles as previously, with the fixtures having a wider spread.  This means more dark shadowy pavements.  I can't imagine it helps with light pollution either, although the optics do seem to have a very sharp cut-off.

Kim

  • Timelord
    • Fediverse
Re: What's happened to light bulbs?
« Reply #56 on: 24 March, 2017, 01:24:54 pm »
Elsewhere, someone is talking about migraines brought on by the flickering effect of traction poles casting shadow/light patterns when looking out of a train window. Similar problem?

Seems likely.  Citation needed, but I believe photosensitive epilepsy was first discovered through the combination of horses and avenues.

Kim

  • Timelord
    • Fediverse
Re: What's happened to light bulbs?
« Reply #57 on: 24 March, 2017, 01:32:51 pm »
There were stories all over the BBC a couple of weeks back about how many residents in US cities like Washington D.C. and NY are no longer able to sleep due to the blue LED streetlights that they now have.  I know there will always be whingers about any change like that but in this case I can see a real problem in there.

Lighting fixtures should be installed so as not to shine light directly into windows.  Barndoors (or whatever they're called in a street lighting context) and thoughtful placement of lamp posts aren't rocket science.

As for general urban glow keeping people awake, curtains and blinds aren't rocket science either.

In the days before smartphones, when torch batteries were expensive, children needed spill from streetlights for their illicit reading after bedtime activities...


It (along with the urban astronomy issue) does raise the interesting question of whether a broad spectrum is actually a good idea for street lighting.  LEDs can be made in any colour you like, and perhaps a monochromatic green (hitting the peak response of the human eye) or a night-vision-friendly red would have merits, if not public support.

barakta

  • Bastard lovechild of Yomiko Readman and Johnny 5
Re: What's happened to light bulbs?
« Reply #58 on: 25 March, 2017, 11:39:06 am »
They are replacing street lamps with LED. One day we will get all nostalgic for Sodium Orange!

They installed LED streetlights around here a while ago.  They match the colour temperature of my bike lights, which is novel.

The light appears cold, but it's not like sodium is pleasant either.

They seem to do an admirable job of illuminating things on the road.

Main objection is that they've used half as many poles as previously, with the fixtures having a wider spread.  This means more dark shadowy pavements.  I can't imagine it helps with light pollution either, although the optics do seem to have a very sharp cut-off.

I don't think these LEDs flicker (their predecessors bloody do).

I find the dark shadowyness very difficult cos it makes the lighting uneven so I can't get a sense of a consistent light level. I'd rather they didn't bother, or indeed the red/green suggestion you made else thread.  Oh and they're only on one set of pavements so clearly for cars not pedestrians.

Re: What's happened to light bulbs?
« Reply #59 on: 03 April, 2017, 07:24:41 am »
Streetlight Fight in Rome: Golden Glow vs. Harsh LED
Quote
a plan to replace the city’s yellow sodium streetlights with cheaper, more environmentally friendly, white LED lamps is, for some, not simple modernization, but sheer heresy.

However, I am pleased to say they now turn off the sodium light in my French hameau late at night.  It has just the one.  Then there is only star and moonlight in the sky.
Move Faster and Bake Things