I was a little hesitant to try NGC 891 because I already have a pretty good image of it from 2 years ago, but I decided to see if I could do better. Intermittent wind gusts, but very clear. Synched on γ1 Andromedae and the PicGoto put NGC 891 in my imaging field of view easily. Chiller at 2.5 A, falling from 18 to 11 °C through the night. I must have timed things just right because I went to bed and my imaging session ended just before the mount bumped, while I got a good night's sleep! I tried a bit more sophisticated deconvolution on this image than usual; I masked so I aggressively deconvoluted the dust lane but didn't touch the outer fringes of the galaxy. I probably should have masked the stars a bit more because I got some ringing, so maybe I'll redo the processing.
Date: 24 Sep 2014
Subject: NGC 891, Outer Limits Galaxy
Scope: AT8IN
Filter: Baader Fringe Killer
Mount: CG-5 (Synta motors, PicGoto Simplificado)
Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.3.1 (Win 7 ASCOM)
Camera: DSI IIc chiller at 2.50 A, 18-11 °C
Acquisition: Nebulosity 3.2.1, no dither
Exposure: 62x300 s
Stacking: Neb 3, bad pixel map, bias included, no flats, normalize first, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3.5.289 Crop; Wipe:Color & brightness 75%; AutoDev with ROI; HDR
ptimize; Color:Scientific, 250%; Deconvolute auto mask+block outer parts of galaxy 3.5 pix; Life:Less is more; Track Grain size 5.9 pix; Magic:Shrink 1 pix. Photoshop CC 2014 + Carboni Astronomy Tools Healing brush; Increase star color; Astro Frame.
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