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Getting plate-solving status, please wait...
Lobster Claw (modified SHO), 


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Lobster Claw (modified SHO)

Getting plate-solving status, please wait...
Lobster Claw (modified SHO), 


Powered byPixInsight

Lobster Claw (modified SHO)

Acquisition details

Oct. 5, 2021 ·  Oct. 6, 2021 ·  Oct. 7, 2021
Astrodon H-alpha 3nm: 52×360(5h 12′) (gain: 56.00) -5°C bin 1×1
Astrodon OIII 3nm: 24×360(2h 24′) (gain: 56.00) -5°C bin 1×1
Astrodon SII 3nm: 46×360(4h 36′) (gain: 56.00) -5°C bin 1×1
12h 12′
Flat darks:
Avg. Moon age:
9.88 days
Avg. Moon phase:
Bortle Dark-Sky Scale:

RA center: 23h14m37s.70

DEC center: +60°1255.6

Pixel scale: 1.115 arcsec/pixel

Orientation: -90.289 degrees

Field radius: 1.163 degrees

WCS transformation: thin plate spline

More info:Open 

Resolution: 6252x4176

File size: 650.8 KB

Locations: Maurertown, Maurertown, VA, United States

Data source: Backyard


A rare image form home this year. The clouds have been all but interminable this summer and fall and the clear nights were either marred by the smoke out west, 90+% humidity or the moon. But, beggars can't be choosers when it comes to clear skies at home.

This data was acquired between 25 Sep 2021 and 21 Oct 2021. The dates listed above are just in the middle of the range.  I ended up not using a good chunk of the data I collected thanks to sky issues (alas, Normalize Scale Gradient is a harsh mistress and said a good chunk of the dat was not up to snuff thanks to the aforementioned obstacles) and it it tedious to figure out exactly how many frames from each day got used. Despite the loss of data I'm fairly happy with this. 

Here's the processing:

S H and O masters:
histogram transformation
tgv denoise

channel combination (SHO)
histogram transformation
MLT sharpening
curves contrast and hue
pixel math in stars

channel combination in the stars extracted by starxterminator
histogram transformation

I tried to keep a light touch on things like LHE and sharpening as they easily made a very chaotic nebula look over processed. Hopefully I stayed on the good side of that line. I did push the colors around with the hue control in curves as I wasn't especially happy with the look of the straight SHO combine