Conditions were glorious last night - temperatures in teens, seeing and transparency both above average - and I was feeling surprisingly energetic, so I dragged my TEC 140, DM-6, and Berlebach Uni tripod out the door, and walked 15 minutes to my favorite nearby park. I had about 80 pounds of gear with me, but somehow, last night, I found it quite manageable. It was heartening to know that I could transport the TEC 140 without much more difficulty than I used to haul about my dearly departed APM 140.
When I set up shop I noticed that the sky was strikingly dark, and that the stars and planets scarcely twinkled. I immediately plugged in my highest-power Delos eyepiece - which manages 217x - and targeted Jupiter. What a view! I lost track of how many cloud belts I could make out, and subtle detail was everywhere. I was looking at the same hemisphere I had admired about a week ago with the TEC 140, and that same barge I noticed then was still around. Now the Galilean moons looked even more clearly like disks, and therefore like real little worlds. I decided that the difference between the TEC 140 and the APM 140 lies in the sensation of texture on the planets. More than the APM, the TEC gives me the feeling that the clouds of Jupiter, for example, have depth, which in turns makes it clearer that I'm observing a three-dimensional object. That really makes a profound difference. Both the APM and the TEC provide views that are far better than those of four-inch refractors, including the Takahashi FC-100DZ. There's just so much more contrast visible with the bigger refractors, and on a low-contrast object like Jupiter that means everything. The view of Saturn was a bit less perfect, just like it was a week ago. While I could easily crank up my magnification past 200x on Jupiter - which is usually about the limit in the Washington, DC air - Saturn benefitted from lower magnification. Still, I was struck by the obvious complexity of its ring system in moments of good seeing. It seemed I could clearly make out not only the Cassini division, but at times I got a flicker of brightness variations, attesting to distinct ring groupings of varying brightness. After observing Jupiter and Saturn for a while, I wheeled the telescope east to observe the Pleiades at low magnification, which was pleasant but not noticeably different than it is in a smaller refractor. Then I realized that Uranus had climbed well over the horizon, and in fact that it should now be near 37 Ari, a star of very comparable magnitude (5.75 to 6 for Uranus). I've never observed Uranus before. I've tried to find it, but come up empty time and time again. It's actually a little embarrassing; it shouldn't be that hard to identify. So, this time, with the weather perfect and armed with a powerhouse telescope, I decided to give it a try. The trick was to find Menkar (Alpha Ceti) and Kaffaljidhma (Gamma Ceti) in the constellation Cetus. While these are bright stars - Menkar in particular, at magnitude 2.5 - it's telling that even with atmospheric transparency better than average, I could only barely make them out. DC's light pollution is especially bad to the southeast from my position, which is where the national mall and the rest of the city's downtown area is located. Anyway, once I found those two stars I used them to triangulate Mu Ceti, which at magnitude 4.25 truly was at the edge of my perception. These three stars in Cetus formed a narrow triangle that pointed to Uranus and 37 Ari. In fact, the length of the triangle was actually greater than the distance of the planet from that triangle. Using my finderscope, I searched. And searched. About 20 minutes went by, and no dice: I could see only stars. I started scanning more broadly, thinking I'd done something wrong. Then I checked my star map - which I get through an app called Stellarium - and suddenly it hit me: I'd been looking for something that looked like a planet. But Uranus is so far away - and therefore so dim - that it should really be indistinguishable from a star at low magnifications. My problem was that I had plugged in my 24mm Panoptic eyepiece, which gave me a magnification of just about 40x. I needed to trust my map and really crank up the power on the star that, I knew, must be Uranus. So I did. With the high power Delos eyepiece back in and my magnification at 217x, suddenly the planet became obvious: a little grey-green ball, wandering through space. I could make out, at most, only the subtlest detail on that little ball - and really it was virtually featureless. But the thought that that ball was four times the diameter of Earth gave me a rare, visceral sense of the scale of the Solar System. It can be hard to wrap your mind around the reality that the distance between