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
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
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
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