SH2-275 The Rosette Nebula (Kevan Noble)

SH2-275 The Rosette Nebula

Not having captured anything since August due to poor weather, I have spent time improving my post processing knowledge in Pixinsight and Photoshop. This reprocess (although first time on Astrobin) of The Rosette Nebula incorporates a new technique (for me) called Luminance Masking. The creation of Light, Dark and Mid Luminance masks of differing levels allow selective adjustment layers to selectively pull out the darker areas without overexposing the rest. It’s what we try to achieve anyway but this technique allows much greater control.

Additionally I wrote my first Action Set in Photoshop to recreate these masks, plus Curve and Vibrance adjustment layers from each mask with just one click. As they say - Every cloud has a silver lining! We have certainly had plenty of cloud for sure.

SH2-275, The Rosette Nebula, lies about 5,200 light-years from Earth in the constellation Monoceros the Unicorn, and is about 130 light-years across. The Nebula, contains enough gas and dust to make about 10,000 stars like our Sun. In the centre of the nebula is a cluster of hot, bright young stars. These are warming up the surrounding gas and dust, making it appear bluer. The small, bright white regions are cocoons of dust in which huge stars are currently being born. These “protostars”, each one of which will probably become a star up to ten times more massive than the Sun, are heating up the surrounding gas and dust and making it glow brighter. Just as the centre of the nebula contains bright young stars, in a few tens or hundreds of millions of years these stars will have died, but the protostars will have evolved into fully-fledged stars in their own right. In this way, the star formation will move outwards through the nebula.

Shot January 28 and 31 2022. Seeing wasn’t great with a strong jet stream and clouds on the 31st, so shot short exposures to dance between the clouds dumping the worst frames.
Sii 300s x 15 plus 60s x 20
Ha 300s x 17 plus 60s x 20
Oiii 300s x 15 plus 60s x 20
RGB Stars 20+20+20 x 60s
5.9 hours total
Astromiks 50mm SHO 6nm and RGB Filters
30 x Darks, Flats (for each narrowband filter) and Bias
ZWO ASI6200MM Pro at 100 gain, -5C
ZWO 7x2" EFW
ZWO EAF
Williams Optics GT81 IV
WO 6A III Field Flattener 0.8
HEQ5 Pro Rowan
ASIAIR Pro
Astro Pixel Processor
Pixinsight
Photoshop 2022

	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
Artificial satellite

	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

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.
Promotions by Submitters When 3 distinct Submitters promote the image, it moves on to the next stage of the process: evaluation for Top Pick status. This requirement, in addition to anonymization of images and distribution to only a subset of them, prevents biases and ensures that the best images are selected.
Promotions by Reviewers When 3 distinct Reviewers promote the image, it moves on to the next stage of the process: evaluation for IOTD status.
Early dismissal Staff members have a lot of images to inspect on a daily basis, and they can dismiss images if they believe they don't meet the requirements for IOTD/TP selection. If an image is dismissed 5 times, it's removed from the process. This streamlines the process and ensures that any bias present in promotions could be overruled by other staff members.

Status	Advanced success
Started	...
PixInsight job	QLZ9CFLBSBIN9B16ADQ1H4YGC0ARZDUF
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	06h32m30s.60
RA (top/left)	06h36m04s.95
RA (top/right)	06h35m51s.36
RA (bottom/right)	06h28m57s.70
RA (bottom/left)	06h29m11s.24

Dec (center)	+05°14′44″.7
Dec (top/left)	+03°53′41″.10
Dec (top/right)	+06°37′19″.5
Dec (bottom/right)	+06°35′21″.3
Dec (bottom/left)	+03°51′27″.2

AstroBin

AstroBin

Image Index:

Contribution Index (beta):