The Orion Nebula

Only about 1,500 light-years away, M42, known as the Orion Nebula, is a bright star forming region that can be seen with the naked eye. It is the tip of the sword just below Orion’s Belt in the Orion constellation. The object is so visible that the Mayan Civilization referred to it as the fire of creation.

December 29, 2023

Added an hour of 3 minute subframes to nearly double the total exposure time to just shy of 3 hours. I was hoping that the longer exposure subframes might help reveal a little more dust and gas around the nebula, but it seems like it really only reduced the noise a bit. I recall watching a lecture from Dr. Robin Glover who stated that this is exactly what would happen! I do think there certainly is an ideal exposure time for each target to optimize the signal to noise per frame, which is then amplified with a higher number of exposures, but of course, this ideal time will vary depending on the target. Seems like the Orion Nebula is a target that really only needs about 30-60 second subframes in Bortle 4 skies to reveal even the faint dust near it!

Technical Details

Imaging Telescope: William Optics RedCat 51 II

Imaging Camera: ZWO ASI533MC Pro

Mount: Sky-Watcher EQ6-R Pro

Filter: SVBony UV/IR Cut 2”

Accessories: ZWO ASIAIR Plus, ZWO EAF, ZWO Filter Drawer (Gen 2)

Software: Siril, Photoshop, NoiseXterminator

Guiding Telescope: William Optics UniGuide 32

Guiding Camera: ZWO ASI174MM

Imaging Dates: Dec. 17, 2023

Frames (gain 101.0) f/4.9 -10c: 205x30” (1h42m) 20x180” (1h)

Integration Time: 2h42m

Darks/Flats/Dark Flats: 60/60/60

Bortle Dark-Sky Scale: 4.00

December 18, 2023

Finally the Orion constellation is becoming visible earlier in the night, and I’m able to start taking some images! Up first in the constellation is the famous Orion Nebula with its vibrant pastel colors and flower-like shape. There’s lots of dust surrounding the nebula, and NASA has even imaged a proto-planetary disk around a star in the nebula. As always, every object could do with more integration time than I’ve taken, so I’ll be sure to add more to this one. I may take some shorter exposures to reveal more of the heart of the nebula, and some longer exposures to get more detail in the gas surrounding the nebula. Eventually, I will try a panorama mosaic stretching from Orion’s belt to the Orion Nebula, just to give you an idea of how much there is to see in this famous constellation!