8 January 2021 Imaging Session – Joshua Tree National Park

Date:	January 8-9, 2021
Location:	Cottonwood Spring, Joshua Tree National Park
Observing Time:	19:00 – 3:00 ( UTC – 8)
Weather:	Clear, Calm w/occasional breeze, Humidity >15%, Seeing – 3/5
Temperature:	65°- 42° F (18° – 5° C)
Bortle Scale:	3

Object	Constellation	Frames Layered	Combined Exposure
“Sword of Orion 2021”	Orion	13	~60 min
Rosette Nebula (C49)	Monoceros	3	20 min
M46	Puppis	2	15 min
M81&M82	Ursa Major	7	~ 60 min
M97& M108	Ursa Major	3	26 min
Leo Triplet	Leo	4	45 min

Notes:

While the campgrounds in the National Park remained closed due to the ongoing pandemic, the park roads remained open, as did the hiking trails and respective parking lots. A lot of RV’s and campers instead pitched tents on the BLM dirt roads located just south of the park entrance.

Anytime I go to the park it’s a gamble on if hikers will stay overnight in the parking lot, but this time I lucked out and had the entire lot to myself after dark. Aside from a group of friendly college students I presented the constellations to before they left, everyone there decided it was too cold and dark to stay – no complaints from me on that end!

This was a planned shoot, so I wanted to shoot objects in a certain order. The “magnum opus” of the night was of course another crack at the Orion Nebula with the intention of putting the 2020 “Sword of Orion” shot to shame. Even though the 2020 version was a huge improvement over older shots, I wasn’t too happy with the background stars, some of them near the edge clearly having coma issues and the star Hatsya (ι Ori) sets of spikes instead of one! I also wanted to show MORE nebula structure that was missing in the 2020 version. I also didn’t have a coma corrector then!

It’s easy to just overexpose the trapezium section – which a lot of photographers do so they can expose enough for the rest of the gas cloud – but the challenge of layering exposures that show those familiar stars on top adds more depth to the image, but makes it look closer to how you’d see the structure with just your eyes if they could see the color! All it takes is some good Photoshop skills and a careful application of the eraser brush!

I planned on doing a mosaic for the Rosette Nebula, but when I tried doing so, the upper frame was not rotated correctly, and thus it wouldn’t be a good stitch. I then decided the initial middle frame was a good enough representation, as it still looked like a “rose” like it’s namesake.

After successfully getting good data for the pairing of M81&M82 plus M97&M108, I ended the night with the Leo Triplet. The waning crescent moon rising around 3:30 am was going to mean “the night is over for me.” After 8 hours of imaging I was definitely feeling tired!