2018-05-05: NGC4258 M106 from Buford Mountain

Post date: May 28, 2018 9:17:9 PM

NGC4258 (M106)

NGC4258 (M106) imaged February 18, March 3 and May 5, 2018 using a 150 mm aperture, 750 mm focal length telescope and QSI 683wsg8-3 camera with Astrodon Gen 2 L, R, G, B and 3 nm Ha filters. The exposure times were L – 100 min, Ha – 210 min, R – 80 min, G – 90 min, B – 80 min min, for a total exposure time of 9 hours 20 min. The images were taken at Buford Mountain Conservation Area.

This is the full image at half resolution.

This is a full resolution 2x crop of the central region:

Processing in PixInsight 1.8

• • Calibration

  • StarAlign

  • Integration

  • DynamicCrop

  • Liminance

DynamicBackgroundExtraction

Deconvoluation

MultiScaleMedianTransformation

LocalHistogramEqualization

MorphologicalTransformation to reduce star size

Gamma curve adjustment

MultiScaleMedianTransformation

• • R, G, B

LinearFit

PhotmetricColorCalibration

SCNR

Background desaturation

Star Saturation

ACDNR

• • Ha

Deconvolution

LocalHistogramEqualization

Gamma curve adjustment

MultiScaleMedianTransformation

• • LHa

Added Ha: 0.75*M*L+0.25*M*Ha with a strong L Luminosity mask in place to protect background

• • LHaRGB

• Pixel Math blending:

P001.expression = "(1-wHa*$M)*$T[0]+1.4*wHa*$M*Ha_Final";

P001.expression1 = "(1-wG*$M)*$T[1]+wG*$M*Ha_Final";

P001.expression2 = "(1-wHb*$M)*$T[2]+1.2*wHb*$M*Ha_Final";

• • ACNR