alt Hacker NewsI wondered if a city-wide synchronised Pulse-Width-Modulation of LED lights could allow astrophotography (or even naked-eye astronomy) to be possible again, with a filter synchronised to the off-cycle.
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coryrc • today at 3:37 AM
No, because the phosphors glow for much longer than human persistence of vision.
fhdkweig • yesterday at 2:59 PM
Los Angeles has the Griffith Observatory. To allow the city to have street lighting while not interfering with the observatory, the lights are sodium vapor lights that emit a specific wavelength that the observatory can filter out. Since LEDs also use specific wavelengths, this could have been done.
I was disappointed that the article didn't mention this, especially because they did mention sodium, but only as a pretty color.
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Using PWM to dim lights should be banned wholesale. Many people, me included, get crazy headaches from the worst lights and mild discomfort from the best ones. It's also completely unnecessary as non-flickering bulbs do exist and are readily available for the same price.