This is a good write up about the LED street lights that fail by turning purple. I took a panoramic picture of purple streetlights in Phoenix recently: https:/

This is a good write up about the LED street lights that fail by turning purple. I took a panoramic picture of purple streetlights in Phoenix recently: https://twitter.com/jamesknochel/status/1762862867861451027 https://twitter.com/jamesknochel/status/1762862867861451027 I spoke with someone who worked on Phoenix’s streets department. Around 2015 they pulled all their high pressure sodium lights and replaced with 4000k led fixtures. After a while they did it again, replacing the 4000k leds with 2700k. They’re slightly less obnoxious than the 4000k fixtures, but inferior to ~2000k (almost blue-free) high pressure sodium bulbs. The main advantage of LED fixtures over high pressure sodium bulbs is the LEDs were supposed to last 10 years, whereas the HPS bulbs have to be replaced every 5 years. HPS bulbs are much better for safety, as our eyes work best with orange light under low-light conditions. Edit: Phoenix’s page about their led conversion: https://www.phoenix.gov/streets/led https://www.phoenix.gov/streets/led