That first shot there was back on September 29, 5:38am, from near the Arch Rock trailhead, in Joshua Tree National Park. This was my first view of Atlas-Tsuchinshan, two days after perihelion (closest approach to the sun). I had some plans to work on an interesting foreground, but my wife wanted to see the comet, too. That' limited the amount of walking I could go to reach the foreground I envisioned. But it also meant I could share something pretty cool with someone, live. It was a fair tradeoff.
At that time, it was definitely naked eye, but mainly a binocular object. Because it was so close to the rising sun, the sky was brightening as it rose, which limited the length of an exposure before the sky just blows out (flat white, no detail). This was with an 85mm f/1.8 lens, just one second exposure at ISO 1600. No need to track at that short of an exposure.
That second shot was about two weeks later, October 13, about 7:20pm. By then, the comet had shifted to the evening sky, but was still pretty close to the sun, so the sky was again pretty bright, limiting the exposure length. Fortunately, the comet was pretty bright, so you could shoot short. That one was with a 50mm f/1.8 lens, stopped down to f/8 to sharpen up the Joshua Tree leaves. ISO 800, 20 seconds, so still short enough not to need tracking. I wandered across the road from the Ryan Mountain trailhead for this shot, where the ground sloped down a bit and I could get some sky behind the Joshua Trees.
The next one was was on October 14, from Los Angeles' Griffith Park. I had hoped to get a shot of the comet over the Observatory, but did not have the angle quite right. I would have to have set up quite a bit further south for this to work. Unfortunately, didn't have the schedule flexibility to try again, so this is the best I've got. From Griffith Park, it was not naked eye. Then again, in addition to the regular LA light pollution, there was also a concert at the Greek Theater, below the Observatory, so that didn't help.
Light pollution and twilight glow limited exposure length a lot more than from Joshua Tree. This one was one second at f/1.8, 85mm lens, ISO 800. Obvious photographically. Didn't have binoculars, so I can't say how it would have looked that way.
The next three shots were a little less than a week later, October 19, from the Redstone area of Lake Mead National Recreation Area, in NV. From this relatively dark location, the comet was still very obvious to the naked eye, at least until it got pretty low above the light dome of Las Vegas.
The first two of those shots are tracking shots, despite the short exposure. At least that's my recollection. The third of those shots was untracked, but with just a 35mm focal length lens. By then, the waning gibbous moon was high, and lit up the Aztec sandstone formation that is exposed at Redstone very nicely.
It's also the only one that required a bit of a walk, maybe a bit more than half a mile each way. The first two were just from the picnic shelters near the parking lot.
Sort of like the shot with the Joshua tree, this is a shot that I somewhat envisioned before going there, except that my original plan would have been to get out there earlier, with the comet higher, and me closer to the arch. Then I could have shot at more of a verticle angle, blocking out more of the Las Vegas light pollution.
But it, like my morning shot, was a compromise of what I could do and still share the view with my wife. Again, still happy with the results, and happy I could share the experience.
Next up was a shot I took while working at Griffith Observatory. Near the end of one of my shifts on a lawn telescope, on October 22, there was finally a break in the line. The "lawn telescopes" are Celestron C11 telescopes, so 280mm aperture. About 70x with the widest field eyepiece. Shot handheld through the eyepiece, in "night mode" with my Samsung S21, then cropped and processed.
While Tsuchinshan-Atlas was easily naked eye from the Observatory back on October 13 (when I was taking my Joshua tree shot, and the Observatory was hosting its monthly star party), by the 22nd it had dimmed significantly. On this day, it was about 6 degrees above a star cluster called M12, so I found the comet by doing a regular alignment, then had the telescope "goto" M12, then moved the telescope a little more than one finderscope width up in altitude, and slowly scannd around that area. I could barely see it in the finderscope, and it was far from obvious in the eyepiece. But I did find it, and I was happy to be able to share it with a lot of patrons that night.
A week earlier, it was near a different star cluster, M5, so I was able to use a similar trick to pick up the comet when it was a little brighter. But there were no breaks in the line that night, so I didn't have an opportunity to try to get an eyepiece shot.
My last three shots of Tsuchinshan-Atlas were taken on October 28, from the Ryan Mountain trailhead.
These were all driven shots, meaning I had a mount tracking to compensate for the earth's rotation. The exposures were also a lot longer: about 60 seconds. They were also taken through a small telescope, an 80mm Astrotech doublet refractor, with an f/7 ratio, but using a .8x reducer, to produce a final focal length of 448mm, and an f-ratio of 5.6. So that's effectively a moderatly longer, moderately fast telephoto lens. ISO 1600 on the second and third from the last, and ISO 3200 for the last one.
There's a little bit of trailing, but I'm pretty happy with the results.
At this point, I did not consider Tsuchinshan-Atlas to be naked eye, and it wasn't particularly apparent in the binoculars, either. Would have still beeen visible, perhaps pretty nicely, in a larger telescope, though.
I had hoped to be able to show the comet to visitors at Sky's the Limit the previous Saturday, but the forecast was pretty negative, so I decided not to make the drive out there. Ironically, it actually turned out pretty clear out there that night.
They had another public event tonight (November 2), but I had some housekeeping matters that prevented me from being able to leave early enough to make that. Would have been tougher to find, but I'm pretty sure I could have found it in my dob, once it got dark. Oh, well.
Likely the won't be taking any more shots, although it will still be within range of my photo set up next week.
I've taken a handful of hikes over the past few months, some in connection with my telescope trips. I'll try to post them asap, but I'm pretty limited on when I can write and edit photos, now. Still, hope to be back with posts a lot quicker than the last gap. Until then, happy trails, and clear skys!
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