The Antennae Galaxies (NGC 4038/4039) are a pair of colliding galaxies about 65 million ly away. The collision over the last few hundred million years has resulted in streams of ejected stars, forming the ‘antennae’. Despite having guide camera issues for the first hour of the night, and horrific seeing/guiding error/HFR values, this somehow turned out decent. I’ve also made an annotated version which highlights background galaxies in the uncropped FOV.

Captured on April 20th, 2023 from the Deerlick Astronomy Village (Bortle 3)

Places where I host my other images:

Instagram | Flickr

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Equipment:

• TPO 6" F/4 Imaging Newtonian

• Orion Sirius EQ-G

• ZWO ASI1600MM-Pro

• Skywatcher Quattro Coma Corrector

• ZWO EFW 8x1.25"/31mm

• Astronomik LRGB+CLS Filters- 31mm

• Astrodon 31mm Ha 5nm, Oiii 3nm, Sii 5nm

• Agena 50mm Deluxe Straight-Through Guide Scope

• ZWO ASI-120mc 290mc for guiding

• Moonlite Autofocuser

Acquisition: 3 hours 52 minutes (Camera at half Unity Gain, -15°C)

• L- 55x120"

• R - 21x120"

• G - 21x120"

• B - 19x120"

• Darks- 30

• Flats- 30 per filter

Capture Software:

• Captured using N.I.N.A. and PHD2 for guiding and dithering.

PixInsight Processing

• BatchPreProcessing

• SubframeSelector

• StarAlignment

• Blink

• ImageIntegration

• DrizzleIntegration (2x, Var β=1.5)

Luminance Linear:

• DynamicCrop

• DynamicBackgroundExtraction

• BlurXTerminator (i caved)

• NoiseXterminator

• ArcsinhStretch+HistogramTransformation to bring nonlinear

RGB Linear:

• DynamicCrop

• DynamicBackgroundExtraction

• ChannelCombination

• SpectrophotometricColorCalibration

• HSV Repair

• AcrsinhStretch + HistogramTransformation to stretch nonlinear

Nonlinear:

• added stretched luminance to stretched RGB via LRGBCombination

• DeepSNR

• shitloads of CurveTransformations to adjust hue, lightness, saturation, etc. (some with star masks)

• more curves

• LocalHistogramTransformation

Two round of this: one at kernel radius 16 for the finer ‘feathery’ details and one at 200 something for larger structures

• SCNR green

• CloneStamp to remove one weirdly saturated Ha region (it looked bad)

• even more curves

• NoiseX

• UnsharpMask

• curves!

• BlurXTerminator (star reduction only)

• MLT for chrominance noise reduction

• guess what more curves

• final curves

• Resample to 70%

• DynamicCrop again

• annotation