One of the most significant challenges of astro-photography is the problem of light pollution. Even if you’re dozens of miles away from a major metropolitan area, there’s a good chance the light pollution of orange sodium vapor city street lamps will affect the outcome of your photograph.
There are a few ways to get around this in post-production, but most of them involve adding a virtual graduated filter and adjusting the color balance to fix the problem. What if you could simply add a physical filter on your lens to fix the problem in-camera, where the data is originally gathered?
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