M100 & Vicinity, OSC (UHC-S), 12 May 2016 (David Dearden)

M100 & Vicinity, OSC (UHC-S), 12 May 2016

Another night of excellent conditions, and another chance to try the full automated, temperature-adjusted focusing routines, this time without the coma corrector (so everything should be a little easier, but I did have to establish the focus position for this combination). Meridian flip came pretty early and I don't yet know how to easily change the center of the field of view, so after flipping M100 was dead center and I had to manually reposition it where I wanted it. I'm still getting some drift that I think is flexure, but it wasn't as bad. Overall, I'm happy with the image, which I think is better than the one I got the last time I visited this field of view.

Date: 11-12 May 2016

Subject: M100

Scope: AT8IN

Filter: Baader Planetarium UHC-S

Mount: EQ-6 (EQMOD)+PEC

Guiding: Orion ST-80 + Antares 0.5x focal reducer + DSI Ic + PHD 2.6.1.1 (Win 7 ASCOM)

Camera: DSI IIc, no chiller CCD 5 °C

Acquisition: Sequence Generator Pro 2.5.1.10 with Nebulosity 4.0.4 ASCOM camera driver

Exposure: 24x600 s

Stacking: Neb 4, bad pixel map, bias included, 33 flats, match histograms, trans+rot align, Neb 4 40-60%tile stack.

Processing: StarTools 1.4.316: Crop; Wipe; Develop: 86.44%; HDR

ptimize; Color:Scientific, 200% saturation, red bias reduce 1.35; Deconvolute: 2.6 pix; Track: Smoothness 87%, 4.5 pix; Magic, shrink 1 pix. Photoshop CS6 + Astronomy Tools: Deep space noise reduction; Levels; Increase star color; layer masked unsharp mask to bring up contrast in dust lanes; Astroframe.

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Distribution of astrophotographers

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	Distinct awarded users	Total awarded images
Image of the day
Top picks
Top pick nominations

Distribution of subject types

This table shows the distribution of awards per subject type, compared to the popularity of images of that subject type.
	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
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Landscape

Distribution of data sources

This table shows the distribution of awards per data source, compared to the popularity of images acquired from that data source.
	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown

The “AstroBin Image of the Day and Top Picks”, or IOTD/TP, is a long-running system to promote beautiful, interesting, peculiar, or otherwise amazing astrophotographs, with a focus on technical excellence. Learn more.

Submitted The date and time when you submitted this image for IOTD/TP consideration.	...
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Status	Basic failed
Started	...
Astrometry.net job	1074429
PixInsight job	n/a
PixInsight queue size	n/a
PixInsight stage	n/a

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