M1, Crab Nebula, OSC, 21 Nov 2014 (David Dearden)

M1, Crab Nebula, OSC, 21 Nov 2014

Conditions weren't great as a good winter storm is on its way so there were a few high clouds preceding the storm (which still hasn't arrived, but is getting closer as I write). Decided to use my coma corrector to get maximum image size, but of course this is also my most challenging situation for guiding both because of image scale and because the focuser has to be racked way out with the relatively heavy coma corrector in place. Synched from β Tau and the PicGoto as usual was right on. Stopped a few times to refocus; focus kept shifting as the temperature went down, but finally stabilized. I was expecting the mount to bump around 2:30 AM, but it missed so I continued getting decent data until M1 moved into the neighbor's trees. I threw out a bunch of subs due to clouds and some trailing. Chiller still broken but not really needed; started at 8 °C on the CCD and fell from there. I could probably stack these subs with my 19 Dec 2012 data and go a bit deeper.

Date: 21 Nov 2014

Subject: M1, Crab Nebula

Scope: AT8IN + HPS Coma Corrector

Filter: Baader Planetarium Fringe Killer

Mount: CG-5 (Synta motors, PicGoto Simplificado)

Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.3.1l (Win 7 ASCOM)

Camera: DSI IIc no chiller 8 °C

Acquisition: Nebulosity 3.2.1, no dither

Exposure: 50x300 s

Stacking: Neb 3, bad pixel map, bias included, 49 flats, normalize, deBayer & square, trans+rot align, 1.5 SD stack.

Processing: StarTools 1.3.5.289 Crop; Wipe: Aggressiveness 94%, Drop off point 40%; Develop 85.22%; HDR:Core reveal; Color:Scientific, 300%; Life:Moderate; Deconvolute: 3.0 pix; Track 3.2 pix; Magic 2 pix. Photoshop CC 2014 + Carboni Astronomy Tools healing brush; Increase star color; Layer masked levels; Layer masked less crunchy more fuzzy; Astroframe.

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Status	Advanced success
Started	...
Astrometry.net job	418336
PixInsight job	I137QBBOOL46Q41RSK390HEPQQCEW8FW
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	05h34m30s.18
RA (top/left)	05h35m19s.61
RA (top/right)	05h33m36s.27
RA (bottom/right)	05h33m41s.25
RA (bottom/left)	05h35m24s.87

Dec (center)	+21°59′58″.3
Dec (top/left)	+22°10′39″.0
Dec (top/right)	+22°09′22″.5
Dec (bottom/right)	+21°49′17″.8
Dec (bottom/left)	+21°50′01″.4

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