Crescent Nebula Processing Sequence (KuriousGeorge)

Crescent Nebula Processing Sequence

Lots of Crescent Nebula postings and all very different. (-:

IMHO, this object is particulary interesting to process because the wideband RGB, which is rich in Ha, shows very little of the traditional SII and OIII mapped narrowband colors.

Of course levels and hues make a big artistic difference. In this case, I started with level-normalized channels and tweaked lightness a bit when one looked a bit overpowering...

Filter Color Hue Lightness

Ha Red 360 -60

OIII Blue 200 -50

SII Green 120 -50

I started with an RGB channel having only PI PCC and a Masked Stretch applied. No deconvolution or sharpening.

I then overlayed Ha as a lighten layer and color balanced space using PS Color Balance Shadows with several 32x32 sample points.

I then followed a similar process with a starless SII and OIII lighten overlay (to help preserve star color) with an occasional green reduction.

Finally I overlayed the RGB channel again at the end to help restore any lost star color.

Other than tweaking channel lightness, no other color tweaks were applied. Very minimal processing.

Final result may be seen here...

Crescent Nebula and Milky Way Stars

Please note: The following tables are updated every 24 hours.

Distribution of astrophotographers

This table shows the number of distinct astrophotographers who have been assigned and IOTD/TP award compared to the total number of images awarded.
	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
Noctilucent clouds
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.	...
Views by Submitters (available since September 19th, 2023) Every image is assigned to 50% of available Submitters. In the event that at least 80% of them don't view the image before its time in the IOTD/TP process expires, it's assigned to the other 50% of Submitters and the process begins anew.
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Promotions by Reviewers When 3 distinct Reviewers promote the image, it moves on to the next stage of the process: evaluation for IOTD status.
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Status	Basic failed
Started	...
Astrometry.net job	3635265
PixInsight job	n/a
PixInsight queue size	n/a
PixInsight stage	n/a

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