lefty7283

Sh2-157 - The Lobster Claw Nebula

https://lemmy.world/post/38383160

Nov 5 at 8:55pmWeb
Show threadlefty7283Nov 5

It actually looks like it’s namesake!

This is a combo of SHO hubble palette + true color RGB for the stars. Captured in October 2025 from a Bortle 9 zone.

Places where I host my other images:

Flickr | Pixelfed

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, Sii 5nm

  • Agena 50mm Deluxe Straight-Through Guide Scope

  • ZWO ASI-290mc for guiding

  • Moonlite Autofocuser

Acquisition: 49 hours 56 minutes (Camera at -15°C)

  • Ha - 63x600"

  • Oiii - 122x600"

  • Sii - 102x600"

  • R - 63x60"

  • G - 63x60"

  • B - 63x60"

  • Darks- 30

  • Flats- 30 per filter

Capture Software:

  • Captured using N.I.N.A. and PHD2 for guiding and dithering.

PixInsight Preprocessing:

  • BatchPreProcessing

  • StarAlignment

  • Blink

  • ImageIntegration per channel

  • DrizzleIntegration (2x, Var β=1.5)

  • Dynamic Crop

Narrowband linear:

  • MultiscaleGradientCorrection using MARS project data (had to do good ol fashioned DBE for the Sii channel)

  • BlurXterminator

  • StarXterminator to completely remove stars

  • STF applied via HistogramTransformation to stretch nonlinear

RGB Linear:

Channelcombination to make color image from RGB stacks

  • MultiscaleGradientCorrection (this is some seriously impressive shit!)

  • SpectrophotometricColorCalibration

  • BlurX (correct only mode)

  • HSV Repair

  • StarX to extract a stars only image

  • ArcsinhStretch + HistogramTransformation to stretch nonlinear

  • Slight curves saturation boost

Nonlinear processing:

  • Pixelmath to combine stretched narrowband images into color image (SHO/Hubble palette)

  • SCNR > Invert > SCNR > Invert to remove some greens and magentas

  • DeepSNR

  • Shitloads of curve transformations to adjust luminance, contrast, saturation, etc

  • HistogramTransformation to further stretch the red channel a little

  • more curves

  • NoiseX for some small scale chrominance noise reduction

  • Pixelmath to add in the stretched RGB stars only image from earlier

    This basically re-linearizes the two images, adds them together, and then stretches them back to before. More info on it here)

    mtf(.005,

    mtf(.995,Stars)+

    mtf(.995,Starless))

  • Slight SCNR

  • Resample to 65%

  • Annotation

Show threadshalafiNov 5
A lobster claw is not what I’m seeing here.