• lefty7283@lemmy.worldOPMEnglish
    3·
    4 months ago

    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