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  • It may not be as big or well known as the other well known cluster in Hercules (M13), but it sure looks nice. Captured over 4 nights in July/August 2024 from a Bortle 9 zone

    Places where I host my other images:

    Instagram | Flickr

    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: 6 hours 55 minutes (Camera at half Unity Gain, -15°C)

    • Lum - 209x60"
    • Red - 78x60"
    • Green - 62x60"
    • Blue - 66x60"
    • Flats- 30 per filter
    • 24 JimmyFlats per filter

    Capture Software:

    PixInsight Processing:

    • BatchPreProcessing (with premade JimmyFlats)
    • StarAlignment
    • Blink
    • ImageIntegration
    • DrizzleIntegration (2x, Var β=1.5)
    • DynamicCrop
    • DynamicBackgroundExtraction

    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

    Luminance:

    • BlurXTerminator (correct only mode)
    • ArcsinhStretch + histogramtransformation to bring nonlinear

    RGB:

    • ChannelCombinaiton to combine monochrome R, G, B stacks into color image
    • BlurXTerminator (correct only mode)
    • SpectroPhotometricColorCalibration
    • HSV Repair
    • ArcsinhStretch + histogramtransformation to bring nonlinear
    • Curves to saturate it a little
    • MLT for large scale chrominance noise reduction

    Nonlinear:

    • LRGBCombination with stretched L as luminance
    • DeepSNR Noise reduction
    • Several CurveTransformations to adjust lightness, contrast, colors, saturation, etc.
    • Invert > SCNR > invert > SCNR to remove some greens and magentas
    • More curves
    • A little bit of noiseXterminator
    • DynamicCrop in on the clustert
    • Resample to 75%
    • Annotation