The Crescent Nebula (also NGC 6888, Caldwell 27 or Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light-years away from earth. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 colliding and energizing a slower shell of matter previously ejected.
198 RGB one minute frames, so about 3:15 of integration, no moon. The image above shows a basic processing done on the data. Use the Master Calibration frames provided below (Gain 90).
Below I distribute a package of 163 Narrow band frames of 5mn each, so about 13.6 hours of integration (I initially had about 20 hours but trashed quite a few for clouds, too much moon or other glitches). The frames are evenly distributed between Ha, OII and SII. The SII signal, although weak, is present, and I choose to go after it rather than go deeper into OIII and Ha, as many imager do for this target.
Here is a very nice processing of this dataset.