The Pillars of Creation: My image compared to Hubble's

Image from external-preview.redd.it and submitted by azzkicker7283
image showing The Pillars of Creation: My image compared to Hubble's

azzkicker7283 on May 17th, 2020 at 00:00 UTC »

Since I know at least one person will ask: I use an equatorial mount that tracks the stars as they move across the sky. This way I can do long exposures without having the star trailing. My image also isn't one single long exposure, but a stack of 180 6 minute long exposures totalling ~18 hours. I also use narrowband filters to cut through the light pollution, which means my image (and Hubble's since it's the same filters) are both false color.

I've been planning on shooting M16 in SHO for over a year now. I decided to wait until I could acquire a Sii filter, which wasn't until early April. I also wanted to total 20+ hours on this before moving home and graduating college, which I got fairly close to thanks to online classes and no sleep schedule. In order to maximize the amount of time I could get on it, I began shooting from once it hit 20 degrees altitude until the end of nautical dark (average of 2.5 hours per night). Also here are the full-size versions of my image as well as Hubble's. Captured on the nights of March 31, and April 2, 5, 15, 20, 21, and 24 from my apartment roof in Athens, GA (Bortle 7 zone).

If you want to see more of my photos check out my:

Instagram | Flickr | Astrobin

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 for guiding

Moonlite Autofocuser

Acquisition: 18 hours 12 minutes (Camera at Unity Gain, -20°C)

Sii- 61x360"

Ha- 60x360"

Oiii- 61x360"

Darks- 30

Flats- 30 per filter

Capture Software:

Captured using N.I.N.A., EQMod mount control, and PHD2 for guiding and dithering.

PixInsight Processing:

Blink

BatchPreProcessing

StarAlignment

ImageIntegration

DrizzleIntrgration (2X, VarK 1.5)

DynamicCrop

AutomaticBackgroundExtraction (function degree: 1, division mode)

Duplicated Ha to act as Luminance

Luminance Processing:

Deconvolution

PixelMath to add back in pre-decon stars

Decon+star restoration method similar to the one outlined in OkeWoke's tutorial

TGV/MMT Noise reduction

Jon Rista noise reduction tutorial

ArcsinhStretch

HistogramTransformation

Individual Sii, Ha, and Oiii channel Processing:

ChannelCombination (SHO mapped to RGB, respectively)

SHO Processing:

Unlinked STF applied via HistogramTransformation

LRGBCombination with nonlinear Lum (chrominance noise reduction enabled)

Invert > SCNR > Invert (repeated twice)

This removes a magenta cast common on Hubble palette images

SCNR

Removes some of the overwhelming green. Ha has the strongest signal and was initially mapped to the green channel.

Several CurveTransformations for lightness, saturation and color adjustments (mostly red and green channels)

Star mask

HDRMultiscaleTransform

Helps bring out the pillars in the brighter core region

More curves for color tweaking nebula and stars

Invert > SCNR > Invert with a star mask

This was to reduce the magenta stars common in Hubble palette images. I opted to preserve some of the magenta stars in the core to better match the look of the 2014 HST image of the pillars

HistogramTransformation to slightly boost red channel

DarkStructureEnchance

Invert > SCNR > Invert again to tweak overall magenta color

ACDNR

Nonlinear noise reduction

LocalHistogramTransformation

Boosts contrast, especially in the core region

More curves with range mask

tweaking core region colors

MorphologicalTransformation to reduce star sizes

More curves for more color tweaks

ACDNR

Final noise reduction tweaks

One last curve transformation to tweak green channel

I ended up doing a lot of my nonlinear processing with the green channel adjusted via STF, and didn't realize until the very end. Forgot to save the original STF process, so I tried to replicate it as best I could using curves

Resample to 85%

Annotation

DanielJStein on May 17th, 2020 at 00:04 UTC »

Stunning dude. The colors look great and the detail is exceptional!

RSwordsman on May 17th, 2020 at 00:07 UTC »

It was seeing the Pillars of Creation as a kindergartener that hooked me on space for life. Your picture is better than I thought would ever be possible from an earth-based telescope.