Horsehead Nebula (HaRGB) (Linda)

Horsehead Nebula (HaRGB)

Link: https://lindasastronomyadventures.space/?p=11797

I'd been putting off the horsehead for a long time because I knew Alnitak's Evil Glare would be an issue but this year was finally the one where I picked up the gauntlet it threw down and tried to have a go at it. Sure enough it turned out to be deceptively challenging. While Alnitak wasn't in the frame, it had huge lens flare artifact because I couldn't get it far enough out of frame to still have a good framing. To make matters worse it left giant diffraction spikes and some reflection artifacts in the broadband subs. Surprisingly, the H-alpha was all but free of this.

I must have reprocessed this at least half a dozen times trying to find the a way to show the image I wanted. I didn't get there 100% but I got further than I thought I might. Unfortunately, just after I saved my final image, my entire computer locked up so I didn't get to save a PixInsight project with all my steps and so I'm doing this from memory and given how many variations I did, I'm hoping I got this right.

H:
dynamic crop
blurXterminator
noiseXterminator
starXterminator (extracting stars)
GHS (GH, linear, GH)

each R, G and B
dynamic crop
DBE

RGB:
channel combination
SPCC
burXterminator
starXterminator (extracting stars)
noiseXterminator
GHS (GH, kenaf, GH)
Used masks to convolve out RGB artifacts
LRGBCombination (adding in H)
Curves (desaturate reflection nebula)
LHE (4 scars, very ow %)
Curves (adjust 'a' to boost reds)
Curves (contrast, a series of small contrast adjustments)
MLT (mild sharpening)
pixel math in stars
sight color adjustment in Photoshop

H stars:
GHS (GH)

rgb stars
GHS (GH)
LRGBCombination in h stars

Shenandoah Astronomical Society
LGBTQIA+ Astrophotographers
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Cloudy Nights
NOVAC
Imaged with N.I.N.A.
N.I.N.A. Users

Awards
SRO Planewave CDK14

	Distinct awarded users	Total awarded images
Image of the day
Top picks
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	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
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Extremely wide field
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Noctilucent clouds
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	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	8722015
PixInsight job	EUYBWY6LC3A4H3CJN0CXHRT0CQSPY2KO
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	05h40m44s.715
RA (top/left)	05h39m12s.371
RA (top/right)	05h39m04s.734
RA (bottom/right)	05h42m17s.550
RA (bottom/left)	05h42m24s.622

Dec (center)	-02°24′56″.66
Dec (top/left)	-02°01′58″.32
Dec (top/right)	-02°45′48″.57
Dec (bottom/right)	-02°47′53″.14
Dec (bottom/left)	-02°04′04″.21

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