Here in DC, it's hard to avoid thinking obsessively about the demoralizing news from eastern Europe. Yet the skies cleared recently, enough for an hour or two of late-night escapism. A few nights ago, I slipped out with the Takahashi. Transparency was really good but seeing was far worse than average, and since it was well below freezing I didn't want to stay out for long. Still, the FC-100DZ performs so well in poor seeing that I still managed to have a nice view of the waning Moon from my new backyard. Conditions were similar last night, with good transparency and poor seeing. By 10 PM the Moon was only just beginning to rise, which means that the sky was still quite dark. The Big Dipper was climbing towards zenith, and that gave me a chance to image Bode's Galaxy - M81 - with the EVScope 2. I tried imaging M81 with the EVScope 1 on several occasions last year. I have a particular fascination for barred spiral galaxies like M81, which at 12 million light years away is a little smaller than our galaxy. I'm not sure where that comes from exactly, though the shape is certainly aesthetically pleasing. As a kid, I vividly remember admiring a picture of a barred spiral - was it NGC 1300? - that really captured my imagination. Then I found out, when I was a little older, that our own Milky Way was actually a barred spiral, not the conventional spiral it's usually portrayed to be. That was a fun little eye-opener for me. In any case, observing Bode's Galaxy with the EVScope 1 was a disappointment for me. The galactic nucleus is bright enough, but the spiral arms are subtle and easily lost in the downtown DC light pollution. I never got much more than a blurry circle. The EVScope 2 allows me to take longer exposures, however, and that plus its higher resolution made me hopeful of a better outcome last night. And indeed, this is far better than anything I managed with the EVScope 1. To capture this 26-minute exposure from my backyard in downtown DC, after just a few seconds of setup time, seemed borderline miraculous to me. This time, I also peered through the new and improved eyepiece of the EVScope 2. What a huge improvement! Looking through the eyepiece of the original EVScope was like looking down through a barrel at a tiny, pixelated square. But the eyepiece of the EVScope 2 feels like . . . well, a proper eyepiece. The view is circular, it feels close, and it's noticeably higher resolution. In fact, it looks more impressive than the image above. The gallery above shows the difference between unprocessed 9-minute, 18-minute, and 26-minute exposures. The difference is subtle, but it adds up. Note the relative lack of a diffuse glow around the galaxy. With the EVScope 1, that glow used to creep into my exposures after a few minutes, as a result of light pollution here in DC. That's one reason that my views were so much better out of the city. The EVScope is much better at filtering out light pollution, which makes it a far more capable telescope for deep space observing in the city.
When I ranked the telescopes I'd owned last September, the EVScope 1 came it at number 7. I'd rank the EVScope 2 a good deal higher - definitely in the top five, maybe even the top three. It's that good.
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With a backyard, I'm able to do something I don't think I've ever tried before: observe the Moon before sunset. I just could never imagine doing that in my old home. On my former rooftop, I might have been besieged by my neighbors, and in a nearby park, hounded by dogs. But now, at last, I can relax behind a fence, set up a nice refractor, and enjoy the Moon at my leisure with a beer in hand. It's beautiful. During my move, I'd noticed that the focuser on my Takahashi FC-100DZ had a little too much give. The culprit, I realized, was a loose screw. Repairing this little issue led me to consider upgrading other aspects of my grab-and-go setup. I parked the telescope inside to attempt to quantify the vibrations I'd long experienced with the Berlebach Report tripod I'd been using. It didn't take me long to realize that, even in a completely wind-free environment, those vibrations were intolerable at high magnifications. I will still need to walk to the parks I've often frequented - my little backyard only reveals so much, and the pockets of sky I can access will close when the trees regain their leaves - so I started wondering: did I need to sell the DZ for a lighter telescope? I hated the idea, but I certainly don't want to haul around the tripod I use with my TEC 140 just to use a four-inch refractor. Uncharacteristically, I wrote a note asking the CloudyNights community for help, and help I received. Carbon fibre mounts, some of the responses stressed, could yield fewer vibrations than my wooden mount. This seemed counterintuitive to me - wood, I thought, tends to dampen vibrations - but I went ahead and purchased an Innorel RT90c Carbon Fiber Tripod. I was skeptical, but sure enough: the tripod just about halved the vibrations I'd experienced. It's also much lighter and more compact, meaning that I now have a more portable and more stable grab-and-go setup. Best of all, I get to keep the DZ: a telescope I love. I took the above picture of the waxing Moon a couple days ago (February 9th), at around 5:00 PM. At the time, seeing was worse than average, but transparency quite good. Note how much lunar detail the FC-100DZ reveal in even poor seeing; it's quite remarkable. Observing at 5 PM gave me a chance to, at long last, share my passion with my kids. My eldest is 5, my youngest 2. Both insisted that they could see craters, though my daughter claimed that the Delos eyepiece was a little hard to use. And it's true: it takes a little practice to know where exactly you should position your eye with a big, complex eyepiece like that. I wonder whether a simple Plossl eyepiece would be a better bet for the kids - and for outreach more broadly. It's what's I use with my students (admittedly, partly because I don't want to risk my pricier eyepieces). It clouded over that night, unfortunately, so I wasn't able to observe after sunset. Yet when I stepped outside the next night to get some air, I realized to my surprise that I could see the Moon setting in the west behind my building. Clouds were rushing in, and the temperature was falling fast. Before my move, I would never have observed in those conditions. Yet now it took me all of three minutes to pop inside, grab my Takahashi, and set up everything up in the only corner of my backyard that still afforded a view of the Moon.
