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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We've enjoyed maybe the best stretch of clear nights with good seeing that I've experienced since moving to Washington, DC, and I was out nearly every night with a telescope in hand. Between work, childcare, and observing, I had no chance to update this blog - but now it's raining, and I have an hour (but just an hour) to relax. Roughly two weeks ago, I spotted a Takahashi FS-102 for sale on Astromart. Amateur astronomers will know that this is a four-inch refractor with a well-earned reputation for exceptional optics. It's been replaced by the Takahashi FC-100 series, and I already own a telescope in that line. But the FS-102, while much bulkier than my 100DC, does better at longer wavelengths. And in Mars-watching season, that's what I convinced myself I needed. Although the FS-102 was supposedly in pristine condition, when it arrived I was dismayed to discover that the lens cell was loose and the tube was covered - I mean covered - with scratches. Luckily, the owner was mortified when I informed him, and I received a (nearly) full refund. I now had some cash to spare, and at just that moment a new copy of Sky and Telescope arrived. A favorable review of the EVScope convinced me to give that telescope another chance (see a previous entry for my first impressions). Maybe the buggy version I owned before had unfairly soured me on the product? It did, after all, offer me a chance to observe nebulae and galaxies I would otherwise never have a chance to see from the city . . . . After it arrived, I bundled the telescope into a suitcase and rolled it along to my nearby park. After I turned it on, it just about instantly figured out where it was and slewed (quietly) to any object in the sky, like magic. Clearly, I'd been sold a glitchy version the first time around. This was more like it! And when I tapped on "enhanced vision" (I describe the technology in a previous entry), the effect was really satisfying. After a couple minutes gathering light on the Andromeda Galaxy, for example, dust lanes I'd previously spotted only with averted vision clearly snapped into focus. So, how good are the views? Well: although I managed to achieve fine focus, I think I'll need to collimate the telescope when I'm next out. Stars are not exactly pinpoints, as these images attest, and that's also caused by a tendency of the telescope to move too much while it's gathering and stacking images. There's more noise in the pictures than I'd prefer, and after getting used to my wonderful TeleVue eyepieces, the view through the EVScope's "eyepiece" is really cramped. It's like looking through a tunnel. More importantly: no, seeing an image through a grainy screen is just not at all the same as seeing it through an optical eyepiece. An optical telescope feels like an extension of the eye; not so the digital EVScope. But damn, it's cool to see galaxies shimmer into view on my iPhone screen. It's simply true that I can see things now that I never would have imagined seeing before, and isn't that what this is all about? I mean, the Triangulum Galaxy from an urban sky . . . are you kidding me? I'm still learning how to use this technology, and pictures I've seen online tell me there's plenty of room for improvement. Still, I've noticed that the images look much more spectacular in the app, while I'm in the field, than they do after I get home. Certainly they pale in comparison to even half-decent astrophotographs made with dedicated gear. Now does the technology always work seamlessly. Just a couple nights ago, I had to restart the telescope and reinstall the software before I could get the enhanced vision mode to work, and by then I'd already shivered outside for about 30 minutes. Some objects also look immeasurably better through my optical telescopes. The EVScope is just about useless for lunar and planetary views, and stars look like ugly blobs compared to the beautiful diamonds they resemble through my refractor. Yet what the EVScope does so well is find that sweet spot between visual observation and astrophotography, and it does so in an integrated package that's usually a pleasure to use. No, I never had the thrill of seeing something with my own eyes - the thrill I've described often in these pages - but I certainly did get a deep sense of pleasure when I glimpsed the Whirlpool Galaxy from the city. One virtue of the EVScope is its weight. If I stuff the EVScope into the suitcase I used for the APM - which, admittedly, does seem to mess with its collimation - then I can easily sling my Takahashi 60Q over my shoulder (and wedge its tripod in the suitcase). I've now used the 60Q twice, including once in the early morning, with the EVScope gathering Orion's light. I have to say: I was more than a little stunned by its quality. To my astonishment, the Moon through the 60Q really didn't look any dimmer than it does through the TV 85, and details were equally sharp. Here are three images I took of the Moon over the last week, with the 60Q, the FC-100DC, and the APM 140. A reminder: the 60Q has an aperture of about 2.5 inches; the 100DC of 4 inches, and the APM of 5.5 inches (these are big differences for refractors). The