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© 2016 Kwang Lee

M42, the Orion Nebula, and NGC 1977, the Running Man nebula

I had to devote several nights to getting the exposures to make this image. This was shot on the nights of Nov 24, 25, 30, then Dec 14 and 15. I used 31 x 15 min exposures, 46 x 5 min exposures, 35 x 2 min exposures, 35 x 15 seconds, and 35 x 5 seconds. That's about 13 hours of exposure. I actually shot about 17 hours of total exposure, but I only used the best 80% of the shots to process the image.

Scope: Takahashi TSA102S w/Televue .8x focal reducer/flattener.

Mount: Used AP1200.

Misc: Guided w/Orion 50mm guidescope and QHY5II-L autoguider.

It's kind of a mandatory shot for any astrophotographer, but I wanted to do it because I knew I would get something worthwhile as it's so bright.

There are issues with the image. The darker dust structures around the edges of the brightest parts are noisy. I got those structures from those longer 15 min subexposures, but I think I need like 3-4 times the number of 15 minute exposure which means another 3+ nights of imaging this object. Getting extra 15 minute shots would increase the signal-to-noise ratio which translates into less noise and more structure.

I was sorta lazy with using layer masks (a technique in Photoshop) and some of the stars are not the right brightness (too large) relative to other stars.

Sharpness is an issue. Overall, I think the image is a little blurry - except near the core of the Orion nebula where the Trapezium is located (the tiny grouping of 4 stars near the center). And that Trapezium is weirdly detailed with respect to everything else.

The overall color is little garish to me. I know this object gets overly saturated by most people and I ended up doing the same thing.

Also, there is some curvature in all the corners, but most obviously in the upper right and left respectively. I've known about this for awhile, but I haven't bothered to address it. *I think* it's focuser tilt as the curvature seems to be different depending on the orientation of the camera. I also picked up some spacers to place between the flattener and the camera. If you look closely to the bottom edge, just to the right of the center you can see some artifacts from the constant parade of satellites I had to deal with. Actually the satellites aren't moving, there's a bunch of geostationary satellites that happen to be located in M42
Kwang Lee

© 2015 Klaus Brasch

IC 443 (aka the Jellyfish Nebula or Sharpless 248)

December 15, 2015

A mosaic of about a half dozen exposures taken with my TMB-130 apo with the Canon 6Dat ISO 3200-6400 and IDAS LPS v3 filter. Cumulative exposure about 30 minutes."

IC 443 (also known as the Jellyfish Nebula and Sharpless 248 (Sh2-248)) is a Galactic supernova remnant (SNR) in the constellation Gemini. On the plan of the sky, it is located near the star Eta Geminorum. Its distance is roughly 5,000 light years from Earth.

IC 443 may be the remains of a supernova that occurred 3,000 - 30,000 years ago. The same supernova event likely created the neutron star CXOU J061705.3+222127, the collapsed remnant of the stellar core. IC 443 is one of the best-studied cases of supernova remnants interacting with surrounding molecular clouds..

Klaus Brasch

The Triangulum Galaxy (M33)
© 2015 Eric Marlatt

This was shot about 10 miles east of Flag near the Winona ext off I-40, even with Flagstaff being a dark sky city it's well worth taking short trips out for very dark skies for imaging. This image was captured through an Orion EON 130mm telescope, an AP Mach1 mount, and a modified Canon T3i camera, and surrounded by howling coyotes that make sure I'm awake. It has an exposure time around 7 hours. Image processing was done in Pixinsight to bring out all the detail buried deep in the image.

Eric Marlatt

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