My experience has been exactly the opposite. My neighborhood went from yellow, sodium lighting to stark white LEDs a few years ago. The result, to my eyes, is that the contrast between what is lit by the street lights and surrounding dark areas is much higher. Perhaps what is needed is better diffusion onto the ground.

Or 2000K wide spectrum LED lamps vs doing stupid 6000K-5000K LED lamps at night and messing with human sleep cycles even more :/ Or causing nausea with the narrow spectrum yellow sodium lamps.

the problem with 2000k lights is that human night vision is much more sensitive to bluer light. you can use about half as much light while appearing as bright by moving to 3500k

>It seems to make everything really dark in my neighborhood.

When it comes to using lights that actually allow the night sky to be seen, that's kind of the point.

(out of context) It depends, I personally definitely like the yellow variant when it's foggy or snowing. On some days I'm very sensitive to white light (kind of blinds me), I'm currently guessing that it depends on how much I slept throughout the week?.

Here ( https://upload.wikimedia.org/wikipedia/commons/c/cf/Tokyo_To... ) is a pic of the Tokyo Tower in Japan => I read that apparently they often use yellow light during winter on snowy/foggy days to provide a sense of "warmth", during summer they tend to use more often white light => interesting.

That's true. Inside my home I prefer yellow light, but on the streets white light does work a lot better.

I know it's psychological, but white light also gives me a better sense of security walking at night on the street.

There are some weird claims correlated with bluer light... that in public spaces they reduce crime or suicide rates. There's not a lot of actual data, but I've seen a lot of articles about it pop up... maybe it's just everyone's predilection towards easy fixes for complicated problems (like the too-rosy broken windows theory claims)

https://urbanlabs.uchicago.edu/projects/crime-lights-study

Blue light is generally bad circadian rhythms (animals and humans):

* https://www.darksky.org/why-is-blue-light-at-night-bad/

Another study on crime and streetlights:

> A 2015 study published in the Journal of Epidemiology and Community Health found that streetlights don’t prevent accidents or crime, but do cost a lot of money. The researchers looked at data on road traffic collisions and crime in 62 local authorities in England and Wales and found that lighting had no effect, whether authorities had turned them off completely, dimmed them, turned them off at certain hours, or substituted low-power LED lamps.

* https://www.darksky.org/light-pollution/lighting-crime-and-s...

So that 2015 study looks at light versus less light, but the claim I've seen circulated quite often is that the color of the light makes a difference. It seems dubious and has little backing information... and I guess my question is why it's become such a popular theory.

Blue light is preferred because it makes it difficult (impossible?) to Shoot Up. ‘Reduce crime & suicide’ is a euphemism.