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The new NYC lampposts also spread wide light cones, which is good for road safety but means they intrude through house windows. Astronomers have also complained

The new NYC lampposts also spread wide light cones, which is good for road safety but means they intrude through house windows. Astronomers have also complained about the lights worsening the "seeing", which is already bad.

mtalantikite 6y ago
Exactly, I wish they at least had some sort of shade on the back towards the sidewalk that stopped it throwing that much light back on the houses. Do we really need that much light on a one way, residential street?
Starwatcher2001 6y ago
"Seeing" is actually about how steady the atmosphere is. The old sodium lights emit in a narrow part of the spectrum which can be mitigated against by using light pollution filters. These allow all light through, except sodium frequencies. Sadly, filters are ineffective against modern LED lighting which emits across a lot of the spectrum.
jacobolus 6y ago
It's actually garbage for road safety because bluer lamps spaced so far apart creates less even lighting, blows out everyone's night vision, causes distracting glare in peripheral vision, and makes it impossible to see into the shadows. The ideal for road safety would be more uniform lighting from a larger number of closer-spaced lamps, placed at lower height, diffused, shielded from the sides, and colored orange (and optionally uniformly dimmer). It would also help road safety to ban the new bluer types of car headlamps, which cause much worse glare than previous yellower ones.
- rootusrootus 6y ago
  > which cause much worse glare than previous yellower ones The color has almost nothing to do with that. Newer headlights are much brighter, and mostly use projectors now. The increase in glare is mostly due to the projectors, because they emit all their light from small point. You'll notice that newer cars with halogen projectors are almost as bad as one with HIDs. It would be interesting to see how a headlight would look if it were able to emit the same amount of light on the road but from a rectangle spanning the entire front of the car. Minimum glare, still effective.
  - jacobolus 6y ago
    > color has almost nothing to do with that The color makes much of the difference. (What really matters is the total intensity in the shorter-wavelength part of the spectrum, so sure, making the lamps much brighter and less diffused is also bad.) Shorter wavelengths cause significantly more glare, because the peripheral part of the human retina is packed with rods and S cones. Intense light including shorter wavelengths also causes the eyes to become bright-adapted, making it harder to see in the dark. The super-bright halogen headlamps emit much more blue light than previous incandescent headlamps, and are included alongside LED headlamps in my complaint here. Bigger, much dimmer, more diffuse lamps would help, but they should also be less blue. (And people should stop mounting headlamps on their SUVs and pickup trucks at other drivers' eye level and aiming them straight ahead.)
quickthrowman 6y ago
I’ve seen exterior fixtures that have shielding options to prevent light from being cast at houses, but it’s an added cost. We sometimes install them on commercial buildings that abut residential areas to prevent light pollution into neighboring homes.

mtalantikite 6y ago

Exactly, I wish they at least had some sort of shade on the back towards the sidewalk that stopped it throwing that much light back on the houses. Do we really need that much light on a one way, residential street?

Starwatcher2001 6y ago

"Seeing" is actually about how steady the atmosphere is. The old sodium lights emit in a narrow part of the spectrum which can be mitigated against by using light pollution filters. These allow all light through, except sodium frequencies. Sadly, filters are ineffective against modern LED lighting which emits across a lot of the spectrum.

jacobolus 6y ago

It's actually garbage for road safety because bluer lamps spaced so far apart creates less even lighting, blows out everyone's night vision, causes distracting glare in peripheral vision, and makes it impossible to see into the shadows. The ideal for road safety would be more uniform lighting from a larger number of closer-spaced lamps, placed at lower height, diffused, shielded from the sides, and colored orange (and optionally uniformly dimmer). It would also help road safety to ban the new bluer types of car headlamps, which cause much worse glare than previous yellower ones.

rootusrootus 6y ago
> which cause much worse glare than previous yellower ones The color has almost nothing to do with that. Newer headlights are much brighter, and mostly use projectors now. The increase in glare is mostly due to the projectors, because they emit all their light from small point. You'll notice that newer cars with halogen projectors are almost as bad as one with HIDs. It would be interesting to see how a headlight would look if it were able to emit the same amount of light on the road but from a rectangle spanning the entire front of the car. Minimum glare, still effective.
- jacobolus 6y ago
  > color has almost nothing to do with that The color makes much of the difference. (What really matters is the total intensity in the shorter-wavelength part of the spectrum, so sure, making the lamps much brighter and less diffused is also bad.) Shorter wavelengths cause significantly more glare, because the peripheral part of the human retina is packed with rods and S cones. Intense light including shorter wavelengths also causes the eyes to become bright-adapted, making it harder to see in the dark. The super-bright halogen headlamps emit much more blue light than previous incandescent headlamps, and are included alongside LED headlamps in my complaint here. Bigger, much dimmer, more diffuse lamps would help, but they should also be less blue. (And people should stop mounting headlamps on their SUVs and pickup trucks at other drivers' eye level and aiming them straight ahead.)

quickthrowman 6y ago

I’ve seen exterior fixtures that have shielding options to prevent light from being cast at houses, but it’s an added cost. We sometimes install them on commercial buildings that abut residential areas to prevent light pollution into neighboring homes.