The first is the Gamma Cassiopeiae Nebula, also known as the "Ghost of Cassiopeia" (which I suppose is fitting for October since we celebrate Halloween at the end of this month in the U.S.). This is another foray away from the 100 Best Astrophotography Targets list, so once again I wasn't sure it would be bright enough for me to image. It was, and made a really nice target. It looks to me a lot like the head of a longhorn steer or like the ox skulls that the pioneers in the American west used to leave along the trail, and it even looks a bit like the Greek letter gamma, as befits its namesake star.
Another object that caught my eye on Astrobin, the "Ghost of Cassiopeia" is trivially easy to find because it's in the same field of view as the bright star γ Cas. I deliberately left γ Cas in the frame because that star is what lights up this nebula. Chiller at 2.5 A, 12.5 °C. Clouds rolled in and ended the session early, so I finally shot a new set of darks and created a new bad pixel map to use with this.
Date: 11 Oct 2014
Subject: IC 63, γ Cas Nebula, “Ghost of Cassiopeia”
Scope: Astrotech AT8IN + Antares 0.5x telereducer
Filter: Baader Hα
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, 11.5-9.0 °C
Acquisition: Nebulosity 3.2.1, no dither
Exposure: 20x600 s
Stacking: Neb 3, bad pixel map, bias included, no flats, OSC red channel extract, normalize, square, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3.5.289 Crop; Develop 75%; HDR:Optimize; Life:Moderate; Deconvolute 3.5 pix; Track Grain size 6.0 pix; Magic:Shrink 1 pix. Photoshop CC 2014 + Carboni Astronomy Tools deep space noise reduction, Hα false color; Astro Frame.
I shot my second target last night (actually early this morning). It's one I have done many times in the past, but I've been looking forward to trying the Horsehead in H-α, and last night, after getting home from a late football game (which wasn't too much fun; BYU's team, and particularly their defense, is weak this year), I saw Orion rising and already had the scope outside (to get it out of the way of my daughter and son-in-law's moving activities), so I decided to give it a shot. The weather was good, save for some wind gusts. This session involved lots of new software: OSX Yosemite, a new version of VMWare, and a new build of PHD2. This combination appears to be less stable as I crashed Nebulosity and PHD2 repeatedly, but I guess to really give it a fair shot I need to do a fresh reboot prior to starting the session. I had some trouble getting PicGoto Server to connect (I had to keep hitting the "connect" button repeatedly until it made the connection.) I'm still having problems with my USB connections in general, but that may not be software-related. All that said, this image is dramatically better than the Horseheads I have gotten before. The details in the nebulosity just pop, and at last I can see the curtain-like streaks in the background gas. Now I want to do a wider field of view with my ST-80 refractor.
Date: 19 Oct 2014
Subject: IC 434, Horsehead Nebula
Scope: Astrotech AT8IN + Antares 0.5x telereducer
Filter: Baader Hα
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, 6.5 °C
Acquisition: Nebulosity 3.2.1, no dither
Exposure: 23x600 s
Stacking: Neb 3, bad pixel map, bias included, no flats, OSC red channel extract, normalize, square, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3.5.289 Crop; Autodev; HDR:Optimize; Life:Less=More; Deconvolute 4.0 pix; Track Grain size 3.0 pix; Magic:Shrink 1 pix. Photoshop CC 2014 + Carboni Astronomy Tools Hα false color; Astro Frame.
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