Uranus and Saturn is actually greater than the distance between Saturn and the Sun. Now, at the eyepiece, it seemed obvious. I hadn't found Uranus before because I'd underestimated the size of the Solar System; I didn't imagine that a planet so big could look so small. It might seem like a drawback of manual mounts that it took me over 20 minutes to find Uranus - not to mention the many times I've searched for the planet and failed. Nothing could be further from the truth. When you do "star-hop" successfully with a simple mount, the sensation of actually finding what you're looking for is really special, and you don't get that with a go-to mount. You also start to genuinely learn the sky; I'd never thought about the constellation Cetus, for example, but now I know where it is, and I know that its third-brightest star is actually a triple-star system that I'd like to check out someday. That's not to say that star-hopping is always feasible or desirable, especially in the big city. But, as usual, you do give something up by opting for the convenience of modern technology. A last note on equipment: in recent days, I've ranked the Delos eyepieces, TEC 140, Orion 6x30 finder, DM-6, and Berlebach Uni tripod in comparison with other gear I've used. I've described them as the best I've seen in their class of equipment. Yet I haven't mentioned how well they all fit together. It really is seamless. The DM-6 holds the TEC 140 with perfect ease; there are no jitters, just buttery smooth movement even at high magnifications. The Uni tripod, while light, is an absolute rock, while the finder scope makes it a breeze to hop between stars. And the Delos eyepieces slotted in the TEC 140 provide a glorious view of just about everything. It's all very pricey, of course, but I really recommend this mix. The walk home was arduous. But, like William Herschel exactly 240 years ago, I'd found a new planet, and that made it easily worthwhile.
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We've had some wonderfully clear, autumnal nights over the past week, with Jupiter and Saturn riding high in the evening sky and the Moon waxing and waning nearby. I'm teaching what may be my favorite course at the moment - about the human history of nearby celestial bodies (what I call "neighboring worlds"), and a special highlight is taking my students out for a night with a telescope. I have now accumulated some very fine refractors, however, and I worried about how they'd fare after being handled by twenty students. To that end, I drew on my research funds to buy a William Optics Zenithstar 81. It's a beautiful little refractor, and I figured that it would be more than adequate to give my students an impressive view of the Moon. For their first assignment, they need to find a feature on the Moon and then write a history of how people have understood, imagined, explored, or planned to exploit that feature. A few things immediately struck me about the Zenithstar. First, it costs about a third as much as the TeleVue 85 I used to own - less than a third, when you consider it comes with its own mounting rings, dovetail, Bahtinov mask, and carrying case - despite giving up only four millimeters in aperture. Second, its build quality looks to be on par with the very best telescopes I own and have owned, with the possible exception of my TEC 140. Third, it seems to weigh less than the FS-60Q I once owned, and much less than the TV 85, and its sliding dew shield makes it much more compact than either telescope. It was really easy to carry the telescope to a darker corner of campus, and there set it up on my DM-4 mount and Berlebach Report tripod. Almost immediately, the Plossl eyepieces I'd decided to use provided beautifully crisp views of the nearly fully illuminated Moon. The students who had started to gather were predictably impressed. When we found we had a few minutes to spare at the end of the evening, I decided to try showing them Jupiter and Saturn. At about 56x, the planets were small, but beautifully sharp and clear. Many of my students were awestruck; they had a hard time believing that they could really see the major cloud belts of Jupiter and the rings of Saturn from downtown DC. Experiential learning is always special; it makes the otherwise abstract concepts we discuss in class come alive for my students, and it can provide lifelong memories. I for one was stunned by the performance of the little refractor. It is, by far, the most portable telescope I've owned, and when it comes to performance it really doesn't give up much to the TV 85. I loved my TV 85, but I would have a hard time recommending that telescope as a go-to instrument when the Zenithstar seems to provide so much more value for the cost. Last night