optical quality of each telescope is roughly similar, though I'd say the APM shows the most false color, and the 60Q the least. That's the 60Q on the left, and the APM on the right. The comparison isn't quite fair; seeing and transparency differed on each night - it was average when I used the APM, and decidedly better than average when I used the 60Q and 100DC - and while the smaller telescopes had fully cooled down when I took these images, the APM in my judgement had not. Still, it amazes me how slight the differences are. I have a new phone, by the way, with a much better camera, and I think it shows. These pictures were taken after the APM had fully acclimated, and I think it's fair to say that now the aperture difference is more easily visible. There's a deeper and more richly textured quality to these images than there is to the 60Q closeup above. Yet it always takes me aback to realize that, when telescopes are of similar quality, differences from night to night on bright objects - the Moon especially - owe more to atmospheric conditions than anything else, including aperture. It's different for dimmer objects. I can usually see at least five stars in the Trapezium using the APM, for example, but I've rarely if ever confidently spotted a fifth with any other refractor. Mars was full of detail when I observed it with the APM - wow that south polar cap looks bright and sharply defined right now - but I found that it, and every other bright object, was surrounded by a bright halo that night. This seems to be a common and very annoying optical effect in the skies of Washington, DC. On two nights with the 100DC, however, I had no such problem. Dark albedo markings were wonderfully detailed, and I spent easily an hour both nights just enjoying the view. It's a little sad to think that every night brings us a little farther from the red planet, but the view should dazzle for months to come. One last note. My first night out with the 100DC over these past two weeks was November 3rd. I suddenly resolved to stop doom scrolling and instead do something that distracted me. But what a sinking feeling I felt, walking bewildered to the field, with panicked screams - yes, screams - echoing around me. I walked out on the 4th, too, and the mood was lighter. Then, on the 7th, while playing with my kids in the very spot I usually set up my telescopes, came the good news: the networks had called it for Biden. I'll never forget the scenes of spontaneous joy on the streets: the bells ringing, cars honking, crowds cheering. We may be in for some very dark months this winter, but that was a moment I'll long remember. Opposition! What a word, for Mars observers. Earth is directly between Mars and the Sun in exactly one week, and it's in a part of Mars's orbit that takes it especially close to our planet. We won't get a view like this for 15 years or so, and we haven't had one like it since 2003. Technically, Mars was a little closer in 2018, but as I recall it didn't get very high above the horizon then for Northern Hemisphere observers, and a global dust storm - more likely when Mars is relatively close to the Sun - thoroughly spoiled the view. At the time, my telescopes showed only a fuzzy orange ball, with just the faintest hint of dark albedo features (and that was probably my imagination). I resolved then to be ready for 2020, and I certainly have been. This week, I explored the planet with my Takahashi FC-100DC and APM 140, and wow: what a view. I should begin by saying that I also observed Mars in single-digit (Celsius!) weather on the morning of September 22nd, but also the seeing was forecast to be average, the transparency of the atmosphere left much to be desired. There were odd halos around everything: street lamps, the Moon, and certainly Mars. I could only make out four stars in the Trapezium with the APM, and albedo features didn't pop on Mars as they can when the atmosphere is stable and clear. When the sky cleared again on October 4th, I decided to take my 4" Takahashi to the field. Mars rises early enough now for me to step out in the late evening - just before midnight - which typically allows me to sleep more restfully (albeit still for only four or so hours). This time, transparency was a whole lot better, but seeing was about the same: not terrible, but by no means good. Albedo features were stark and obvious on the planet, however, and I wished I'd taken a sketch pad. I was unhappy with the iPhone drawings I attempted to take on other nights, so I opted not to draw one of those - maybe a mistake, but it did give me more time to drink in the view at the eyepiece. The Moon had a hint of that "watery" look it can take on when the seeing is mediocre, but still: I had a nice long look at Mare Crisium at lunar sunset. Jupiter and Saturn had long since set, and I had a pang of sadness: I'm unlikely to observe them for a good long while. Mars will make up for it! Then, tonight, the seeing promised to be above average. I'd hoped to observe in the evening again, but unexpected clouds ruined that plan. By 3 AM the sky had cleared, and out I walked with my APM 140. To my alarm, Mars was already lower in the sky than I'd anticipated, and I feared it would be lower still by the time I