Horsehead Nebula (starless) imaged in Hydrogen-alpha (Andrew Klinger)

Horsehead Nebula (starless) imaged in Hydrogen-alpha

I revisited my 2017 Horsehead Nebula data to experiment with new techniques on the Hydrogen-alpha channel. Removing the stars with new software "StarNet" I was able to showcase just how densely packed this area of sky is with dust.

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

StarNet

Acquisition:

Location: Flower Mound, TX (Bortle 7)

Dates: 10/23/17, 11/24/17, 12/8/17

Gain: 200 Offset: 50 for Ha

Gain: 76 Offset: 15 for RGB

Camera temp: -20C

Ha: 164x300" Astrodon 5nm

Total integration time: 13hr 40min

64x darks per calibration (master from library)

30x flats per calibration

200x bias per calibration (master from library)

Preprocessing:

Batch PreProcessing script to generate calibrated images

StarAlignment to register all frames to the reference

LocalNormalization of all registered frames

ImageIntegration

DrizzleIntegration

DynamicCrop

DBE

Ha Processing:

Deconvolution

TGV Noise Reduction

ArcsinhStretch

HistogramTransformation

Used external software "StarNet" to remove stars

PIxelMath expression "1-(1-$T)*(1-$T)" to push fainter nebulosity

LocalHistogramTransformation

MultiscaleLinearTransform sharpening

Resampled to 30% for web posting

Final
Original
B

B

Description: With stars

Uploaded: ...

Narrowband imaging

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Status	Basic failed
Started	...
Astrometry.net job	2639316
PixInsight job	n/a
PixInsight queue size	n/a
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