B110 Region

B110 RegionClick image for full size version (LARGE FILE)

July 12, 2021

This image shows the B110 region in Scutum, a small constellation overflowing with dark nebulae. These dark patches of dust obscure the starlight behind them, making interesting dark shapes in the rich star fields of the Milky Way. I prepared an annotated image that identifies some of the many catalogued dust clouds in this photo. 

Tekkies:
Acquisition, focusing, and control of Paramount MX mount with N.I.N.A., TheSkyX and PHD2. Focus with Optec DirectSync motor and controller. Equipment control with PrimaLuce Labs Eagle 3 Pro computer. All pre-processing and processing in PixInsight. Acquired from my SkyShed in Guelph. Average transparency and seeing. Data acquired May 10-13, 2021 in a nearly moonless sky.

Luminance: Sky-Watcher Esprit 150 f/7 refractor and QHY600M camera with Optolong UV/IR filter
Chrominance: Takahashi FSQ-106 ED IV @ f/5 and QHY367C Pro one-shot colour camera with Optolong UV/IR filter

48x5m Lum = 4hr00m
104x5m chrominance = 8hr40m
Total: 12hr40m
 
Image scale 0.72 arcsec per pixel (based on Luminance)
 

Data Reduction and Initial Processing
Preprocessing: The WeightedBatchPreProcessing script was used to create a Luminance master frame from the mono camera and registered frames from the one-shot colour camera. The OSC subs were integrated with DrizzleIntegration (CFA Drizzle x2) and the resulting RGB master was registered to the Luminance master using StarAlignment.

Gradient Removal: DBE was applied to both masters using Subtraction.

Colour
Colour Balancing:  Colour was balanced with PhotometricColorCalibration.

Linear Noise Reduction: MultiscaleLinearTransform was used to reduce noise in the background areas, using an internal mask to protect bright structures. Layer settings for threshold and strength: Layer 1: 5.0 0.85, 2 iterations; Layer 2: 3.5, 0.75, 2 iterations.

Stretching:  HistogramTransformation was applied to make a pleasing, bright image, with background set to an intensity of approximately 0.10.

Lightness
Linear Noise Reduction:  MultiscaleLinearTransform was used to reduce noise in the background areas, using an internal mask to protect bright stars. Layer settings for threshold and strength: Layer 1: 3.0 0.85, 1 iterations; Layer 2: 2.0, 0.75, 2 iterations.

Stretching:  HistogramTransformation was applied to make a pleasing, bright image, with background set to an intensity of approximately 0.10.

Combining Lightness and Colour Images
LRGB Combination: The lightness image was applied to the RGB image using LRGBCombination with default settings.

Additional Processing

Nonlinear Noise Reduction: TGVDenoise was used in L*a*b* mode to reduce noise with a mask used to target the background areas and protect the stars and galaxy (max. 1,000 iterations and convergence selected for both lightness and chrominance). 

Final Steps: Background, galaxy and star brightness, contrast, and colour saturation were adjusted in several iterations using CurvesTransformation with masks as required. ICCProfileTransformation (sRGB IEC61966-2.1; Relative Colorimetric with black point compensation) was applied prior to saving in jpg format.