Quote:
Originally Posted by kittenshark
I'd imagine LEDs would be worse.
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I don't think so.
The existing poorly designed HPS (the ubiquitous orange streetlamps) have the bulbs protruding under the face of the fixture which spreads more light upwards.
Most LED fixtures have a flat face and spread far less light upwards. But many LED streetlamps have the wrong color temperature, too white and too much blue in it. Recent streedLEDpoles however, have 3000K LEDs in it which is not so harsh and scatters less as they have less blue light.
And LED is not completely broadband: the blue counterpart has a spike and the area between 480-500nm is considerably dimmer which is just the Hbeta and OIII area. The Halpha output is also rather low.
Moonlight is far worse as that has a real broadband spectrum and has also more blue light in it as it has a color temperature of 4000-5000K.
This picture shows the spectrum of a 5000K LED compared to sunlight (and moonlight), a 3000K LED is considerably dimmer in the blue.
This all does not say that city councils have to be very aware of the choice of the proper luminaries, and should also consider smart lighting, which means, that much more motion detectors should be installed for security lighting instead of all night on lighting.
And Brisbane is not the worst: Sydney and Melbourne are larger and have more LP, and in the rest of the southern hemisphere, Johannesburg or Sao Paulo are far worse.
Australia is one of the darkest countries in the world with only 40 million people in an area as large as the USA and lets keep in so dark !
Here in the EU is is far worse !