Sh2-188 - The Dolphin Nebula (lefty7283)

Sh2-188 - The Dolphin Nebula

I got inspired by [a recent Astrobin post](https://www.astrobin.com/pa8cu6/) and decided to photograph Sh2-188, although my image isn't nearly as good as the one I saw on AB. This nebula was created by an extremely fast moving star, and the bright part is the bow shock interacting with the interstellar medium. There is also a very diffuse and faint trail of material on the opposite side, but I didn't want to stretch it that much [as it brought out a lot of noise](https://i.imgur.com/gn1DzHw.png). I've also made a [starless version using StarNet++](https://i.imgur.com/Fb1YQcj.jpg) to help show some of the dimmer nebulosity. This is probably the faintest nebula I've shot, [especially when looking at the unprocessed Oiii stack](https://i.imgur.com/RANN8MI.png). Captured on September 22nd, 23rd, 25th, and 26th, 2019 from a bortle 7 zone.

**Equipment:**

* 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

* Agena 50mm Deluxe Straight-Through Guide Scope

* ZWO ASI-120MC for guiding

* Moonlite Autofocuser

**Acquisition:** 14 hours 12 minutes (Camera at Unity Gain, -15°C)

* Ha- 69x360"

* Oiii- 73x360"

* Darks- 30

* Flats- 30 per filter

**Capture Software:**

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

**[PixInsight Processing](https://i.imgur.com/M0QPCvi.png):**

* BatchPreProcessing

* SubframeSelector

* StarAlignment

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

* ImageIntegration

* DrizzleIntegration (2X, VarK 1.5)

* DynamicCrop

* AutomaticBackgroundExtraction

* DynamicBackgroundExtraction

* TVG/MMT/MLT Noise Reduction

* LinearFit Ha to Oiii

* PixelMath to combine channels

* R= Ha

* G= 0.35 * Ha + 0.65 * Oiii

* B= 0.2 * Ha + 0.8 * Oiii

* AutomaticBackgroundExtraction

* ArcsinhStretch

* HistogramTransformation

* [Curve](https://i.imgur.com/Fyb34PJ.jpg)Transformations

* LRGBCombination with extracted L channel as luminance

* LocalHistogramEqualization

* MLT Noise reduction

* More curves

* MorphologicalTransformation to reduce star sizes

* MMT Noise reduciton

* FastRotation 180 degrees

* Even more curves

* Resample to 85%

* Annotation

Narrowband imaging
Sharpless2 Objects
/r/astrophotography
ZWO ASI1600MM/QHY163M
Suburban Astrophotography

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

	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape

	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

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Status	Advanced success
Started	...
Astrometry.net job	2983851
PixInsight job	921G6Z00XQVUK5ZNRDMRZ1H0U7H3QBEM
PixInsight queue size	n/a
PixInsight stage	n/a

RA (center)	01h30m33s.299
RA (top/left)	01h35m26s.456
RA (top/right)	01h34m28s.841
RA (bottom/right)	01h25m27s.716
RA (bottom/left)	01h26m48s.896

Dec (center)	+58°25′08″.47
Dec (top/left)	+57°40′20″.68
Dec (top/right)	+59°15′52″.46
Dec (bottom/right)	+59°09′10″.12
Dec (bottom/left)	+57°33′56″.13

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