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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About a year ago, I picked up a Skywatcher 100ED: a "slow" (F/9) 100mm refractor. I haven't written much this year, but wow: suffice it to say, I rarely use any other telescope (and when I do, I come away disappointed). The refractor cools down quickly, throws up wonderful views, and most importantly: never gives less than optimal performance. The only drawback is the length of the tube, which makes it harder to transport and heavier to mount. This past spring, I was lucky enough to design and teach a dream course: "Mars and the Moon in science, science fiction, and society." I asked my students to join me one night to look at the moon through three telescopes: my 100ED, my older AR 102, and a colleague's beautiful, homemade reflector. Students were to find a feature on the Moon and then write about its history: not only how it was created by natural forces, but how it's been perceived, explored, and imagined by people. The night was a smash hit: lots of amazed expressions, and later, plenty of great essays. Of the three telescopes, the AR 102 was clearly a notch below - and its focuser gave us plenty of problems. This summer, Mars reached a very favorable opposition, not long after I wrote about it for the book I'm working on. When I lugged out my C8 to have a look - at around 4 AM! - it instantly (and I mean instantly) fogged over. There is nothing worse than waking up early, walking with 40 pounds for 15 minutes . . . and then having to turn right back immediately after setting up your telescope. From then on, it was all refractor, all the time. Using the 100ED, Mars typically looked like an angry orange ball, shimmering and sometimes boiling near the horizon. Yet now and then I caught fleeting and often uncertain glimpses of what I supposed to be the planet's famed dark streaks and splashes, including - I thought - Syrtis Major. I might even have made out a polar ice cap. My goal for the summer had been to see these sights with no ambiguity at all, so I came away a little disappointed. Mars is hard when it's so near the horizon. Maybe the view will be clearer in 2020 . . . and maybe I'll have even better gear then. One thing is certain: the 100ED is a wonderful lunar telescope. Things never looked so sharp through the C8, nor did the hues include such subtle gradations of grey. I've also never seen Saturn look as good as it did through the 100ED. The Cassini Division neatly divided the rings, and the color was a wonderful, very pale shade of yellow. Glorious. After one night of rooftop observing, I saw something I didn't expect: a brilliant green meteor - or meteorite? - flaming through the sky. Given that we live in Washington, DC - and given the present state of geopolitics - I was momentarily alarmed. But what a sight! Come winter, I wanted to try my hand at something that never really interested me before: multiple star systems. The prospect of seeing a couple stars next to each other never really did it for me, but then few deep space objects are easier to observe from the city. My primary target was Gamma Andromedae, also known as Almach, an apparent double (we now know it's a triple) star system with wonderfully contrasting colors. With Almach riding high in the sky, I had a look one frigid evening. Immediately, I got it: there was something about seeing two incredibly different stars next to each other that's just so beautiful, especially through a refractor. And it sparks the imagination to think about the view from an orbiting planet. Lately, my two-year-old daughter has become ever more interested in astronomy. She loves looking at planets and galaxies in the books I have lying around, she's learned the phases of the Moon, and she's decided on a favorite planet: Jupiter. She's even insisted on having a picture of Jupiter on her bedroom wall! Maybe, in a year or two, we'll have a chance to look through a telescope together. After a hot, clear day that lacked the crushing humidity I've come to associate with DC summers, I decided to take out my new 4-inch, Celestron Omni XLT refractor. Mars was just a few months from its opposition - its closest point to Earth - and it was fairly high in the sky. Saturn was close to the horizon, but still easily visible. I'd say seeing was around a III, and the transparency of the sky was around 2-3, owing to all the light pollution we have down here. I set up my telescope in front a few apartment buildings, on a grassy knoll below an opening in the trees.
I started with Saturn. With a 25 mm eyepiece, my magnification was around 26x. I could clearly make out Saturn's rings and at least three of its moons, but little else. I plugged in a barlow lens and a 7 mm eyepiece. That increased my magnification to 133x. Now, the view was magnificent. Not only did I clearly discern the Cassini Division - a gap in Saturn's rings about as wide as the United States - but I also spotted a mottled grey cloud belt near the planet's equator. It was, by far, the best view of Saturn that I've ever had. Next, I turned to Mars. By late August, the apparent diameter of the planet was around 11 arc seconds: roughly half as big as it gets near its opposition, but well over twice the size it will be in January. Using the same eyepiece, lens, and magnification, I clearly made out the planet's gibbous, waxing disk. As I watched, the atmosphere above me stabilized and a dark surface feature on Mars shimmered into view. It was very indistinct on the little globe, but definitely there. After about half an hour, Washington's resident Asian Tiger mosquitoes found a way through my repellent. I got a few last glimpses of Mars before they hounded me inside. Overall, this was one of the best observing sessions I've ever had. Until now, I'd never (clearly) identified the Cassini Division, or made out dark patches on Mars. I distinctly remember eying Mars with a 12-inch reflector I used to own, and seeing nothing more than a boiling red ball. The optical quality of my little refractor really impressed me. I didn't notice any chromatic abberation, not even on bright Mars. Everything else is a little sketchy, however. The diagonal was a child's toy, so I quickly replaced it with something better. The focuser isn't much better, and I can't afford to update that. The mount is also a bit wobbly. It's light, at least, but it's awkward and therefore surprisingly difficult to carry. Summer observing in Washington can be hard, given the heat and mosquitoes, but I'm glad I stepped out tonight. |
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