Asked by Janet Lawrence
Light pollution filters reduce sky glow by only allowing particular wavelengths of light through them. Light emitted by street lamps, such as high-pressure sodium streetlights are rejected, allowing you to see more targets in the night sky.
You should remember that these filters would not solve the problem of light pollution, especially in very well-lit areas. They are only really capable of reducing it and even then, you may not be able to see faint and diffuse objects such as galaxies without a high-quality telecope.
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