The Crystal Ball Nebula in Taurus
Optics/Mount: CPC1100 with f6.3 Celestron reducer on a Milburn Wedge. Dec antibacklash set to 27/27. PEC on.
Camera: DSI II Pro
Exposure: 42 x 2 minutes luminance, 15 x 2 minutes per color
Date: November 30 - December 1, 2012
Conditions: Seeing 3-4/5, Transparency 3/5. No wind.
Image scale at capture: 1.10 arcsecs/pixel = f/5.7
Guiding Hardware: DMK21AU04.AS, Taurus Tracker III off axis guider. Guiding scale 0.70 arcsec/pixel. 1 second guide exposures.
Guiding Software: PHD. Aggressiveness 100, Hysteresis 0, Minimum Move 1, Max RA 1000, Max Dec 450. Dec set to auto/resist switching. Dithering set to Extreme with Settle < 0.5. Calibration steps 11 x 12.
Guiding performance: FWHM of subs = 4 arc seconds. RMS 0.48 arc seconds, OSC 0.35.
Light pollution: Bortle 8 (white zone)
Filters: Astronomik 2c LRGB
Scale of presentation: 1.1 arcsecs/pixel (full scale)
Capture software: Sequence Generator and Nebulosity 2
Processing: Stacked with Deep Sky Stacker, post-processed with Photoshop CS2