NGC 4236 - Barred Spiral Galaxy in Draco (lefty7283)

NGC 4236 - Barred Spiral Galaxy in Draco

NGC 4236 is a high declination (dec +70) galaxy in Draco. I wanted to shoot a larger non-messier galaxy in that region while waiting for the summer targets to rise above my house, and found this one in stellarium. It has a pretty low surface brightness which meant I had to sink a lot of exposure time into it. Now that the summer targets are up at astro dark I'm moving on from this galaxy. Captured on May 9, 11, 15, 30, and June 1, 2, 6, 7, and 12th, 2020 from a Bortle 6 zone.

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**[Equipment:](https://i.imgur.com/6T8QNsv.jpg)**

* TPO 6" F/4 Imaging Newtonian

* Orion Sirius EQ-G

* ZWO ASI1600MM-Pro

* Skywatcher Quattro Coma Corrector

* ZWO EFW 8x1.25"/31mm

* Astronomik LRGB+CLS Filters- 31mm

* Astrodon 31mm Ha 5nm, Oiii 3nm, Sii 5nm

* Agena 50mm Deluxe Straight-Through Guide Scope

* ZWO ASI-120MC for guiding

* Moonlite Autofocuser

**Acquisition:** 22 hours 22 minutes (Camera at Unity Gain, -15°C)

* Ha- 53x300"

* Lum- 117x120"

* Red- 24x60""

* Green- 24x60"

* Blue- 24x60"

* Darks- 30

* Flats- 30 per filter

**Capture Software:**

* Captured using [N.I.N.A.](https://nighttime-imaging.eu/) and PHD2 for guiding and dithering.

**PixInsight Processing:**

* BatchPreProcessing

* StarAlignment

* [Blink](https://youtu.be/sJeuWZNWImE?t=40)

* ImageIntegration

* DrizzleIntegration (2x, VarK=1.5 used on luminance only)

* DynamicCrop

* DynamicBackgroundExtraction 2X

**Luminance**

* Deconvolution

* TGV+MMT noise reduction using Darkarchon's script

* ArcsinhStretch

* HistogramTransformation

**RGB**

* LinearFit to green

* ChannelCombination

* AutomaticBackgroundExtraction

* NBRGBCombination to add in Ha

* PhotometricColorCalibration

* SCNR

* HSVRepair

* ArcsinhStretch

* HistogramTransformation

* [Curve](https://i.imgur.com/TpfgmyI.jpg)Transformation to boost saturation

* LRGBCombination with Luminance

* ACDNR

* Several curves for adjusting lightness, colors, and saturation (some with range masks)

* LocalHistogramEqualization

* MorphologicalTransformation to reduce star sizes

* MMT noise reduction

* Annotation

* Resample to 85%

/r/astrophotography
ZWO ASI1600MM/QHY163M
Suburban Astrophotography
Fast Newtonians

	Distinct awarded users	Total awarded images
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	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
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Star trails
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	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
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Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown

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Status	Advanced success
Started	...
Astrometry.net job	3847116
PixInsight job	A79G8LD3UPC6DH0YQIIQ9O7W2TYQ09TU
PixInsight queue size	n/a
PixInsight stage	n/a

RA (center)	12h16m43s.206
RA (top/left)	12h24m49s.739
RA (top/right)	12h18m53s.646
RA (bottom/right)	12h08m21s.518
RA (bottom/left)	12h14m41s.689

Dec (center)	+69°27′47″.40
Dec (top/left)	+69°06′55″.99
Dec (top/right)	+70°14′12″.43
Dec (bottom/right)	+69°47′10″.15
Dec (bottom/left)	+68°41′14″.33

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