M109 is extremely easy to find because it is so near the bright Dipper star Phecda. The core is quite bright so it is easily visible in the guider at 1.5 sec and in the imager at 1-2 sec as well. It has been windy all day, but surprisingly the skies cleared and the wind has subsided so I'm hopeful of getting some good data tonight. My first few subframes look good. I'm deliberately west-weighting the mount after my experience fighting it last night. Maybe this makes some sense with an overloaded mount as mine is. I had a lot of trouble after the meridian flip and just could not seem to reach focus as well or to guide as well. I wonder if I lost collimation at that point? A little breeze came up after midnight as well. I'll have to see what the subs look like. Some of the “after the flip subs” were OK, but ultimately I only used the sharpest subs from before the flip.
Date: 1 May 2013
Subject: M109
Scope: AT8IN + High Point Scientific coma corrector
Filter: None
Mount: CG-5 (Synta motors)
Guiding: 9x50 Finder/Guider + DSI Ic + PHD 1.14.2
Camera: DSI IIc (no chiller, T = ~6 °C)
Acquisition: Nebulosity 3.1.5, no dither
Exposure: 14x300 s (I actually had 38 “good” subs, but I kept only the very best and the image looks better this way to me)
Stacking: Neb 3, bad pixel map, bias included, normalize first, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3 Rotate; Crop; Develop 96.86%; Wipe:Gradient&Color; Develop 95.43%; Contrast; HDR
ptimize; Sharpen; Deconvolute: 3.0 pix; Track; Magic:Shrink 2 pix; Color:Sample star average, Bottom 1.8, Top Full, Sat 426%; Life:Moderate. CS6+Astronomy Tools autotone, Gaussian blurred layer mask to darken and desaturate background, star color enhance; deep space noise reduction; AstroFrame.
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