In the February 2015 issue of Astronomy, amateur astronomer Gordon Haynes described the journey he took to become the premier astroimager he now is.
Light pollution in Haynes’ neighborhood makes it hard for him to image in LRGB, so he did some research and discovered narrowband imaging. Simply put, narrowband imaging involves shooting through filters that transmit only a small (narrow) part of the light striking them. The three most popular filters are Hydrogen-alpha, Oxygen-III, and Sulfur-II. When Haynes processes the data he collects through the filters, he assigns each a “normal” color channel — red, green, and blue — and then combines them to create a final image.
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