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The Hole in the Trees Skybox | all galleries >> Deep Sky >> Planetary Nebulae > Abell 82
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Abell 82

PK 114-04.1 in Cassiopeia

Optics/Mount: CPC1100 with f6.3 Celestron reducer on a Milburn Wedge. Dec antibacklash set to 27/27. PEC on.
Camera: SXVR-H694
Exposure: Total exposure time about 17 hours; 16 x 20 mins Ha, 32 x 20 mins OIII, plus 12 x 2 mins each RGB. All bin 1x1.
Filters: Astrodon 5nm Ha, 3nm OIII, and Type IIi RGB
Date: Data was collected over 15 nights from August to October 2015
Imaging automation and capture: Sequence Generator Pro

Guiding Hardware: ASI120MM, Celestron off axis guider. Guiding scale 0.92 arcsec/pixel. 1 second guide exposures.
Focusing: Rigel Systems GCUSB/nStep on stock C11 focuser
Guiding Software: PHD2. RA aggressiveness 55, hysteresis 0, Minimum Move 1.4 arcsecs, Max RA 1000, Max Dec 600. Guiding unbinned with ZWO connection. Dec set to hysteresis. Dithering set to Extreme with Settle < 1.2.
Guiding performance: FWHM of subs about 1.4 arc seconds, RMS in PHD about 0.75 arcsecs.
Light pollution: Bortle 8 (white zone, NELM about mag 4.5)
Image scale at capture: 0.6 arcsecs/pixel = f/5.7
Scale of presentation: 0.9 arcsecs/pixel
Processing: Bias, darks, and flats. Stacked and processed with PixInsight, with a few minor modifications in Photoshop. The nebula is a bicolor Ha/OIII/OIII, with Ha as luminance, except for the nebula extensions, which use Ha/OIII/OIII as luminance. The luminance and RGB stars were layered together in Photoshop.

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