Flashlight Lamp

red flashlight to observe the stars work in lampposts?

I know that with a red lantern, as the paint or nail polish normal red lanterns and all that helps you view the night sky better, because .. I do not know, the red wavelength or something? So I wondered, could work in all street lights and lamp posts outside? If you turned on the light of a different color than yellow, would it still be safe .. There is a way to do this that is safe and light pollution to use?

Astronomers use red lanterns at night because red light is less damaging to the dark adaptation of the eyes, so that when you turn on the flashlight and watch the sky, you will not have to wait until your eyes recover. The red light is still light, however, so the use of lights red street would not help the light pollution. For astronomical research, it is useful if the night light emits light only in a narrow band spectrum, since it is easy to filter out. Therefore, astronomers often recommend using lamps Low pressure sodium, whose light is limited to a narrow band around 589 nm wavelength.

Flashlight Lamp

Flashlight Lamp