arrived in my preferred observing site. I hadn't walked far when I noticed a dark alcove beside a church I frequent, and it occurred to me that it would afford a great view of the southern sky. So, I abandoned the field I normally visit for that alcove: a high risk gambit, since the field is a sure thing and it seemed entirely possible that there might be currents from nearby buildings to ruin this spot. Worse: the church is right next to the National Cathedral, and I worried: could security kick me from the grounds? But no, this time it all worked out. I found a nice corner to settle down, and when I turned the APM to Mars it was full of wonderful detail. The entire southern hemisphere of the planet seemed dark, relative to the rest, with spectacular, linear features that helped me realize how nineteenth-century observers could have imagined a network of canals on the planet. The south polar cap was remarkably bright and clearly defined, and I could just - just - make out the white clouds of the north polar hood on the limb of the planet. Mars reaches its closet approach to Earth next Tuesday at 10 AM EST: a scant 62,069,570 kilometers (by astronomical standards, a stone's throw). It was quite strange to see the planet so big and bright, entirely illuminated by the Sun. I felt it was almost too bright for the APM, strangely enough, at least at 217x (the highest magnification I felt I could use with a manual mount). Still: what an unforgettable view. The waning Moon was nearly at zenith, and in good seeing it also provided a spectacular view. Yet because I wanted to keep switching to Mars, I didn't adjust the height of the tripod - and that made for a very uncomfortable lunar viewing experience (painful, in fact, because of a worsening neck and back injury). I captured some quick pictures without being able to fully stabilize my old phone, and they actually turned out a bit better than I'd hoped. A testament to the capabilities of the APM in an accommodating atmosphere.
By next week we will be on the downswing of this year's opposition, and it already saddens me to think how long it will be before we have a similar view. What will the world look like then? With how quickly things seem to be changing - often, it appears, for the worse - it seems impossible to guess. With any luck, I'll still have this blog - and I'll still have a telescope as good as the APM 140. To say I was tired after my last morning out is an understatement. There's nothing like 16 straight hours of work and childcare after a three hour night's sleep. Yet when the forecast called for better-than-average seeing and transparency on another clear morning, I had to go out again. After all, it'll be a while before Mars looks this good. This time, however, I took my Takahashi FC-100 DC and my lightest tripod; I was still a little sore from hauling the APM. Conditions were just about the same this morning as they had been on the sixth, and that provided a nice opportunity to test how close the view through a good 4-inch refractor can get to that of a 5.5-inch (the APM). In a word (okay two words): pretty close! The Moon dazzled with detail, although I definitely saw finer features - especially those rilles - with the APM. Mars was wonderfully clear, with dark albedo features obvious but maybe a bit less dark than they had been through the APM, and the south polar ice cap much dimmer. Orion and the Trapezium were wonderful, but I could only clearly see four stars in the Trapezium - with a hint of the fifth, "F" star. You could drive a truck between Rigel A and B, but maybe a slightly smaller truck than you could with the APM. The Takahashi is just a fantastic telescope. I set out to observe Mars, and indeed I observed the planet for a good long time. Two years ago, during the last opposition, I dreamed of exactly the views I've had this year. Once again, I tried sketching the view on my phone, but it's become clear that I've reached the limit of what's possible with that technique. Next time, I'll bring sketchpad - but still, it's nice to know what I've seen. I found that the steady atmosphere easily permitted a magnification of around 250x, which is rare in these parts - and better than I enjoyed on the sixth. Although I spent a lot of time on Mars, I found I kept returning to the Moon. There's nothing like the gloriously detailed lunar views a fine refractor can reveal in good seeing. Features visible around the terminator were especially interesting tonight, with plenty of tiny craters glinting at local sunset, and some really interesting, rectilinear scarps (or so I decided; I'll have to look this up later).
