Another image of M 13. This time acquired with the 355mm Newtonian and ASI 174MM with no filters. Initially the shot was intended as a test for the Baader MPCC, (finding the correct distance from the sensor) but after a few minutes of testing and finding out that I’m missing some adapters, I’ve decided to take a longer image series.
The shot is a stack of 1200 frames, each a 3 seconds exposure (gamma to 70, gain at 300, no darks or flats – the synthetic flat was very hard to create). The seeing was mostly poor, and the decreasing altitude of the cluster didn’t help either (about 40 degrees at midpoint into the acquisition). Plus…the eternal light pollution and some wind. I really must go to a dark-sky location…soon! Until that moment comes, I’m counting the stars in the following image: