It may be no surprise, but when I have to use one telescope these days, I take my Takahashi FC-100DC. It's wonderfully lightweight, it's beautifully made - in a way that's really growing on me - and gives views that seem remarkably bright for its aperture. By comparison, the Moon gets noticeably dimmer and yellower when I get past 150x or so in my TV 85; it stays as bright as ever at over 200x in the FC-100DC. At just after 9:00 PM on October 14, while on our observation deck with my Takahashi, I had one of the most bizarre and, for a moment, frightening sightings as an amateur astronomer. As I observed the Moon at around 150x, a perfectly black, sharply defined circle abruptly appeared in front of the white disk. It began to slowly move across the Moon, looking for all the world like a planet transiting in front of the Sun. Then, when the circle reached the edge of the Moon, it stopped and then started moving in the opposite direction across the surface of the Moon. It meandered slowly and smoothly around the lunar disk. When I increased the magnification, the circle got bigger; when I reduced magnification, it got smaller. Rattled, I checked the telescope thoroughly and found it in like-new condition, with no dust or blemishes on the lens. Eventually, I looked away from my eyepiece. When I looked again, the circle was gone. I was flabbergasted. What did I just see? I couldn't wrap my head around it. Bizarrely, I'm just now researching and writing about the history of perceived changes in lunar environments, including those often called "Transient Lunar Phenomena" (TLP). Observers who thought they'd seen a TLP in the past often expressed shock. I felt that too. The only explanation that made a modicum of sense was a balloon, at just the right distance away. But what could explain the seemingly deliberate motion of that little circle? My imagination went wild. I packed up quickly and recounted the sighting to my wife. I wrote a short report on CloudyNights, the popular astronomy forum, and then sent a message to the Central Bureau for Astronomical Telegrams. Within minutes, I received a reply from Michael Rudenko at Harvard. Apparently, I had observed one of Google's stratospheric balloons, deployed for Project Loon: an effort to bring the Internet to underserved regions. Two years ago, another sighting apparently perplexed an observer in Puerto Rico. What a coincidence - and what a reminder of just how many machines we've placed in the atmosphere, in space, and on the edge of space and atmosphere. Just before observing the Moon, I did manage to catch a glimpse of Almaak (Gamma Andromedae), the apparent double star that is really a quadruple star system. I never really got the appeal of double stars, but I'm starting to now. The contrast in colors is beautiful, as is the thought of sunsets on orbiting planets . . . .
Quite a night, overall . . . and quite a telescope.
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So the Takahashi, it turns out, is a pretty good telescope. I've now used it a few times on my observing deck, after amassing all those little accessories, and systematically exchanging my good-but-not-great eyepieces for top-of-the-line TeleVues. Jupiter and Saturn - both near their oppositions when I received the telescope - can in good seeing look even better (!) through the Takahashi than they do through my TV 85. The difference is not huge, however, and the TV 85 does have some advantages over the slightly bigger FC-100DC. It cools down almost instantaneously - the Takahashi might take just a bit longer - and it has a wonderful size and feel: compact but solid, like a piece of metal. Visually it's no slouch at all, and I just like the TeleVue mechanics a bit more than the Takahashi equivalents. The dual-speed TeleVue focuser, for example, is just so smooth, whereas the single-speed Takahashi equivalent is stickier. There are also so many little extenders and parts to screw and unscrew with the FC-100DC - Takahashi sure doesn't make it easy to decipher what should and shouldn't be attached to the telescope - and even when I've got the right setup some of my eyepieces still don't come into focus. It will be better on good nights than the TV 85, and perhaps meaningfully better on red objects - like Mars - given that red light does not quite come into focus in the TeleVue as it does in the Takahashi, but it's more finicky and I'll use it less frequently. You just can't beat the TV 85 for grab-and-go . . . but it sure is nice to have the slightly bigger Takahashi. I've been experimenting with iPhone astrophotography. The image above is the best I've taken of Saturn so far. If I try to take a picture, all I get is a brilliant white oval. But if I take a video, I can usually get a few frames that look like Saturn - albeit so much blurrier than what I see through my eyepiece. Up on my observation deck, the planets bounce around wildly in the currents coming off my building - and in the currents of our often-turbulent atmosphere. My iPhone naturally translates that bouncing into noise: the blurriness in my attempted astrophotographs, and the corresponding lack of contrast. Jupiter is completely washed out, no matter what I do. But Saturn is just dim enough and high enough in contrast to look like something. In the above picture, you can make out the Cassini Division and some cloud belts. Not bad for an iPhone production! Lunar photography is a bit easier. Views through my telescopes are incredibly crisp - razor-sharp on the best nights - but of course all that sharpness disappears in the pictures. Yet the Moon is so big and the views are so clear that it doesn't matter as much as you'd think. Sometimes the pictures are still quite satisfying. I really liked taking these pictures of the lunar terminator, which feature a crater, Gassendi, that was the focus of nineteenth- and early twentieth-century debates about changes in the lunar environment (and the possibility of lunar life). You can also see just how bright it can be on our observation deck. I'm very much looking forward to when the mosquitoes have abated enough for me to try a local park.