So, another great morning - but it'll take me a few days to recover this time. The weather has been stormy over the past few weeks, but this morning the clouds cleared and the seeing promised to be good. I woke up at 2:45 AM and walked out the door by 3:20, hauling my APM 140. As I reached my local park, it dawned on me that conditions were essentially perfect. The sky was wonderfully transparent, the temperature was perfect, and there was a thin misting of dew on the ground. The rabbits and fireflies that used to give the park such a magical air, however, have largely disappeared (for now). It was a special morning for more than one reason. The Moon had just passed in front (occulted) Mars, and the two worlds were still right next to each other in the night sky. It was a stunning sight as I set up the APM. Then, when I wheeled the big telescope around to have a look at the Moon, I was just floored by the spectacular, razor-sharp detail. Rilles and craterlets snapped into view as I've never seen them, and I thought I could actually pick up gradations of color on a Moon that has always looked monochrome to me. It was easy to get lost in that view, but I had a job to do: observe Mars as it approaches opposition. Now, it's around five weeks away - hard to believe! - and wow does the planet look big and bright. The APM revealed it in spectacular detail, with Syrtis Major huge and dark on the planet's surface, arcing north from a south polar cap that now seems small (but bright), with Nodus Alcyonius obvious nearby. It was easily the best view of Mars I've had. By 4 AM the view softened a bit, as a turbulence entered our terrestrial atmosphere. I think I noticed a hint of the planet's rotation between 3:45 and 4:45 AM; Syrtis Major seemed just a bit offset from where it was when I set up. I knew my iPhone would never capture even a half-decent image of the view, and I kicked myself for not bringing a sketching pad. Still, I have an app called "Paper" on my phone, and I used that to quickly just down what I could easily see. An enormous amount of detail is missing, of course, including many subtle grays south of Syrtis Major. Yet I'm hopeful that I'll get better at this, and I could tell that it helped me observe more closely and carefully. By 4:30 AM or so, the highlights of the winter sky had climbed above the horizon. Of course, I had to have a look at Orion. To my surprise, six stars were visible in the Trapezium - a first for me, if memory serves. Through the APM, the nebula looked about as impressive near the light-polluted horizon as it does while near zenith with my Takahashi (or maybe even a little better). Rigel B was much easier to spot than I can remember, and the Pleiades were just spectacular. Venus, also rising in the east, was lost in atmospheric turbulence. But still, I observed its half-disk for a minute or so.
I've praised it before in this space, but wow - I cannot say enough about this APM refractor. There are times when I've fantasized about selling all my gear in exchange for an Astro-Physics refractor - something truly high-end. Yet I just can't see how the APM can be improved. I see less false color with the APM than I do with the Takahashi - even with the Takahashi's focal extender screwed in - and the detail, contrast, and color I can see on planets is just otherworldly (sorry). Bright deep space objects are a joy to observe, and the every last detail on the telescope - from the focuser to the dew shield - is a pleasure to use. Like my TV-85, there's something magical about this telescope. It's a true keeper. Also deserving of praise: TeleVue Delos eyepieces. They are, without doubt, the best I've used in terms of clarity, contrast, and comfort for my eye. Maybe I'll get another come Christmas. We're less than two months away from Mars reaching opposition, and the red planet is getting awfully bright in the morning sky. Its apparent size is getting pretty big, too, and there are - as yet - no signs of the planetary dust storm that made it so much harder to see details on the planet during its last opposition, in 2018. Now is the time to observe Mars, and with that in mind I dragged my APM 140 out of the apartment and down to the park at 3:30 this morning.
Wispy cirrus clouds were starting to advance from the west as I set up my telescope, and there was an odd haze in the air. Street lamps were surrounded with halos that took on an odd fractal pattern I'm not sure I've seen before. After I started observing, I noticed the same thing around Mars. Oh well! The planet was spectacular nonetheless. The clouds that constitute its south polar hood appear to have broken up as the southern hemisphere enters summer, and the ice cap - now clearly visible - seems quite small. I could plainly make out an an intricate latticework of dark albedo markings stretching up from the pole, covering maybe half the planet's surface. Tonight, the atmosphere allowed me to reach around 170x before the view got a little mushy, and at that magnification the planet is still quite small. Easily big enough, however, to discern a whole lot of detail. Venus had climbed fairly high above the horizon by around 4 AM, and wow did it look weird with the naked eye: squashed into a fat little triangle by those strange atmospheric conditions. It was hazy and painfully bright through the telescope, though still satisfying to see the planet, from our perspective halfway illuminated. I thought I could make out some detail in the planet's clouds around its terminator, near the equator, but seeing was bad enough to make me question that observation. The Pleiades, meanwhile, had also wheeled into view, and I had my first look at them with the APM. Naturally the view was brighter than I've had before, though I wished for a wide field eyepiece - I'd left my 55mm Plossl at home - and the seeing was bad enough to mar the view ever