Darky Sky lighting question (output, buzz, flicker)

[Chuck]

Greetings all!

My wife and I are about to replace a bunch of our cheap outdoor house lights, and came across the "Dark Sky" variety such as this one:

Our first question pertained to amount of light output. We don't have huge demands in this area (we have been tolerably happy with our meager "single yellow bug light bulb jelly jar" variety for eight years), but we wonder if the hooded "dark sky" variety of fixtures essentially save the night sky by producing almost no light at all.

Then we got concerned about the type of bulb these lights use (13w Spiral G24q-1 4-Pin with 120V LVS Electronic Ballast). I presume these kinds of lights are energy efficient, but I generally loathe flourescent bulbs. I associate flouresecent fixtures with hum, flicker, headaches, and a sterile cold lighting spectrum. I have flourescent lights in my office, and I am so flourescent-aversive that I absolutely never turn them on. I have no doubt there have been improvements in flourescent technology over the last couple decades, but would a hyper-sensitive person like me still detect a hum or flicker?

We live WAY out in the country where there are neither lights nor noises emanating from a nearby city or neighbors. While this fact is what drove us to consider the "dark sky" options, it also means that even minor hum and flicker is going to be noticeable.

Does "Dark Sky" lighting always mean "flourescent" or are there incandescent "Dark Sky" types of lighting fixtures we should consider? The cost savings associated with flourescent do not interest us; if we want to save money, we are happy to turn the lights on for fewer hours per year.

Thanks in advance for any suggestions or guidance!

Chuck

[JimL]

Dark Sky is telescope star gazing friendly. Or for looing at the space station move overhead.

By the way, in a few years, the new addition to the space station will mean you can spot it moving overhead in the DAYTIME!!!

And the electronic ballast will stop all the buzzing. I wouldn't have anything else.

Definiely a winner.

[Tim Killian]

Good for you. I wish more people would take the time to consider how their outdoor lights affect other people and then select fixtures which conserve both energy and the natural beauty of the night sky. Dark sky lighting generally means using the minimum light needed, and aiming or shielding lights so they illuminate the ground on your property, not the sky or a neighbor's house. If you don't like CFL bulbs, go ahead and use a regular incandescent fixture. BTW there are now CFL "bug" lights with the yellow colored glass. I have two of them and don't notice any noise or hum.

[TKM]

>

Thanks on behalf of the International Dark Sky Association for being sensitive to the night environment and the IDA goal of making and keeping the beauty of the stars visible for all. Here are the answers to your questions:

Dark sky fixtures are designed to direct their light toward the ground with minimum glare, stray light and, of course, light into the sky. What you will notice from such fixtures is that they don't "broadcast" light everywhere including into your bedroom windows. The amount of light where you need it (on the ground, steps, etc.) should be more than sufficient.

The bulb in your fixture is a type of compact fluorescent lamp or CFL. Such bulbs are 3-4 times more efficient than standard incandescent bulbs and last 10 times longer. These days the color of CFLs can be so similar to standard incandescent bulbs that most people can't tell the difference. Just be sure to use "warm" or 3000K CFL bulbs. Yellow "bug light" CFL bulbs are fine too.

CFL bulbs do not hum or flicker and are quite different from the fluorescent lamps of old. Too bad that we still use the term fluorescent.

Good "dark-sky lighting" can use any type of bulb. The term refers to how the light and glare are controlled rather than to the type of light source. Do check out the IDA web site (above) for more information.

Terry McGowan IDA Board Member