I use asi 1600mm c Pro and have been using gain zero (bortle 4 skies) and can run 2, 3 or 4 min exposure on lrgb for good dynamic range but with my Ha I find I need to turn up gain to 75 offset 15(as a guess) to get good mean readouts without having to have a ten minute long exposure.. Mainly as a plane will ruin some of them! ✈️

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