so slightly. Still an impressive sight, however. Once again, telescope, mount, and tripod all functioned exceptionally well. I'm impressed at how easily the lightweight AYO II handles the big refractor when everything is properly balanced. Bizarrely, the telescope handles more smoothly and easily than the Takahashi FC-100DC on the same mount - or maybe it just seems that way, since it takes a little more effort to use the smaller telescope's focuser (it's one-speed only). Certainly the APM is my favorite telescope to use, with the little TeleVue a close second (it would be first, but that big aperture is hard to resist). I was quite tired after I last published on this blog, but the night of the tenth was clear again - and again the seeing promised to be better than average. With a week of uninterrupted rain coming our way, I had to step out again. This time I decided to try our rooftop, which was been a little too crowded to feel safe lately.
I decided to see whether the APM 140 was portable enough to haul upstairs. To my astonishment, the telescope slipped easily into the Gitzo carrying bag that I've been using for my Vixen refractor. That sliding dew shield goes a long way. It also barely felt heavier, and it suddenly dawned on me that, because the APM can sit well on the same mount and tripod, it's actually just as portable as the Vixen. Imagine that: a nearly six-inch-wide, portable refractor! To my relief, the rooftop was relatively empty. I unpacked and set up the telescope in under five minutes, and of course the APM acclimates so fast that it was immediately ready to go. Jupiter was up first. To my delight, I'd tuned in on time for another shadow transit - my third in three weeks! To think I'd never seen one before. This time it was plainly obvious that it was Io's shadow on the Jovian clouds; I could clearly make out the moon as a tiny orange disk. How the mind soars to imagine its volcanoes belching sulfur into the radioactive torus swirling around Jupiter. I switched to Saturn, but the planet was just a bit lower in the sky than Jupiter, and the difference in seeing was plainly noticeable. Turning back to Jupiter, I was struck by how much better - I'm afraid there's no other word for it - the planet looks through the APM than it does through the Takahashi FC-100DC, even when the smaller telescope has its focal extender screwed in. The biggest difference, I find, is in the color. Jupiter's reds typically look a pale pink through the Takahashi, but they are clearly red - in the case of the Great Red Spot, a vivid crimson - through the APM. I also noticed that my Delos eyepieces offered a notably better view then the Naglers, for what it's worth. Both made by the same company, of course, but the Delos seemed to have just a bit more contrast, and they were definitely easier on the eye to use. I'm thinking now that I should swap my 9mm Nagler for a 10mm Delos, if I can do it while breaking close to even. As I admired Jupiter with the 6mm Delos screwed in, for a magnification of 163x, the seeing suddenly stabilized for around 20 seconds, and the planet suddenly snapped into crystal-clear focus. I was taken aback; I almost couldn't believe what I could make out. It was a textbook view of the planet - in that it could have literally appeared as a Hubble photograph in a textbook, held at arm's length, while squinting ever so slightly. The Great Red Spot and the swirling, complicated clouds surrounding it beautifully framed Io's shadow, and the details in the cloud belts were so richly textured . . . I was just astonished. When the seeing returned to normal, I could do nothing but pack up and leave. There are times in amateur, observational astronomy when you've had your fill and you need to step away to process it for a while. I packed up - again, in under five minutes - and stepped quietly downstairs, knowing I was sated for the week. A note on the APM. Earlier this year, I would not have believed such a telescope was possible - or at least, I would not have believed I would ever own one. Here is a refractor that, at 5.5 inches in aperture, excels at just about every object, but somehow manages to be grab-and-go portable. It weighs just a few pounds more than my much smaller Vixen - which is itself light for its aperture - and so a relatively light mount and tripod can comfortably handle it. I can carry it with ease. Its focal length is fast enough for wide-field views, but slow enough for magnificent planetary observation. It offers absolutely sharp, color-free views and first-class mechanical quality, at least on par with my Takahashi, but somehow costs just a hair more than that much smaller refractor - and about the same as the Vixen. Somehow, it cools down just about as fast as they do. It's true that my APM has what I gather is an unusually high strehl ratio - in other words, its optical quality is better than average - so my experience with this model might be unusually good. Even so, tonight's look at Jupiter - not exactly the easiest object to view - made me wonder why anyone would need or want anything more expensive at this aperture. My cup was full, and I can't imagine that any other portable telescope would have filled it further. In many cultures, in many times and