It's been a while since I wrote. I've come to realize that, with young kids, I just about never have the time to do something as decadent as write for fun. And I certainly don't have time to write long articles purely for myself - or the occasional wayward visitor. Yet here I am, writing again while rocking my infant son to sleep. Over the past few years, I've gone through my share of equipment and seen so many beautiful sights. I've learned a lot about what equipment works for me in Washington, DC, and what I most enjoy seeing. Here's a little list: 1. Aperture is absolutely, most definitely, positively not king, and don't be fooled by anyone who tells you it is. Aperture is one very important factor to keep in mind when selecting optical instruments, but by no means the most important. I received tenure this year (!!!), and shortly after I did I had what appeared at the time to be a great opportunity to visit the southern hemisphere. That fell through - I couldn't get a Yellow Fever vaccination on time - but not before I'd used some funds to buy what seemed to me to be the perfect travel telescope: a TeleVue 85. I remember seeing advertisements for TeleVue refractors as a kid, and wondering why anyone would spend so much money on a telescope so small. I went ahead and bought a VAMO traveler - a wonderful little mount - and a carbon fiber photography tripod. Together, the whole setup weighs about 14 pounds. When everything was ready, I walked outside onto the observation deck of my building to catch a glimpse of Jupiter just after its opposition. High, hazy clouds rolled in just as I stepped outside, partly obscuring Jupiter. Yet I set up my telescope - in just a couple minutes! - and had a look anyway. It was hard to make out many details, and I packed it in before too long. A few days after, I walked out on a truly clear night. This time, my first stop was the half moon. I was absolutely floored. I'd never seen the Moon with such astonishing clarity and contrast. I'd thought my Skywatcher 100ED gave me great lunar views; clearly, I was missing out all along. Turning to Jupiter gave me a hint of detail that I'd never seen before. Saturn, despite being very low on the horizon, was a beautiful sight near its opposition. Lately, I've written an awful lot about nineteenth-century astronomers - amateur and professional. Back then, many debated whether small or big telescopes offered the best planetary views. I'd assumed that the debate had been sparked by tensions between amateur and professional astronomers (the amateurs typically couldn't afford the gear that professionals used, with some big exceptions), rather than real experience. Now, I realized I'd been wrong. It occurred to me: if this little telescope gave me the best planetary and lunar views I'd ever had, why did I have so many bigger scopes? It didn't help that the little instrumented exuded quality like nothing I'd ever owned. Everything about it made it an absolute joy to use. The following night I lugged out my 8" Edge SCT, on its heavy mount and tripod. This time, the whole setup weighed in at about 33 pounds. Seeing was better than it had been the night before. I had to know: with an aperture of 200 mm, would it show me even better views than the 85 mm refractor? No. The views were brighter, for sure, but they lacked the crisp contrast that the refractor provided. I saw a good deal less detail on Jupiter, and the Moon wasn't nearly as detailed. I was actually a little embarrassed when two neighbors asked to look through the telescope, because I remembered the glorious views from the previous night. I felt a pang of regret that I hadn't brought the TV 85 instead. That brings me to the second, related lesson: 2. Cooldown, weight, ease of use, contrast (versus brightness), fit and finish, and perhaps above all the local environment (on the ground and in the air): all can be as important as aperture. One reason that views through the Edge quite literally paled in comparison to those through the TeleVue is that the Edge hadn't yet acclimated. Not surprisingly, the Edge can take over an hour to reach thermal equilibrium. These days, with a newborn and a three-year-old, an hour is usually all I have to observe. Moreover, even on a simple alt-azimuth setup, it takes a good 10 to 15 minutes to set up - compared to fewer than 5 with the refractor. It turns out, all of that matters a great deal to me. So does weight. The easiest way for me to use a telescope is to lug it up several flights of stairs. Observing on the observation deck of my building, I've found, can attract a lot of