This is a High Dynamic Range composition, consisting of twenty-five 5-minute exposures and twenty-five 30-second exposures each using narrowband SHO filters (Sulfur II=red, Hydrogen I=green, and Oxygen III=blue). The exposures were captured over a three night period, as I only have about two hours of this object being visible amongst the trees in my neighborhood. My goal was to take the time to carefully process each individual elements contribution to the overall image, attempting to divulge as much detail from each channel as possible before combining the master frames.

I was lucky enough to catch the core area during a time of really good seeing for my area (about 1am after everything had mostly thermally equalized and the sky happened to be rock steady), I took a total of fifty 30-second exposures using each filter, I then used Blink/SubframesSelector to choose only the 25 frames having the lowest FWHM from each of these sets for the final core area masters.

Each individual set of filtered files (for outer area and core area) was processed as follows: Calibration,Alignment (to the lowest FWHM file of the bunch),Inspection,LocalNormalization (using a reference of six carefully chosen frames that were integrated,noise reduced, and DBE'd),Integration, MureDenoise.

I then used HDRComposition to combine each of the above integrated masters into SHO masters, and then processed each of these masters as follows: LinearFit,Deconvolution (with appropriate LumMask),StarMask (to create several various StarMasks for each master),MaskedStretch, MLT/MT/Starnet (all with appropriate masking),HDRMT and LHE (with appropriate masking), custom CurvesTransformation, MLT (noise reduction).

Then I used LRGBCombination using the now processed SHO masters, multiple iterations of CurvesTransformation, mild UnsharpMask (with appropriate LumMask), ColorSaturation, and HistogramTransformation for final adjustments of each color channel.

A bit of interesting info regarding Messier 42:

In the early 90's, while at Texas Star Party, I had a research astronomer describe the Orion Nebula to me in the following way...he said, "Imagine a large flesh-eating blister sitting atop your leg. Then one day, while you are looking at it really close, it POPS!" The model that modern astrophysicists use to describe the morphology of this area of sky is indeed called the "blister" model. The "blister" of the Orion Nebula is caused by the birth of several successive generations of hot, massive stars located near the dark core of the object. This area of rapid starbirth happens to be occuring near the outer edge of a gigantic molecular cloud of gas and dust (known as the Orion Molecular Cloud)...this is occuring along the edge that is conveniently facing Earth! One such group of young stars, probably forming about 4 million years ago, is known as the "trapezium". These four stars can be glimpsed in this image if one zooms in near the center. The brightest of the trapezium stars, known as Theta 1C Orionis, has a surface temperature of >70,000 F (our Sun sits at a comfy 10,000 F). This combined with its estimated mass of 40 times that of the Sun, makes Theta 1C some 200,000 times brighter than our very own star. And considering that the collective stellar wind being released by the trapezium stars is along the lines of 5 million mph, this makes for a very volatile area of space! The intense UV radaition and strong stellar winds from the trapezium stars are carving out "streams" of ionized gas as it bursts through the facing edge of the dark cloud in our direction. This is what is thought to be responsible for the wonderful colorful streamers and filaments that we witness here as the Orion Nebula.

The "flesh-eating" part of the nebula is a dense cluster of extremely hot newborn stars located behind the formerly mentioned "trapezium" stars near the dark core of the nebula. Due to the dense clouds of interstellar dust and the high levels of ionization, these more recently formed clusters of stars can not be seen in the visible part of the spectrum. Infrared imaging, however, shows them clearly. As succesive generations of such stars repeatedly gather dust and gas from the OMC, and then within several million years die in violent supernova explosions, the core of the Orion Nebula is quite literally "chewing" its way deeper into the Orion Molecular Cloud!