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by BoxOfRain·1y ago·view on hn ↗
>My building replaced all the outdoor lights with them, and now it's just too bright to sit on my stoop at night like used to be so common here in Brooklyn.

What I miss are the old low-pressure sodium street lights that used to be ubiquitous in the UK. Not everyone's cup of tea but they were highly efficient (outperforming LEDs for a surprisingly long time) and had this cool property of being so monochromatic they ate the colours out of everything. This made them useful for astronomers because their light was easily filtered, and reduced their impact on wildlife relative to harsh blueish LEDs. The main reason I like them is aesthetic though, they made night look like night rather than a poor approximation of day.

Thankfully my local area have given up trying to use the really harsh white they put in initially, and have at least starting putting in warmer LEDs.

3 comments
Sodium light story: my family went to Niagara Falls and took a tour of the tunnels behind the falls. The tunnels were lit by sodium lights that were not augmented by phosphors.

It was so monochromatic that we thought we lost our shuttle bus stickers that were stuck to our shirts, and would have to walk around instead of being able to hop-on/hop-off. What a relief it was to emerge in daylight.

> This made them useful for astronomers because their light was easily filtered

The wavelength is so specific that it can have all kinds of cool applications:

https://youtu.be/UQuIVsNzqDk?si=R4VUDCfC6zcHd4XC

I knew what this link was before I clicked it, and it's a must-watch for anyone who's interested in basically any aspect of film making, cinematography, or light science in general. Extremely cool topic.
I already know this is the Mary Poppins Corridor Crew video before clicking. Super cool video.
I did not know those things about the sodium lights, but I did think they were better than the LEDs which are too bright and have other problems. However, I think that they should not put so much light outside in the night time, anyways.