North-America nebula in HaRGB

Object info:
Common name: North-America nebula
Catalog code: NGC 7000
Object type: emission Nebula
Constellation: Cygnus
Object size: 3 degrees
Imaging info:
imaging date: 23 October 2011
Optics: Takumar 135mm f/3.5
Effective focal length: 135mm
Camera & filters: Canon EOS20D modified and 12nm H-alpha filter
Exposure & camera settings: `12x15min@ISO 1600 Halpha and 60x3min RGB
Imaging software: Nebulosity 2.3
Mount: Vixen GP
Guiding details: autoguiding with PHD 12.1 and 550m refractor and DSI I camera
Image processing:
processing date: 24 October 2011
calibration frames: 30 darks and 20 flats from calibration library.
stacking & calibration software: Nebulosity 2.4.1
Postprocessing: Alle done in Nebulosity. In short: I made 2 separate calibrated stacks. One for Halpha and one for RGB. Then the RGB stack was split in 3 separate component files for Red, Green and Blue. Then I aligned and normalized the intensities of the the Halpha stack with the other three. Then a recombine of Halpha, Green and Blue channel and some postprocessing using level and curves.
Local conditions:
Location: Stroe