Set F, Good Lighting Slide Set:

Set F

Text slide: An alternative IDA slide.
Text slide: Light Pollution, Radio Pollution, Space Debris
A negative photographic image of the sky, taken with the Schmidt telescope at Siding Spring Observatory, in eastern Australia. The tracks are due to passing space debris! It is nearly impossible to take photographs with this or similar telescope with getting one or more such tracks. Most objects in Earth orbit are, in fact, space junk, space debris, and not functioning satellites.
Text slide: Urban Sky Glow
Text slide: Urban Sky Glow: A Serious Threat to Astronomy and the Environment
Text slide: What Can Be Done: ...
Text slide: Solutions I: ...
Text slide: Solutions II: ...
A schematic chart of the differences between good and bad lighting.
A chart illustrating that not all reflected light from the ground gets into the sky. Trees and buildings block light, and multiple reflections are common. Remember that about 80 to 90 percent of the light is absorbed at each such reflection in most cases.
A color coded (by computer analysis) illustration of the sky glow above the city, looking from a distance toward the city. Red is the brightest, tapering off as one looks further above the city.
An "all-sky" photo of the sky, from a location south of Tucson AZ. The sky glow near the horizon is from the city, a city of about 700,000 inhabitants. The sky is still dark at locations rather near the city, and at Kitt Peak National Observatory, about 35 miles to the west, the increase above the natural background is less than 10 percent.
A decorative street lighting fixture, at Chinatown in San Francisco. Clearly, such a fixture is far more for decorative purposes than for effective street lighting. As such, it should have as low a wattage lamp in it as feasible, so that it looks nice and is not glary.
Effective advertising lighting. This sign at the Stardust, in Las Vegas, has won several awards for its effectiveness. It is not necessary to have the maximum amount of light that one can afford in order to be effective. In fact, such "overkill" is not good lighting in any situation, and would be counterproductive to any quality advertising.
An aerial view of one of the major streets in Tucson AZ. Most all of the lighting that we see is advertising lighting, as all of the major street lighting in Tucson uses full cutoff fixtures. Clearly, there is a lot of wasted light from such advertising signs. This street is a prime example, as are many streets in most cities, of the garish, harsh, poor lighting so common in most of our cities. We can and should do better.
An effective sign. The dark background with lighter lettering is most effective, as it is in many signs we see about us. The only white background part is to highlight the Emergency lettering.
An excellent full cutoff LPS lighting fixture, used for a walkway at a major university.
An example of a decorative "street lighting" fixture, on the right. It has a low wattage lamp in it and looks quite attractive at night. The lighting level is so low that there is no glare. But it puts only a little light on the ground, of course. So the full cutoff street lighting, above and set back from the road, is used for the actual street lighting. A very nice combination, done with good design thought.
Is this what we mean by Light Pollution? Humor works well in all talks, and slides that can offer some are most useful in any set. So is dialog to accompany the slides, and indeed, humor is an essential part of most any successful talk.
An astronomical object, also a source of light, as are the Sun and the Moon and the stars. This one is M16, or NGC 6611, or the Eagle Nebula. It contains a number of hot, young stars (as stars go, only a few million years old) and glowing hydrogen gas which is emitting light on its own due to the intense ultraviolet energy output from the hot stars. There is much we can learn from the careful study of the universe about us; we must insure that such studies will be able to continue into the indefinite future. In addition, the contemplation of the universe is a most impressive thing to anyone who views it from a prime, dark sky site. It is not just astronomers who love the universe and are inspired by it. It is all of us.