Neither the telescope nor my eyepiece had cooled down, and seeing was atrocious: about as bad as it gets in DC. But as the picture reveals, there was still plenty of lunar detail to be seen. The Takahashi excels in good seeing, but I've also found - like others - that it manages to outperform just about any comparable telescope in poor conditions. I'm hopeful that, in late fall, winter, and early spring, I'll be able to use my backyard to study the Moon far more consistently than I ever have before. In that effort, I suspect the FC-100DZ will be my most important tool. Two things have kept me from posting - and observing - these last three months. First: the weather. This has been about the worst stretch of cloudiness and terrible seeing that I can remember in DC. On the rare nights that seemed promising, conditions worsened just as I was about to step outside with my gear. I remember a similar though slightly less atrocious stretch of bad weather last year at around this time, when I was so impatient to see whether my new Takahashi FC-100DZ really provided better views than the Takahashi FC-100DC I had just sold. Now I wonder: is this the start of a new trend, or perhaps a regression to a mean that existed before I started observing whenever I could? But second, I bought a home. That turned out to require a lot of work - more than enough to keep me in, even if the nights had been clear. The new place is a condo with a fenced-in backyard. A backyard! It's what I've always dreamed of. Okay, it's small, and it's mostly for the kids. But when my wife saw the yard for the first time, she reported a gap between the trees that "might be good for your telescopes." My heart skipped a beat. Can you ask for anything more from a partner? We moved in just two weeks ago. It's been quite cloudy since, but then, last night, the clouds parted, and the forecast called for better than average seeing and transparency. So I woke up at 4 AM, ready to go. I didn't have to go far: whereas I've long had to walk for ten or fifteen minutes to reach a nearby(ish) park, now I just step out the back door. What a thrill! Admittedly, the backyard affords only pockets of open sky, nearly all of them facing east-southeast. When the overhanging trees sprout their leaves this spring, most of those pockets will fill up. For now, however, I was thrilled to see Ursa Major, Hercules, and Lyra all hanging overhead. There are some streetlights nearby, but they're not blinding and their light points down at the ground. For a condo backyard, you can't ask for much more. I slipped outside with my EVScope 2. That's right: I've upgraded from my first-generation model. The sequel has a higher-resolution sensor that shows more of the sky, along with a much-upgraded eyepiece. Those were exactly the upgrades that I've yearned for, so when I heard about them I had to pounce. The EVScope 2, however, is not exactly cheap. I bought it at about $1000 more than the original, which of course I had to sell to make the purchase remotely possible. When I stepped outside, it was -7 degrees Celsius - that's about 19 degrees Fahrenheit. To cover the approximately 30 degree (Celsius) delta between inside and outside temperatures, the EVScope required a good thirty minutes to acclimate. When I tried to capture an image before it had cooled down, it was predictably blurry and unsatisfying. But after the telescope had reached ambient temperature, the view was rock-steady. The EVScope 2 seems to align itself even more easily than the original. It honestly takes no more than ten seconds or so, and then it's ready to slew anywhere in the night sky. Objects also appear more consistently centered in my view after the telescope finds them. I'm not sure what accounts for this; is there really something about the EVScope 2 that could be responsible for it? I'm not sure. Maybe I was unlucky with my first unit. But the improvement sure is handy. M51 - the Whirlpool Galaxy - is always a favorite target. Last night it was a little close to the balconies above us, which required me to reposition and realign the telescope a few times to get a decent angle. Then, in just six minutes, I got the above picture. I think it's about as good as the image I got in Lewes, Delaware last summer, with the EVScope 1 under far darker skies. I think the new version handles light pollution far better than the original; certainly it seems to take far longer exposures before the image starts brightening around its edges. The amount of detail on M51 is really extraordinary when you consider it took just a few minutes to get that shot in a light polluted, Bortle 7-8 sky. As readers of this site will know, I get such a kick out of M57, the Ring Nebula. With a four-inch refractor in DC it is just barely - barely - there, and then only with averted vision. A larger refractor shows more, but not much. The EVScope, of course, makes it so obvious, and so colorful, in just a few minutes. The EVScope 2 provides meaningfully less grainy images; the nebula looks smoother here, and much more true to life. As the eastern sky showed its first signs of brightening, I turned to M13, the Hercules Cluster, to close out the night. There's just something about a globular cluster that is always such a thrill for me, and of course the great Hercules cluster most of all. This view did not disappoint: easily the rival, I thought, of what the EVScope 1 revealed under far darker skies. The EVScope 2 seems to more consistently permit longer exposures; I found that my phone frequently lost its connection to the EVScope 1 when my exposures passed ten minutes or so. Maybe that was just my unit, but still: it was nice to easily cruise on to 12 minutes on an object like M13.
I kept slipping back inside to warm my fingers as the telescope started taking exposures. That's one wonderfully convenient luxury of a backyard. Still, I didn't lose that early morning magic, when all seems still, even in the heart of a city - breathless with anticipation for the rising Sun. There's just nothing quite like that feeling of being outside with a telescope in the hours before dawn, gazing millions of years back in time and space. |
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