places, bright comets were thought to herald - or perhaps cause, or confirm - disaster. It therefore seems almost absurdly fitting that, in this terrible summer of 2020, a naked-eye comet has appeared in our sky. I wrote earlier about failing to spot that comet - "NEOWISE" - in the morning, but it's rounded the Sun and is now visible in the evening - a much more convenient time for me to observe. This week I decided to make a concerted push to see it. I started with a pair of Nikon "Action Extreme" (ugh) 10x50 binoculars, on the 15th. After walking to our rooftop, I scanned the area south of the Big Dipper after sunset. The sky took longer to darken than I'd anticipated, but eventually, around 9:30 PM, I found NEOWISE. It's strange: this was my first comet sighting since Hale-Bopp way back in 1997, and it gave me a complex medley of emotions. On the one hand, it seemed a little underwhelming; Hale-Bopp and Hyakutake in 1996 had given me a wildly unrealistic frame of reference. I vividly remember seeing Hyakutake cover much of the sky, or Hale-Bopp's ion tail still visible at sunrise. By comparison, NEOWISE was a smudge - partly because it's dimmed since I should have been looking for it, a week ago. And on the other hand, what a thrill, nonetheless, to see a relatively bright comet; how exciting to receive such a vivid reminder that our Solar System is a restless and active place. On the 16th, I marched out again, this time with my Vixen ED115S. Several weeks ago, I tried to sell that refractor to afford my APM 140. I had a sale lined up, I thought, but the buyer kept asking for more discounts. Finally he asked for one more discount and posed a question that forced me to measure the telescope. When I did, I was struck by the beauty of the thing and declined to go lower - then sold some eyepieces instead. Thank goodness! The Vixen is just about a perfect telescope - it might actually be my favorite. As I've mentioned before, it's just the perfect size and weight for me, and perfectly well-balanced with its upgraded focuser. It provides just a bit more punch than the Takahashi can manage, and although it's heavier it's still very manageable. It's also, somehow, easier to use; the finder is in exactly the right place, the focuser is buttery smooth, and the handle makes it a snap to mount. Anyway, conditions could not have been worse on the 16th. Not only was it gusty, but the air was murky, thick with humidity, and thin clouds already covered much of the sky - with thicker clouds following in their wake. I scoured the horizon for that comet. Eventually I found it, peeking through high-altitude cirrus, further north than I'd remembered. Since it was already partly obscured, it looked only a bit brighter than it had using binoculars - but there it was, nonetheless, a bright little nucleus with a fan-shaped tail. Jupiter was rising, so I had a look before heading back downstairs. The seeing was terrible and haze covered the planet with a yellow veil, but still - the detail wasn't bad, considering. Then, miraculously, on the 18th conditions promised to be superb by DC standards: above-average seeing, according to ClearDarkSky, and above-average transparency, with not a cloud to be seen. I rumbled out of my building at 9:30 PM, with the APM in its giant suitcase. It soon dawned on me that I was more tired than I normally am; this was going to be a long, hard walk. After 15 minutes I was drenched with sweat and sore in a million places, but I'd made it to the park and covered myself with bug spray. I walked around and scouted out what I could see. Finally, I found a gap between houses that afforded me a good view of the comet, plainly visible with the naked eye but very close to the horizon. I had to set up in a far corner of the park to look through that gap, and the mosquitoes were worse there than they are in my normal spot. Still, I got a good view at last. I was struck by the brightness of the comet's nucleus relative to its tail - and struck, too, how little that tail seems to brighten with increases in aperture. The APM gave a clearly brighter view than the Vixen, let alone the binoculars, but the difference wasn't that great - not as great is it is when I view, say, the Ring Nebula. Still, the view was very satisfying - best with a 17.3mm Delos eyepiece at 57x, I decided. Higher magnifications did not seem to bring out any more detail in the nucleus, possibly because the comet had already neared the horizon. Using averted vision, I thought I could spot a hint of a halo surrounding the nucleus - more than the tail, that is - but that might have been my imagination. Either way, with the APM, a very fine comet; proportionally more elongated than Hale-Bopp, much shorter, of course, than Hyakutake, and far fainter but still aesthetically pleasing. When the comet got too low in the sky and the mosquitoes got too bad, I migrated back to my usual observing spot, where Jupiter and Saturn were rising to the east. When I had a look, however, I was shocked. The seeing was actually abysmal - some of my worst of the year. It was as though a southerly, high-altitude wind was rushing across my view, distorting and periodically compressing both planets. Jupiter still showed a good deal of detail in fleeting moments of greater stability, and the four Galilean moons all lined up made for a pretty sight.
