The North America Nebula is easy to find with the Telrad relative to Deneb (and at this imaging scale, finding is super easy). I'm doing the ridiculous thing of imaging through my finder/guider with an Antares 0.5x focal reducer (which actually yields about 0.6x); there is obvious aberration around the edges but no vignetting. Conditions are marginal again tonight with clouds expected soon and lots of gusty wind currently. However, at this imaging scale I can have huge guiding errors and they still won't show up. Chiller at 2.5 A, 20.5 °C currently. The effects of the cheap optics are obvious as aberrations around the edges, which I worked hard to try and mitigate. Overall I’m pleased at what I was able to get from this with such an inexpensive setup.
In the B revision I used Autodev and a bit less "lens" correction, a bit higher saturation leaving more on the bottom, with a bit more manual smudge tool touch-up.
In the C revision I did a bit of additional smudge tool work to touch up a few more distorted stars.
Date: 10 Jul 2013
Subject: NGC 7000, North America Nebula
Scope: 9x50 Finder/Guider + Antares 0.5x Focal Reducer
Filter: Baader Planetarium UHC-S
Mount: CG-5 (Synta motors)
Guiding: AT8IN + HPS Coma Corrector + 0.5x focal reducer (bad, I know!) + 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: 30x300 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 93.74%; Contrast; HDR
ptimize; Sharpen; Deconvolute: 3.0 pix; Track; Color:Bottom 2.0, Top Full, Sat 400%; Lens:Linked Curvature 85.29%; Magic:Shrink 1 on all stars, Tighten 2 on all stars, Shrink 4 on large stars, Tighten 27 on selected stars with halos; Life:Moderate. CS6+Astronomy Tools Increase star color; AstroFrame.
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