A good test of an efficient light fixture is: Can you see the bulb or light source itself when glancing at any area it's supposed to illuminate? If the answer is yes, the fixture produces glare and is actually decreasing visibility. This has been proven so the "gut feel" argument of the glaring "wall pack" fixture being good security lighting is false. "More is better" is not true when it comes to security lighting. "Effective is better" is true. The downward lighting criterion is of major concern to dark-sky advocates. Light directed upwards into the sky is wasted energy (dollars, resources). On Mon, Jul 14, 2008 at 3:06 PM, <erikhansen@thebluezone.net> wrote:
To start it off: The basic idea is when you shield and direct the light downward you can use lower watt lights and save energy and reduced sky glow. The reduced glare also enhances security by improving your ability to see in low light conditions. The harsh light produces "blind spots" and hampers night vision.