unwanted attention. I like outreach, but observing for me is most enjoyable when it's just me and the sky. Maybe my kids will make me reconsider that feeling, when they're old enough. Anyway, my "best" regular observing sites - they're still far from ideal - are a 15-minute walk away. It's just not haul 40 pounds of gear for that long - especially when you aren't sure that your telescope will acclimate before you have to pack up. That's the other thing: I hate collimating. Yes, I've become pretty good at it, and yes, an SCT doesn't need to be collimated much. But give me a telescope I can set up and look through, right away, with no fuss. Especially when I don't have much time to observe! Then there's our local environment. In the winter, it gets pretty cold here: all the more reason to have a telescope that cools down fast. In the summer, there are mosquitoes: all the more reason to observe fast. The air can be turbulent (though we do have stretches of good seeing): not a big deal when using smaller apertures, but incredibly frustrating with bigger telescopes. In the city, I tend to restrict my viewing to planetary, lunar, double stars, and the really big showcase deep space objects (Orion, for example). In light-polluted skies, I put a premium on pinpoint stars and stark contrast. I've found that high contrast optics can give better views of deep space objects even when those views are dimmer. Lastly, there is just something about a premium instrument that makes you want to use it. Every little thing becomes a pleasure, from unscrewing the dust cap to adjusting the focuser. Yes, it's silly, and yes, maybe it's what you notice when you read too many telescope reviews. But it matters, especially when you're in a hurry. So, my third lesson: 3. I'm a refractor guy, through and through. It's worth noting how personal this lesson is: completely attuned to what I value, where I live, and my life circumstances. That it's taken years and more money than I care to admit to reach that lesson does make me resent the ubiquitous comments on astronomy websites that tell people what telescope to buy. No, the best answer is not always the biggest you can afford. After taking out the Edge that final time, I went on the kind of binge that I still can't believe I had the energy for. I sold just about every piece of astronomy gear I had, including four telescopes, three mounts, and two tripods. I have to say: it often hurt. Away went the telescope - the C8 - that I'd always fantasized about having. Away, too, went a really nice 100 mm refractor: my Skywatcher 100ED. If it couldn't offer better views than my much smaller and more portable TeleVue, it had to go. But I didn't want to sell for the purpose of selling - nor did I feel comfortable with just one telescope. Once I'd ditched just about everything, I agonized over what second telescope I'd like to have. It had to be relatively small, while offering something that the TeleVue didn't - or at least, giving a little something extra that the TeleVue couldn't. I wanted something that I might use when the seeing was really steady, even if it was a bit harder to use. Ultimately, it came down to two choices: a Skywatcher 120ED and a Takahashi FC-100DC. Both are refractors, of course. The Skywatcher is a good deal bigger and slightly less expensive. The Takahashi technically gathers less light, but the optical quality is such that it might actually offer better views of just about everything - especially planets. I eventually settled on the Takahashi. Other 100 mm Takahashi variants have longer focal lengths, which makes them better attuned for planetary observing. Yet the difference is negligible, and the shorter focal length of the DC makes it a more versatile telescope for deep space observing. It also makes it much easier to mount: I could easily use the same mount I purchased for the TeleVue 85. So, to my astonishment, I made a purchase I never expected to make: I bought a Takahashi, one of the most celebrated telescopes in the hobby. My dream is to use the Takahashi for planetary, lunar, and double star observing, especially when I have a bit of extra time, or when the weather is nice enough for a walk to a nearby park. If I have time - hah! - I'll write an update on how it works for me. For now, I'll collect all the little accessories - from a diagonal to tube rings - that Takahashi chooses to sell separately.
It's been quite a journey, but I hope I now have telescopes to last a lifetime. At least, until the next big purchase comes calling . . . . |
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