conditions were even better, and now I resolved to head out with my biggest telescope: the TEC 140. The weight of the telescope, tripod, and mount means that I really can't haul everything to my favorite field. I targeted the little alcove next to a church that I've used over the past year, yet when I arrived as I was dismayed to find that the church had installed a new streetlight that completely ruled out observing there. I wandered about, dragging my heavy gear, until I decided to head down to a little amphitheater near the National Cathedral. There I found a perch that, if I moved around a bit, afforded me a view of Jupiter, Saturn, and the Moon through the canopies of nearby trees. When I swung the TEC to Saturn, I was mesmerized. This was only the second time I'd used the TEC, and the first time in good seeing. In those conditions, Saturn looked absolutely stunning, like a beautiful jewel set in a velvet background. Its many moons were brilliant and sharp, and the shadow of the planet on its rings gave me the rare sense that I was actually seeing a world in three dimensions (often, objects in the eyepiece look flat, and therefore two dimensional). Cloud details were obvious on the planet's yellow-white disk. Switching over to Jupiter provided an even more spectacular revelation. The TEC provided what may have been my best-ever view of the planet, with more cloud belts and zones than I could count, delicate, feathery structures within those belts and zones, and a perfectly obvious, brown "barge" - an elongated, oval cloud feature - near the planet's equator. There was a contrast and vibrance to the planet's colors that you just don't get with a smaller refractor, and all four Galilean moons were visible as clear disks, rather than points of light. Jupiter and Saturn soon wheeled behind the trees, so it was time for the waning gibbous Moon. Once again, I was dumbstruck. The Moon wasn't that far above the horizon, but at 163x there was just such a wealth of subtle, perfectly sharp detail, from jumbled crater peaks to winding rilles and delicate scarps. The terminator was perfectly positioned to throw mountain after mountain in sharp relief, and in exploring them I eventually lost track of time. Then a giant cricket jumped on my pants, I realized in shaking it off that it was past midnight, and I began packing up for the painful trek home.
The TEC 140, I have to say, is noticeably better than the APM 140 I've also raved about in these pages. I'm not sure it's worth the extra cost; certainly I could never have afforded the difference if I didn't use the telescope for my research and writing (which means I could draw from my research funds to buy it). I realize how lucky I am, and I hope I can keep using the telescope for a lifetime. It won't be that often, however, until I manage to own a backyard; as wonderful as the telescope may be, it's also hard to transport more than a few minutes from our home. Everybody approaches amateur astronomy in different ways, but for me - and many others - the most difficult thing about the hobby is that you always wonder, no matter how sublime the view: what would I see if I had different equipment? Usually "what would I see" means "what more would I see," and usually "different" means "just a bit better" - and that means that many amateur astronomers, at least at some point, embark on a long, frustrating, painfully expensive quest for new telescopes, new mounts, new tripods, new eyepieces . . . the list goes on. I've been on that path for quite a few years now. Yet when it comes to telescopes - or more specifically, to optical tube assemblies - I reached the end this spring. For a long time, I dreamed of someday - somehow - being able to own a truly world-class, medium-sized refractor. I long had my eye on the Telescope Engineering Company (TEC) 140: an American-made, oil-spaced triplet of uncompromising optical and mechanical quality that, while portable, easily outperformed much larger telescopes. I didn't think I'd be able to afford it for a very long time, but then I realized that although I'd slowly cobbled together a rather large collection of telescopes, I was really only using three of them (my EVScope, Takahashi FC-100, and APM 140). If I sold my unused telescopes and some other gear for the right price, I might just have the financial foundation I needed to pursue a used TEC 140. Precisely as those thoughts entered my mind, a TEC 140 ED in like-new condition popped up on the used market for a daunting but reasonable price. I took the plunge, and then went on a truly exhausting campaign to sell everything I could spare to recoup what I'd spent. Some of what I sold, I know I will miss for a long time. I ended up parting with my FS-60Q, TV-85, and