But I was reminded again that you just can't count on ClearDarkSkies - or any tool based on our weather forecasts - to help you predict what the sky will be like. I enjoyed some of my best views this year - on May 31st, June 9th, and July 10th - when ClearDarkSkies predicted poor to average seeing, and some of my worst views when it predicted good seeing. In particular, seeing seems to differ in different areas of the sky, and you never know what those areas will be. On a mechanical front, I swapped my red dot finder for a right-angle finderscope on the APM, and that made a huge difference for the better. It's much easier to find things now with the big refractor. On the other hand, I also had a big more trouble using the telescope on my AYO II mount. I had to tighten the mount considerably to keep the telescope stable, which meant that it was harder to nudge along as I tried to keep up with the movement of the comet or planets. I might have been a little too impatient; maybe I should have worked harder to balance the telescope perfectly - but that balance does shift as I change eyepieces. At some point, I'll likely have to bite the bullet and buy a slightly sturdier (and heavier) mount. At least there's minimal wobbling after I do give a nudge. On another front, I suddenly realized last night that, after selling eyepieces to fund the APM, I suddenly have a dearth of high-magnitude eyepieces with a good field of view. When I can afford it, I'll need to invest in some more eyepieces. Or maybe I should sell more things I don't use? It never ends. To conclude, NEOWISE ultimately offered some memorable (if all too brief) views, and the refractors, as usual, acquitted themselves nicely. It's been quite a stretch of clear nights in these parts - as I wrote before, DC is a feast-or-famine city for amateur astronomers - and I've been determined to take full advantage. Last night, I hauled my APM 140 out the door for what I hoped would be an hour of deep space urban observing. As I embarked on the 15-minute walk to the park with, what, sixty pounds worth of equipment, I fretted about a fleet of clouds flitting by overhead. When I got to the park, however, the clouds had largely passed, and although I was drenched with sweat after all that hauling I was more or less ready to go. I was curious to see what the APM could do with no Moon in the sky. The first thing I noticed is that transparency wasn't great, but also that stars were pinpoints almost immediately. Although the difference in temperature from inside to outside wasn't great, I was still impressed that the telescope acclimated just about instantly. The Ring Nebula is almost comically easy to find these days, so I started with it. I could see a clear ring with no averted vision - always nice - but I can't say the view was much brighter then it had been a few days back, when the Moon was out. Still, a nice way to start the night. Next, I tried to track down some globular clusters in Scorpio, then rising out of the worst of the city's light pollution to the south. The double star Al Niyat was a gorgeous sight, but the globulars - M4 and M80 - were underwhelming. I abandoned the effort and switched to simply admiring some bright stars for a while, beginning with Antares. This, to my mind, is a principal difference between refractors and other kinds of telescopes. Stars look so much more beautiful - more natural - through refractors, in a way that's hard to explain. It's something, I think, about the size and color of the "disk." I decided to see if I couldn't track down the Whirlpool and Pinwheel galaxies around the Big Dipper. After spending about five minutes in futility, it suddenly dawned on me that the year was far enough along for Jupiter and Saturn to be rising in the evening sky. Sure enough, when I moved out of the shadow of a tree there they were, high enough already to observe. I didn't expect too much; they were still quite close to the horizon, after all. But when I turned to Jupiter I just about fell off my stool. There, on the limb of the planet, was the pitch-black shadow of a Galilean moon. And there, framed by Jupiter's North Equatorial Belt, was the moon: Europa, if I'm not mistaken. Suddenly the seeing stabilized, and wow: I've never seen so much detail and color on the planet. It was like viewing a Hubble image, at a little distance, while squinting ever so slightly. The Galilean moons were actual disks, not just points of light, though I couldn't see their color, let alone any albedo features on their surfaces. The seeing, I judged, was good but not great. But the telescope! What a thrill to observe the planet with a nearly six-inch refractor. When I turned to Saturn, I was nearly as impressed. The planet just had such a satisfying color through the big refractor: a creamy, buttery pale yellow, with mottled bands of grey cloud. Again, there was a space telescope - or maybe space probe - kind of feel to the image, a three-dimensionality and intricacy of detail that I've rarely seen before. I swung back to Jupiter. As I watched, Europa's shadow vanished in the limb of the planet, and the moon itself started to edge into black