Telescope Demonstrating 145 Miles From LA | 8-9 May Imaging Session

A slight break In the “routine” that made this night feel like I was back doing a normal shift on the Griffith Park lawn… only a matter of time before that reopens.

Date: May 8-9, 2021
Location:Cottonwood Spring, Joshua Tree National Park, CA
Time21:00 – 4:00 (UTC-7)
Weather clear, calm, 75°-60° F (23°-15°C)
Bortle Scale3

Equipment Used

  • 8″ (203 mm) f/4.9 Newtonian Telescope
  • Atlas II EQ-G Mount
  • Starshoot Autoguider
  • Nikon d5300

What Did I Shoot?

ObjectCommon NameConstellationFrames
α BoötisArcturusBoötis15 mins
ω Centauri
C 80
NGC 5139
Omega CentauriCentaurus190 seconds
M 6 Butterfly ClusterScorpius412 min
M 7 Ptolemy’s ClusterScorpius521 min
M 8Lagoon NebulaSagittarius420 min
M 10Ophiuchus416 min
M 16Eagle NebulaSerpens527 min
M 20Trifid NebulaSagittarius624 min


More and more people who know me from another job have been catching on when I usually head out to Cottonwood Spring to do these sessions, as I always say, “every new moon.” This time, two families came out with me and experienced the sky. As both of them have fathers who are prospective astrophotographers – as in, they are have good DSLR cameras but wanted to see first hand what telescope photography is all about.

While it’s not uncommon for hikers and those enjoying recreational activities in the national park to see my set up and approach me out of curiosity, this time, the small gathering of those in chairs definitely added to it. Some would even stick around and listen to me presenting, and at times I forgot they were still around.

And for those wondering about anything Covid pandemic related: not only are Californians doing a decent job of getting vaccinated, but the state has overall been getting less restrictive as a result. It really didn’t feel like anything hanging over our heads. Plus it helps that stargazing IS a social distancing activity in itself! It was a far cry from this time last year, when anyone I encountered in the California desert was afraid to approach me due to the concerns and health measures, plus the big national parks in California weren’t even open then.

Due to the families, and all the people passing by who got to enjoy live telescope views of M51, the Virgo Cluster region, M13, M44, and M104, plus my usual constellation tours of the sky, it once again felt like I was doing my Telescope Demonstrator job at Griffith Park.

At about 11 pm (23:00) is when I began to switch into imaging mode, and the guests made their way back home.

Before people even arrived, I had diligently made sure the telescope was level, balanced, and the mirrors were secure and collimated – I did not want a repeat of a couple failed imaging sessions over the past couple of months.

The software ended up telling me at the start that I was less than one arc-minute off from perfect polar alignment, which of course is one of those things that any telescope astrophotographer feels an accomplishment over.

Omega Centauri didn’t look great at first on my Nikon’s screen when I did the 90 second guided shot. But because it’s a very low target in the sky when viewing from 34 N latitude, (like so low that it was easy for a child to walk in front of the telescope tube and block the light), it was somewhat expected. But when I later processed it, the image turned out way better than I expected.

Arcturus had some red noise issues in the raw photo, which I believe actually came from the lower caliber battery I was using. Even though it’s technically a red giant star (or turning into one), it looked visually white through my Newtonian, and the 5 minute test exposure gave it an off-white color. But everything looked sharp.

However, M10 started showing guiding issues, which then led me to check the alignment and learn I was now off by 11 arc minutes… what happened? It turns out the left azimuth knob used to fine tune the mount for polar alignment was loose, which caused the mount polar alignment to eventually drift off. OOPS!

But because it was after midnight, and I only had a few dark hours left, I settled for being off by 5’x10′ which wasn’t horrible.

Everything else after that was smooth sailing, and to play it safe I kept the sub exposures down to 3-6 minutes for the most part, though M16 did manage a successful 9 minute sub.

With the entire parking lot to myself, that meant I could blast my space metal playlist on my bluetooth speaker without guilt! As the night ended, Epica’s song Kingdom of Heaven Part 3 made a very fitting last song.

And of course, once again to cap off the night, the Summer Milky Way above my telescope!


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