• @lefty7283OPMEnglish
    2•11 months ago

    It’s just a big ball of stars. I decided to try out a broadband target while waiting for some others to come into my view. Thanks to my wonderful horizons and the fact that this this is at dec +30 I only had a half hour window per night to shoot it. Still pleased with the results, especially with my light pollution. Captured over 4 nights from December 14-19, 2023 from a Bortle 9 zone.

    Places where I host my other images:

    Flickr | Instagram

    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-120mc for guiding

    • Moonlite Autofocuser

    Acquisition: 2 hours 32 minutes (Camera at unity gain, -15°C)

    • Lum - 77x60"

    • Red - 27x60"

    • Green - 24x60"

    • Blue - 24x60"

    • Darks- 30

    • Flats- 30 per filter

    Capture Software:

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

    PixInsight processing:

    Preprocessing

    • BatchPreProcessing

    • StarAlignment

    • Blink

    • ImageIntegration per channel per panel

    • DrizzleIntegration (2x, Var β=1.5) per panel per channel

    Narrowband Linear:

    • DynamicBackground Extraction

    duplicated each image and removed stars via StarXterminator. Ran DBE with a shitload of points to generate background model. model subtracted from original pic using the following PixelMath (math courtesy of /u/jimmythechicken1)

    $T * med(model) / model

    • BlurXterminator for star correction

    • ArcsinhStretch + HistogramTransformation to bring nonlinear

    RGB linear

    • DynamicBackground extraction as above

    • ChannelCombination to combine R G and B stacks into color image

    • SpectroPhotometricColorCalibration

    • BlurXterminator star correction

    • HSV Repair

    • ArcsinhStretch + HT to bring nonlinear

    Nonlinear:

    • LRGBCombination with stretched RGB pic and stretched L pic as luminance

    • shitloads of CurveTransformations to adjust hue, lightness, saturation, etc. (some with lum masks)

    • DeepSNR

    • Slight SCNR Green

    • More Curves

    • Resample to 70%

    • DynamicCrop again

    • Annotation