This years’ time in dark skies has been few and far between…the two nights during our June trip to Powderhorn BLM land had been the only time to date…making the August trip seem like a “must go"
Dark Skies – Comanche National Grasslands, CR 24.3 Springfield, Colorado
This years’ time in dark skies has been few and far between…the June trip to Powderhorn BLM land had been the only time to date…making the August trip seem like a “must go.” But yet again, Mother Nature made it difficult with forecasts for thunderstorms, rain, thick clouds at every dark skies location within a 300 mile radius. Finally, the weekend before our planned Thursday departure, we saw a ray of hope…at Comanche National Grassland…but those clear skies came with 100+ degree daytime temperatures! We’ve tried that before and it’s unbearable for man or beast (especially Paul and Zeus!). After many alternative plans, we finally settled on Plan K (as in not Plan A, Plan B, Plan C…) – to stay in a hotel in Springfield, Colorado and drive onto the Grasslands for a night of shooting on Friday. Then spend Saturday making our way to Albuquerque for an anniversary dinner (#36) at Sal’s Ristorante.
We arrived in Springfield at about 1300 and surveyed the back lot of the hotel. That would be a NO – the front desk agent, John, said they couldn’t turn the lights off due to security reasons and the entire area was “lit up like a Christmas tree” anyway. So, we drove to Picture Canyon – our normal shooting spot – beautiful, hot, and windy – a 40+ minute drive from the hotel and no cell coverage. The idea of my going solo there was vetoed outright. On the way back to the hotel, with the disappointment building, we stopped at the Forest Ranger’s Station and asked for closer Grassland locations. The agent there showed me a map of checkerboard areas throughout the Springfield area – National lands interspersed with private property. He also mentioned that Google maps will show the National lands in a different color, so you can confirm that you’re not on someone’s property. He suggested heading west on Hwy160 and then south on one of the county roads to find a suitable spot.
After a trip down CR17 and CR19, finding a couple of spots that might work we made one last try down CR24.3 and found an area that was on the map as Grasslands public land, had an access gate, flat ground, and most importantly – cell phone coverage, so Paul and Zeus could stay in the hotel while I spent the night out imaging.
Adapt and overcome!
I headed out to that spot after dinner to set up, departing the hotel at about 1900. I got to the spot and started unloading and setting up. My first discovery was that in the interest of saving space in the Pelican box I use to transport my optics, I’d decided to only take one guide scope, yep, the wrong one! I had the guide scope that had the connection plate for Big Bertha or Big Zeus, while the guide scope with the connection for the Southern Cross was sitting on the dresser at home! Okay, don’t panic – this is a good mount, I can shoot up to a 3-minute exposure without a guide scope (or so I thought). The second discovery was that I had arced the new 12-volt gel battery that Paul had set up for the Southern Hemisphere trip – so when I plugged into it there was no power. Luckily, I had insisted we were not going to do our initial operational testing of that battery out in the field during precious dark skies operations, so I had brought along my front-patio car battery as a back-up. I’ll adjust the shot plan for the night and be on our way (or so I thought)…
I had difficulties polar aligning – although the latitude is 37°, with the mount at 35° Polaris was still not exactly aligned. Okay…we’ll go with that being close enough. I abandoned the idea of getting another night’s data on SH2-129 Flying Bat (which requires 10 minute exposures to bring out the OU-4 Squid portion of the image) and adjusted to IC1396 Elephant Trunk, a relatively bright target (Mag = 3.5). Because I had been experimenting with 2×2 binning, having read that it basically has the same effect as doubling the exposure value, I decided to use that setting. I forgot to set the camera gain before starting the sequence, so it defaulted to gain=158, no offset. I imaged from approximately 2100 until the meridian flip at approximately 0100. (Captured the Milky Way with the Canon EOS Ra with 14mm lens on the star tracker, while the Elephant Trunk capture was proceeding.) While my initial plan was to image the Elephant Trunk all night long, I decided late in the game (about the time I was going to do the meridian flip) to maximize the dark skies targets captured during this one-night trip and switched to the Flaming Skull Nebula.
The capture seemed to go well (the bright side (?) being with no guide scope, there were no lost guide stars to terminate the sequence!) but when I got home to begin the APP stacking process I struggled mightily. During the registration process, the process would fail – it would show one subframe that was the culprit, but when that file was deleted it still wouldn’t complete the registration step. I deleted the bad subframe and tried again – to another failed registration. For Elephant Trunk I ended up selectively deleting subframes that had a quality score substantially less than the registration frame (i.e., in the 3000’s or less). So, although I captured 78x3min for a total exposure time: 3:54 hours in the field, after culling the images that wouldn’t register, I ended up with 35x3min for a total exposure time in the image of 1:45 hours. For Flaming Skull I had noticed how many subframes APP had registered before it failed (52). So in the setting for how many light frames to stack, I selected to stack the top 50 subframes and that finally produced a result. So, although I captured 86 x 2minute exposures (3:54hrs), the final stack only contained 50/83 (1:45hrs).
...and the results show
Even given the lack of data – the richness of the colors and the ease of processing reemphasizes the fact that dark skies ARE better!
Below are peaks at the Elephant Trunk and Flaming Skull – the full target fun facts, capture and processing notes, and additional images are in the portfolio/gallery here…
IC1396 Elephant Trunk: https://beersastrophotography.com/gallery/deep-space-item-test/
NGC7822 Flaming Skull: https://beersastrophotography.com/gallery/ngc7822-flaming-skull-nebula/
Milky Way Core: https://beersastrophotography.com/gallery/milky-way-over-comanche-national-grasslands-springfield-colorado/