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> but the street looks nicer (it's in color). Streetlights aren't for doing your makeup, they're for seeing hazards in the roadway that are beyond the range of

> but the street looks nicer (it's in color). Streetlights aren't for doing your makeup, they're for seeing hazards in the roadway that are beyond the range of a vehicle's headlights. Orange is the ideal color for outdoor lighting, because of the way the light-sensitive proteins in our eyes are 'tuned' ('cones' and 'rods', 'photopic' to 'mesopic' and 'scotopic', etc). My notes from a few years ago: https://teslabox.com/2020/01/color-vision-night-vision-notes/ https://teslabox.com/2020/01/color-vision-night-vision-notes... - tl/dr: peripheral vision is tuned to blue, 2 of the 3 color-sensitive proteins are highly sensitive to orange light. Curious: why did you link to that particular thread? 66 comments, including one by yours truly. imho, this is the best of that thread: https://news.ycombinator.com/item?id=19855545 https://news.ycombinator.com/item?id=19855545

wkat4242 3y ago
True but there's still the issue that you won't see objects of certain colors when illuminated by sodium lamps. That could be a traffic hazard. With full spectrum light that's only the case for full black objects. Colour rendering doesn't have to be perfect for this use but having full spectrum coverage does have its advantages.
- ars 3y ago
  It's a very rare object that reflects nothing in the yellow-orange of sodium lamps. You'll just see a kind of black and white (except in yellow) version of the object. Also, they have high pressure sodium bulbs that widen the color, and then I don't think there are any objects you won't see.
- llampx 3y ago
  Metal halide (MH) bulbs have been used for a long time now in street lighting, low-pressure sodium vapor (LPS) was just one of the first applications of the technology. Metal halide has a much whiter/bluer light and covers more of the spectrum than LPS. I do believe though, that LEDs for such industrial applications don't or shouldn't suffer the same issues as the little LED bulbs we buy for the home, due to better QC and construction.
ars 3y ago
I agree about the color - I just wanted to be fair about the advantages of LEDs. In my city the main streets (commercial mostly) are white LEDs and the side streets (residential) are sodium, and I like it that way. I linked the thread because it's old, and has exactly this topic.

wkat4242 3y ago

True but there's still the issue that you won't see objects of certain colors when illuminated by sodium lamps. That could be a traffic hazard. With full spectrum light that's only the case for full black objects. Colour rendering doesn't have to be perfect for this use but having full spectrum coverage does have its advantages.

ars 3y ago
It's a very rare object that reflects nothing in the yellow-orange of sodium lamps. You'll just see a kind of black and white (except in yellow) version of the object. Also, they have high pressure sodium bulbs that widen the color, and then I don't think there are any objects you won't see.
llampx 3y ago
Metal halide (MH) bulbs have been used for a long time now in street lighting, low-pressure sodium vapor (LPS) was just one of the first applications of the technology. Metal halide has a much whiter/bluer light and covers more of the spectrum than LPS. I do believe though, that LEDs for such industrial applications don't or shouldn't suffer the same issues as the little LED bulbs we buy for the home, due to better QC and construction.

ars 3y ago

I agree about the color - I just wanted to be fair about the advantages of LEDs. In my city the main streets (commercial mostly) are white LEDs and the side streets (residential) are sodium, and I like it that way. I linked the thread because it's old, and has exactly this topic.