The Crescent Nebula is easy to find as you can line up the Telrad on Sadr. Although I can't see the nebula at short exposures, there is a distinctive parallelogram asterism that marks its position and makes it easy to find. Unfortunately, conditions are marginal tonight, but it's the first night in about a week we haven't had thunderstorms. There are intermittent high clouds and lots of wind gusts so I don't expect this to turn out too well. Tried PHD Alpha 5 for guiding, but could not calibrate because it kept losing the star for some reason. It's warm tonight. Running the chiller at 2.5 A, 21.5 °C. The wind died down after midnight, but clouds got worse at the same time.
Date: 8 Jul 2013
Subject: NGC 6888, Crescent Nebula
Scope: AT8IN + HPS Coma Corrector
Filter: None
Mount: CG-5 (Synta motors)
Guiding: 9x50 Finder/Guider + DSI Ic + PHD 1.14.2
Camera: DSI IIc (chiller at ~2.5 A, T = 19-20 °C)
Acquisition: Nebulosity 3.1.7, no dither
Exposure: 32x300 s
Stacking: Neb 3, bad pixel map, bias included, normalize first, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3 Crop; Wipe:Color & Brightness; Develop 97.69%; Contrast; HDR
ptimize; Sharpen; Deconvolute: 2.5 pix; Track; Color:Bottom 2.6, Top Full, Sat 400%; Magic:Shrink 2; Life:Heavy with mask, fuzz 7.2 pix. CS6+Astronomy Tools Increase star color; deep space noise reduction; Overlay high pass filter; AstroFrame.
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