This group is all about imaging with narrowband or emission line filters. Many astroimagers live in areas that have significant light pollution. The use of narrowband emission line filters can help overcome the limitations of a bright sky allowing color images such as the one to the right to be taken from a light polluted backyard in a city.
When used to make color images, emission line data can highlight latent structural features in nebulae and give them a unique appearance. The advantages are not limited to color images, many beautiful images have been taken with just a single emission line filter such as Halpha.
The discussion topics of the group include anything relating to imaging with narrowband filters. Image postings are specifically encouraged as are discussion about processing techniques, hardware issues etc.
there can be interference fringing that can occur with monochromatic light in thin optical layers. that might be the source of the problem at the end of the
More experiments to ward off the turkey induced tryptophan trance <G>. Stretched my LRGBs and found just the slightest presence of the same banding in one
FPN = Fixed Pattern Noise it is proportional to signal level: it is what we remove by flat fielding i suspect it is in the RGBs too... so long as you have good