NGC 891

Lum - 28 x 15 minute subs (no binning, -20c)
R - 7 x 10 minute subs (2x2 binning, -25c)
G - 7 x 10 minute subs (2x2 binning, -25c)
B - 7 x 10 minute subs (2x2 binning, -25c)

Total exposure is 630 minutes or 10.5 hours. The data was captured with a 16-inch f/8.9 RCOS on a Paramount ME, SBIG STL11000M CCD with Astrodon LRGB filters, field flattener located at the Sierra Remote Observatories outside of Fresno, California at 4600 feet elevation.

All image calibration (Lights, Bias, Darks and Flats) and processing was done in PixInsight. RGB files used Dynamic Background Extraction, Photometric Colour Calibration, ArcSinH stretch followed by mild Histogram Transform stretch, HDR Transform, Noise Reduction (ACDNR) and mild saturation increase. Luminosity used Dynamic Background Extraction, ArcSinH stretch followed by mild Histogram Transform stretch, HDR Multiscale Transform and Noise Reduction (ACDNR). LRGB was then created from processed RGB and Lum data.

Image Credit: Steve Mastellotto and Paul Mortfield