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What is the law? What are people legally required to do?
by Naac 5y ago
What is the law? What are people legally required to do?
- dheera 5y agoMost light pollution laws limit outdoor lighting fixtures and require them to only emit downwards and not upwards.
- wongarsu 5y agoProbably the most noticable change in recent years is the replacement of mercury-vapor streetlights with the yellow-orange sodium-vapor lights, or with orangish LEDs (although some use blueish LEDs that are not that great for light pollution). In terms of actual legal requirements, Bavaria prohibits sky beams/searchlights directed upwards, and the illumination of facades of public buildings between 11pm and morning.
- terramex 5y agoWhile switching to LEDs can improve naked eye view of night sky, it sometimes negatively impact amateur astrophotography as mercury and especially sodium lamps have narrow emission spectrum and it can be filtered off using optical bandpass filters. LEDs light have much wider spectrum and cannot be filtered off.
- acwan93 5y agoSan Jose, California does this for the Lick Observatory at Mt. Hamilton, although I think they're switching to blueish LEDs. The sodium-vapor lights are frequently mistaken as yellow traffic lights though, in my experience.
- NavinF 5y agoyellow-orange sodium-vapor lights are terrible for anyone who's not an astronomer. The sharp output spectrum prevents humans from seeing color
- Dylan16807 5y agoDo you really need color vision in the middle of the night? Even with wide spectrum lights, turning them down is going to suppress colors anyway.
- deleted 5y ago[deleted]
- tut-urut-utut 5y agoActually, I stand corrected, there's no federal German law about light pollution. It's left to different federal states, and most of them incorporated regulations about light in their legislation. I can't find an English text but the document from the federal parliament below summarizes the legal state of the topic in Germany. https://www.bundestag.de/resource/blob/632966/7ba7c4cd1cfef87380d58376f1c2f165/WD-7-009-19-pdf-data.pdf https://www.bundestag.de/resource/blob/632966/7ba7c4cd1cfef8...