Re:The argument for switching off lights at night
by throw0101a on Sunday July 25, 2021 @08:45PM
(#27954303)
A lot of lamps in the past had little cut-off, sometimes sending light straight up.
New designs, especially Dark Sky approved ones, tend to concentrate a lot more light straight down (0˚), with some spill over over out to 60˚ to the side, but having a hard-ish cut-off by 80˚.
If you simply do a 1:1 replacement of street lamp heads, the new more narrowly-focused units will of course not "splash" light as far—but who wants to install new poles for the new design?
New designs, especially Dark Sky approved ones, tend to concentrate a lot more light straight down (0˚), with some spill over over out to 60˚ to the side, but having a hard-ish cut-off by 80˚.
If you simply do a 1:1 replacement of street lamp heads, the new more narrowly-focused units will of course not "splash" light as far—but who wants to install new poles for the new design?