Finally got a chance to finish my 3 globulars mini-project. Once again had trouble plate solving; perhaps the close-packed stars of the cluster overwhelm the solving algorithm. So I manually framed the image and proceeded. Had some problems with failed downloads again, but worked around them. M13 did not disappoint; this image is far better than my best previous M13. Interestingly, I think the drizzle stack turned out better than non-drizzled, which is not usually the case when I image at this scale.
Date: 24 Jun 2016
Subject: M13, Great Hercules Globular Cluster
Scope: AT8IN+High Point Scientific Coma Corrector
Filter: Baader Planetarium Fringe Killer
Mount: EQ-6 (EQMOD)+PEC
Guiding: Orion ST-80 + Antares 0.5x focal reducer + DSI Ic + PHD 2.6.1.1 (Win 10 ASCOM)
Camera: DSI IIc, no chiller CCD 15 °C
Acquisition: Sequence Generator Pro 2.5.1.16 with Nebulosity 4.0.4 ASCOM camera driver
Exposure: 32x120 s
Stacking: Neb 4, bad pixel map, bias included, 33 flats, match histograms, trans+rot align, Deep Sky Stacker 2x drizzle, 1.5σ κ-σ stack.
Processing: StarTools 1.4.316: Crop; Wipe; Auto Develop; HDR
ptimize; Color:Scientific, 200% saturation; Deconvolute: 3.5 pix; Track: Smoothness 87%, 8.9 pix;. Photoshop CS6 + Astronomy Tools: Deep space noise reduction; Layer masked levels to remove some vignetting; Increase star color; Astroframe.
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