Equipment:

OTA: William Optics GT81 w/0.8x reducer (382mm fl at f/4.7)

Mount: Orion Sirius EQ-G (HEQ-5)

Guidescope: Orion 50mm guidescope

Guiding camera: Orion StarShoot Autoguider

Imaging camera: ZWO ASI1600MM-Cool

Software:

SGP

PHD2

CdC

PixInsight

Acquisition:

Location: Flower Mound, TX (Bortle 7)

Dates: 12/9/17, 12/10/17, 12/11/17, 12/13/17, 12/20/17, 1/12/18, 1/13/18, 1/14/18, 1/16/18, 1/30/18, 1/31/18, 2/4/18

Gain: 200 Offset: 50

Camera temp: -20C

SII: 179x300" Astrodon 3nm

Ha: 283x300" Astrodon 5nm

OIII: 119x600" Astrodon 3nm

Total integration time: 58hr 20min

64x darks per calibration (master from library)

32x flats per calibration

200x bias per calibration (master from library)

Processing steps for original revision:

Preprocessing:

Batch PreProcessing script to generate calibrated images

StarAlignment

LocalNormalization (except OIII)

ImageIntegration (Linear Fit rejection)

DrizzleIntegration

DynamicCrop

DBE

LinearFit to SII

Duplicated all three masters. One set used for tonemap creation, and one set used for a synthetic Lum.

Preparing masters for the tonemap (all processes applied to each master individually):

TGV and MMT noise reduction (via Jon Rista's method)

Histogram Transformation x2 (linear -> non-linear)

Created a starmask and removed stars via MMT and MorphologicalTransformation

Further eliminated stars by bringing into Photoshop and using "Dust & Scratches"

Tonemap processing:

SHO masters assigned to RGB channels respectively to create a color image

HistogramTransformation

About 5 different curves adjustments (a and b channels) using ColorMask Script to target individual colors and adjust them to an aesthetically pleasing composition

SCNR green

L Processing:

Created a synthetic luminance with PixelMath using the following formula: Ha*0.7 + Oiii*0.2 + Sii*0.1

Deconvolution

HistogramTransformation x2 (linear -> non-linear)

ExponentialTransformation to push nebulosity

LHE

MMT for slight sharpening

Combined the Luminance with the Tonemap using LRGBCombination

Post-combination adjustments:

HistogramTransformation

CurvesTransformation for slight contrast

SCNR green

MorphologicalTransformation for slight star size reduction

DarkStructureEnhance Script

ACDNR for slight noise reduction

CurvesTransformation for slight saturation

Resampled to 50% for web posting