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BigJim
2004-Jan-14, 04:17 AM
Say that you were to have a polarizing filter over a telescope. Now also suppose that it is night, but there is a bright light directly over the telescope. Disregarding the fact that the bulb, etc. would be in the way, if the light from the bulb were polarized in a direction perpendicular to that of the filter, would it have an effect on the telescope's abillity to receive light? In other words, could you see anything in the sky?

mike alexander
2004-Jan-14, 04:56 AM
I don't think very much, at least in practice. The scope polarizer would cut down incoming light by itself, and polarizers are not 100% effective.

On the other hand, I'm sure you could see the moon (obvious), maybe a bright planet.

Charlie in Dayton
2004-Jan-14, 07:32 AM
Depends. Is the incoming light polarized? Is the polarity matched to the polarizer? If not, what's the angle?

I remember reading something in a story from my long-lost childhood that moonlight is polarized.

Yesnomaybepossibleperhaps?

BigJim
2004-Jan-15, 07:07 PM
Depends. Is the incoming light polarized? Is the polarity matched to the polarizer? If not, what's the angle?

The lightbulb is polarized at a angle perpendicular to that of the of the polarizing filter. As I understand it, it shouldn't cause any interference.