The city night is so blue wave spectrum nowadays, so stark and relentless. I miss the sodium lights of my youth. When every street lampost was a dull orange/yellow. The night was actually night, there was a cloak to it; not a stay-glo stadium new form of electric day. I know it's nostalgia, and yes - I am just lamenting a passing of an age. But I thought I'd say it out loud here; who remembers the nights of Low-Pressure-Sodium? When everything around you was through an amber filter? All colours around you reduced to browns, blacks, & oranges. I guess it's a different reality at night for people now. The whites and blues, same as phone screens, lighting our streets. RIP orange murk Gothic.
Red and Black cars in sodium light night time. File:Red and black cars under low pressure sodium lamps.jpg - Wikimedia Commons
Article on heath under modern LED lighting systems... https://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html
When stupid governments were told that LED produced ten times the number of lumens per watt than tungsten, along with lasting for 15,000 hours, they neither bothered to check the lumen efficiency of SON, SOX, Mercury or Halide. Neither did the realise that LED output falls off so fast, the reflected light is so poor, or that while the LED lasts, the control gear does not. Some of the new lamps have produced no saving, while in the case of SOX (low pressure sodium) have actually increased the wattage. Now we are driving around dazzled by the bulbs, with not enough light on the road to se where we are going Along came the experts again and reduced the peak of the LED's SED curve from 3,200k, to 2,800k. Now we have less light and everything is the colour of mud. To make matters even worse, we have sent all the money down a one way street to China
I dunno, the 3000k LED streetlight they have in front of my house is significantly better than the earlier high-pressure sodium, HPS, bulb at half the wattage. What I have noticed is they have far improved the directivity and far less of the light is wasted - it all points down, in a beam pretty much the width of the road - not scattered all over sky - you can really see how that works in the fog. They've got the LED life down, it may fall off 10% over the LED life, but 90% of the LED lamp failures are in the power supply - which, of course, is designed on the razor's edge of adequacy. I think we have all been disillusioned over LED life from the cheap bulbs we use in our home fixtures - they usually crap out in a thousand hours or so from heat and poor thermal design, as with the earlier cork screw fluorescent bulbs. I've torn many of them down for analysis after they've puked and it usually the same thing... The color rendition of the HPS is really crappy, but produced far more usable Lumens per watt than the metal halide or mercury vapor bulbs, which is why they were rarely used inside. HPS was pretty much the only better solution at the time - the low pressure sodium LPS tubes were much more efficient, but they were very orange. For a while, they came up with a phosphor coated HPS that was pretty white.... Yes, we can't do much about China...that is why Cree got out of the LED biz. The only way they could make it with producing LEDs was constant innovation and building the best lumen per watt device and be able to sell it long enough until China copied it and flooded the market. Who remembers incandescent streetlights? They'd have a 500 watt bulb in a ceramic reflector - they would string a group of bulbs in series (like xmas lights) so they would only have to string one wire in a loop, run off of a higher voltage line. If one bulb burned out, there was a burn out clip on top of the fixture - two contacts separated by an insulating disk that would burn off when the higher voltage appeared across the open bulb...pop! I think we have just grown accustomed to the dim yellow from tungsten bulbs most of our lives....but tungsten bulbs are precisely just heaters that happen to throw off 2% of their energy as light.... Funny, I've gradually converted all my lighting to LED, never really noticed a big difference in kWh consumption - but then I go and put in a 1500 watt heater in the bathroom....10x most of the lighting consumption.....go figure.
You are lucky. Here in London, the fronts of the house are glaring, leaving the road as a silhouette. The problem is that the light SED curve has poor reflective properties. As you pointed out, it does not reflect back illuminating the clouds.
Funny, though, they just finished up a section of the new interstate here during the pandemic and evidently the new LED fixtures were in short supply - when they got them in, some of them actually have a purple-ish tint....and they've been replacing them. Some use a blue LED, some a UV led, with a phosphor coating that produces white from the mixture....someone messed up the recipe....hard to get good help these days...
Yes, whenever someone says "China's fault" I quickly correct them. It's OUR country's 1% executive's outsourcing to sweatshops fault. Rampant globalist capitalist greed to the point it's becoming neo-fuedal.