APM-140, and each loss stings in a slightly different way. I've had unforgettable memories with the TV-85 and APM-140 in particular, but upgrading equipment is not for the sentimental. In the end I earned precisely as much money as I spent on the TEC 140, so my guilt was mostly assuaged when it arrived. Comparing it to the APM 140 was instructive and ended up highlighting the virtues of both telescopes. The TEC 140 is, first and foremost, slightly but meaningfully heaver and bulkier than the APM 140. Its focuser is more robust, its finish is of clearly higher quality, and its tube ringers are easier to manipulate. With that said, the APM's focuser is just as buttery smooth, and I actually find its sliding few shield a little easier to manipulate. It's not a tossup - the TEC 140 is clearly mechanically superior - but the APM holds up surprisingly well when you consider that it costs less than half as much (during sales, more like a third as much). Because the TEC 140 is that much bulkier than the APM 140 and uses a Losmandy dovetail that I didn't want to replace, I needed a new, sturdier mount. That's also because my AYO II mount had, after just a year, started to develop an unacceptable amount of slippage on one side. So, I scraped together what I could and purchased a DM-6 mount to match the DM-4 I purchased for my Takahashi. This, to be sure, is a beautiful piece of metal . . . but although mechanically superior to the AYO II (in my view), it's also very substantially heavier. The upshot is that my TEC 140 setup is a good deal less portable than my APM 140 setup had been. Because it's less portable, I can't take the TEC 140 to the field where I used to set up my APM. That field will be reserved for my FC-100DZ and EVScope from now on. On some level it feels like a minor loss - I had some wonderful times there with my APM - but I'm quite sure the FC-100 can pick up the slack. And I do now have the alcove, near the church by my home, that affords some fine views of the southern sky. The TEC-140 is also so heavy that I refuse to take it out unless seeing is above average. This morning, for the first time in a while, it was forecast to be. So there I was, huffing and puffing on the sidewalk at 4:00 AM, bound for the alcove and for a date with Jupiter and Saturn. Both planets have passed behind the Sun and are again high enough above the horizon to be worth a look. It was an exhausting walk, but setup was easy and quick as usual. When I turned to Jupiter, two things struck me. First, seeing was not nearly as good as advertised; that close to the southeastern horizon, it was average at best. Second, the color correction of the telescope was absolutely spot on. The older TEC 140 ED is supposed to be slightly better in longer (red) wavelengths than the newer TEC 140 FL, but slightly worse on shorter (blue) wavelengths, which should make the ED somewhat better for observing Mars and Jupiter, but somewhat worse for astrophotography. In any case, Jupiter's coloration was lovely, even if the planet's fine detail was often obscured by the turbulent atmosphere. Saturn, fortunately, was higher in the morning sky. Turning to the planet at 98x, with a 10mm Delos eyepiece installed, made for a genuine "wow" moment. Never have I seen more than a few of Saturn's moons, but now Enceladus, Dione, Titan, Tethys, and Rhea were all clearly visible. Subtle gray shading was easy to see on the planet's disk, as was a shadow just behind the rings (I love their orientation right now). The Cassini Division was plainly obvious but now around the entire ring system; unfortunately, seeing was just not good enough to see more. Once again, the color correction was sublime. After turning to some stars and observing them in and out of focus, it was clear to me that the telescope has - surprise, surprise - exceptional, beautifully corrected optics. Yet it struck me, as it did several months ago with the FC-100DZ, how much more seeing matters than optics when it comes to planetary observation. Did I see more detail this morning on Jupiter and Saturn with the TEC 140 than I would have with the APM 140? Maybe, just a little. But have I seen more detail with the APM 140 when the atmosphere cooperated? Absolutely. I'm looking forward to experiencing what the TEC 140 can do when the atmosphere truly is steady.
I suspect I will miss the portability of the APM 140, and wow that is a good telescope when you consider its cost relative to the TEC 140. Yet for me, it is important to know that the quality of my optics are not keeping me from seeing more planetary or lunar detail. With that in mind, I am very happy with my beautiful TEC. A distant goal, accomplished surprisingly soon! |
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