NGC 7000 - North American Nebula

www.astrobin.com/9292ng/

 

Integration: 35 hrs

Telescope: Esprit 100

Camera: ASI183MM

Mount: CEM60

Filters: Astrodon 3nm Ha & OIII

Subs: Ha 107x600", OIII 103x600"

Gain/Temp: 111/-15

Pixel Scale: 0.89 arcsec/pixel

 

Preprocessing: Master dark-flat to calibrate the flats. Master dark and master flat to calibrate the lights. CosmeticCorrection. Nearest Neighbor star alignment was used because MUREDenoise would be applied after integration. ESD integration.

 

Postprocessing:

- MUREDenoise

- STF to HT nonlinear stretch

- Starnet++ (and CloneStamp to fix artifacts left over from the largest stars)

- Local Histogram Equalization on starless and pre-Starnet versions

- Curves Transformation on OIII (starless and pre-Starnet versions) to match OIII's dark nebula to HA and raise OIII midtones

- PixelMath color combination of the starless versions

Red: HA

Green: OIII*.4 + HA*.6

Blue: OIII

- PixelMath luminance combination using the pre-Starnet versions

max(HA * 1), (OIII * .25)

- LRGBCombination

- CurvesTransformation to raise the midtones (star mask for the largest stars)

- DarkStructureEnhance

- LocalHistogramEqualization (star mask for the largest stars)

Done