M1, Crab Nebula, Hα, EQ-6 First Light, 26 Dec 2015 (David Dearden)

M1, Crab Nebula, Hα, EQ-6 First Light, 26 Dec 2015

I finally bought an astrophotography-rated mount, a Skywatcher EQ-6, in early December (it was on sale for a good price), but have not had time or clear skies to try it out until last night. So this is a first-light image with the new mount, controlled with EQMOD/EQASCOM/Cartes du Ciel. This is a whole new experience for me. It is especially nice to have full computer control with full slewing capabilities. I aligned on 4 bright stars all over the sky, found the target easily, and started imaging. I imaged up to the meridian and hit the meridian limit, stopping the mount. I then performed a meridian flip and had the target in the field of view, recentered, and resumed imaging. I set the park timer and went to bed. All of this from within the comfort of my warm living room (and it was bitterly cold outside, so it was nice). Woke up in the morning to find the mount parked as commanded. I haven’t applied any PEC yet, but the guiding performance was far superior to what I’ve been seeing with my old CG-5. I have a lot to learn about how to best use this mount, but I’m really impressed so far. The main thing that went wrong on this image was the remote focuser failed (I suspect a loose linkage or bad connection, but haven't had time to troubleshoot yet).

Date: 26 Dec 2015

Subject: M1, Crab Nebula

Scope: AT8IN

Filter: Baader 7 nm Hα

Mount: EQ-6 (EQMOD)

Guiding: 9x50 mm finder/guider + DSI Ic + PHD 2.5.0.8 (Win 7 ASCOM)

Camera: DSI IIc, no chiller CCD -10 °C

Acquisition: Nebulosity 4.0.4, no dither

Exposure: 46x600 s

Stacking: Neb 4, bad pixel map, bias included, 33 flats, extract R channel, match histograms, square, trans+rot align, 40-60-tile stack, Catmull-Rom spline 2x resize

Processing: StarTools 1.4.305 + CS6 Astronomy Tools: Crop; Wipe; Develop: 84.75%; HDR: Optimize; Deconvolute: 3.5 pix; Track: Smoothness 88%, 4.5 pix; Levels; Astroframe.

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Status	Advanced success
Started	...
Astrometry.net job	894698
PixInsight job	W0QK5H4F8Z0FPJ94Z65I99SKMQ58OUAM
PixInsight queue size	n/a
PixInsight stage	n/a

RA (center)	05h34m32s.21
RA (top/left)	05h35m25s.28
RA (top/right)	05h33m41s.46
RA (bottom/right)	05h33m39s.78
RA (bottom/left)	05h35m23s.61

Dec (center)	+22°02′05″.1
Dec (top/left)	+22°11′13″.6
Dec (top/right)	+22°11′46″.9
Dec (bottom/right)	+21°53′04″.8
Dec (bottom/left)	+21°52′18″.1

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