Another rudiment of astro imaging is M42, the Great Nebula — a must for an aspiring newbie like me. The rewards are great for a successful image, yet there is challenge in taming the wide dynamic range of the nebula. It was a good test of a basic workflow that I am trying to put together.

I returned to Colorado for the holidays to visit family and see a friend graduate, and fortunately it was near dark time! This is the result of my first evening of imaging, which, unfortunately, may be the last of this cycle as the weather reports aren't promising here on the Palmer Divide north of Colorado Springs.

Another crummy night for seeing here in the lee of the Rockies. Average seeing here is ~2.5", with anything below 2" exceptional. Tonight it was 4" or worse. I wanted to check things out after being away for a bit and figured the data would give me something to experiment with. I was anxious to see how the AP155 would perform on this beautiful target.

This is a simple RGB combination with fifty 60-sec exposures in each filter.

After channel combination, I applied several new Pixinsight tools in addition to the standards. SPCC for color calibration, Russell Croman's Blur Xterminator and Noise Xterminator (with a mask to avoid making the Trapezium look like worms), followed by several applications of @David Payne  and @Mike Cranfield 's brilliant Generalized Hyperbolic stretch (Hyperbolic + Linear to raise Black Level + Hyperbolic to bring out some fainter details.) SCNR got rid of the green chrominance noise, followed by PI's HDRMT using the a Trous wavelet transform and the gaussian scaling function (thanks @Adam Block) with a lightness mask. One more bit of GHS to make the Trapezium a bit apparent and I think I am ready to show it.

I was amazed at how well Blur Xterminator dealt with the bloated star images. It would a taken me a week of noodling around with deconvolution and I don't think I would have gotten as close at BX did in the first application. (I did try several runs with BX..)

When I was an undergraduate at the University of Arizona in 1973, I worked in the lab in Bart Bok's Astronomy 1A class. To reward us for our work, Bok took all of the lab assistants to Kitt Peak.  There I got to view M42 through UA's 2.4m (now the Bok) reflector! M42 was burned into my head and it was fluorescent green! I am hoping to take a few good OIII frames i captured and use them to add a bit of what I saw using some of the dynamic narrowband combination techniques from The Coldest Night website. Wish me luck.

Of course, your constructive comments will be welcomed!