Cygnus constellation

Tags: 2019-07-24 cygnus ngc7000 widefield nebula dso astrophotography ccd narrowband bicolor
Acquisition date(s):
2019-07-24, 2019-07-20
Description
During annual gathering with local amateur astronomers, I borrowed this Samyang lens (unfortunately, it has it's issues as seen in bottom right) as I wanted to do this widefield of whole cygnus area for a while. It still doesnt get completely dark and on top of that, almost full moon was shining, but the outcome is quite pleasing nevertheless, even though the stars do not look that great.

Equipment/Acquisition Details:

Imaging Scope: Samyang 14mm F2.8 (shot at F2.8)

Imaging Camera: Starlight Xpress Trius-SX694 Mono CCD

Filter Wheel: Gerd Neumann filter drawer

Filters: 1.25" mounted Astrodon Ha 3nm and Astrodon OIII 3nm

Mount: Star Adventurer (unguided)

Accessories/Software: Sequence Generator Pro, PixInsight

Integration Details: 20x300s Ha (1x1bin), 24x300s OIII (1x1bin) TOTAL: 3.6 hours.

Dates: 2019-07-20

Darks: 30

Flats: 30

Bias: 200

Processing details:

Pre-processing

SFS process to calculate weigh keyword
Crop

Ha, OIII

DBE
MMT using 7 layers with adaptive setting
HistogramTransformation- stretch to taste
MLT to increase sharpnes using lum mask
Adam Block's approach towards removing stars- creating star ring mask using bloatedStarMask-starmask, then making a starless image, and replacing the ring space with starless image pixels.

Bicolor

Removed stars in OIII and Ha with StarNet++
PixelMath to combine

Red: iif(ha > .15, ha, (ha*.8)+(oiii*.2))
Green: iif(ha > 0.5, 1-(1-oiii)*(1-(ha-0.5)), oiii *(ha+0.5))
Blue: iif(oiii > .1, oiii, (ha*.3)+(oiii*.2))

CurvesTransformation to increase contrast, saturation and color tweaks
MMT using 7 layers and adaptive setting
LRGBCombination with Ha as Lum
Invert->SCNR green->invert to reduce unwanted magenta in background
SCNR
ICCProfileTransformation assign sRGB profile
Signature script