As an amateur astronomer and someone who enjoys the simple pleasure of a sky full of stars, this image always makes me sad. It is a good indicator of just how out of control light pollution has gotten. Light pollution robs us of our view of the stars in the night sky. Also makes our flashlights look much less impressive because it is so darned bright outside at night. In fact, if you really want to be impressed by your greenie, try it out a couple hundred miles away from the nearest city. Even an unmodded 5mw unit looks really impressive.
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What you see in the picture represents a tremendous waste of light and energy because you are seeing light that is simply going up into space and not serving any useful purpose (other than to make cool satellite images). This is primarily the result of crappy lighting fixture designs that spew light out in all directions. The ironic thing about all this is that the lighting is actually less effective (less safe) because the user has a direct line of site with the light source. Imagine how ineffective and annoying our flashlights would be if the light source were not hidden behind a housing and reflector. Kind of like trying to walk around in the woods at night using a bare Side Emitter LS as your light source. When possible, light should always be directed only towards the area it is intended to illuminate and nowhere else.
Fortunately, newer streetlight fixtures that prevent light from going upwards (full cutoff housings) are being developed and implemented. I find it much easier to see the areas these lights are intended to illuminate because I am not distracted by the direct glare of the light source. Many communities have started using these new fixtures with great results. You can even use a lower wattage bulb because the light is being focused only where it is needed.
Some of the results of improper lighting techniques:
- less effective lighting
- wasted energy and higher municipal electric bills (wasted tax dollars)
- light trespass (lots of unwanted light coming into our homes at night)
- fewer stars visible in the sky at night
- less fun with our Flashaholic toys
For more info about this subject, check out this site:
web page
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Sorry Photon, I did not intend to hijack your thread, but every time I see folks discussing this image I feel compelled to discuss what it truly represents.