space. Then, the Great Red Spot rotated into view - and above it, on the northern hemisphere of the planet, an even darker mass of clouds. When the atmosphere really settled down, every cloud belt and zone was just absolutely full of delicate detail. What a thrill. I could have stayed for so much longer, but I knew it would be just four or five hours before my toddler woke up, and I had to get what little sleep I could salvage. What a memorable night! I've always wanted to be able to see real change on Jupiter - to observe the true dynamism of the inconstant planet. Finally, I had the chance to see the best the planet has to offer in real-time. I can't imagine any of my other telescopes would have shown me as much; the Takahashi might have come close, but not with so much color. I never imagined I'd be able to use such a big refractor before having a backyard. As I lugged the telescope back home, I couldn't stop thinking: it's so worth it for even one special hour with the giant planets. Rocking a fussy baby is a dangerous thing. The mind latches on to anything that can distract from the crying, and for me that means telescopes. Could I really use my Mewlon 180, I wondered lately? The telescope is beautiful, but it takes at least an hour to cool down - about as long as I often have to observe. And would I really feel comfortable collimating it in a park? Could I even haul it to a park in the handsome but bulky carrying case I bought for it? The answer to all these questions, I ultimately decided, was no. At the same time, I happened across a new telescope model: a 140mm refractor made by a German company, APM. At just under 20 pounds, this telescope is remarkably lightweight for a 5.5" refractor, and because it's a doublet - meaning it has two lenses - it cools downs quickly. Color correction is also excellent - maybe not quite as good as my Takahashi FC100, but on par with my TV 85 - and a sliding dew shield means the whole assembly is quite compact. Quality control is so good that the telescopes can ship with strehl reports, meaning you know exactly what effect unavoidable wavefront aberrations will have on image quality. The price, meanwhile, is unbeatable for a big apochromatic refractor. I couldn't help but think that the APM would work much better for me than my Mewlon, especially as I've gotten used to those pinpoint refractor stars. Once the idea was in my head, as usual, I couldn't shake it. I sold my Mewlon and a few eyepieces - including my cherished Ethos - then bought a rarely used, second-hand APM with an unusually high strehl of 0.958. To my surprise, the big telescope rides quite easily on my AYO II mount. I had been told that the mount can't quite handle refractors with similar apertures, such as the TEC 140. But if I balance the refractor just right, it does fine - provided I don't use a heavy eyepiece. Which, hey, I had to sell to buy the telescope anyway. Although I promised myself after June 9th that I'd only take a telescope out in the early morning if the seeing seemed above average, by July 1st I couldn't wait any longer. Both seeing and transparency promised to be below average on the morning of the 2nd, but the sky was clear and I wanted to test the refractor. I went to bed at 10:30 PM, woke up at 2:30 AM, and was out the door at 3:05. I'd bought a large soft case to haul the telescope and all my equipment except my mount, and it certainly made it much easier to walk the 15 or so minutes to my new favorite observing site. When I got there, however, my arm was nevertheless ready to fall off. This urban observing location is really special: screened by bushes in a large park that I have permission to use at night. As on the 9th, I was surrounded by rabbits and fireflies, and by 4 AM a cacophony of birds started calling all around me. The nearby trees are alive with noise - not bird calls, but animals moving through them. An army of squirrels? A flock of pterodactyls? Either way, it's a memorable experience being out there in the early morning. Turning to Mars, the image was clearly brighter than what I observed through the FC-100DC on June 9th, but also softer with a bit more light scatter. Nevertheless, that southern polar cap and some delicate dark albedo features were clearly visible. Switching to Jupiter and Saturn, it was clear that poor seeing and to a lesser extent transparency, not the optics of my telescope, would limit my morning views. Both planets had more color than they do through my Takahashi, and I could see a whole family of moons around Saturn - always a thrill. Even at high magnifications, the view remained bright - another step up over the Takahashi. Yet I couldn't really push past 100x and still see detail; the seeing was just not good enough. Still, the great red spot was as obvious as I've ever seen it. I wanted to have a look at the Ring Nebula to compare the light gathering capacity of the APM to my other refractors. With so much light pollution in the muggy sky, the nebula still seemed faint. But I could clearly make out a ring without using averted vision - a first for me. Then, at around 4:15 AM, I noticed a bright light on the eastern horizon. Was it a plane? Or could it be Venus? I had a look, and yes - there it was, a delicate golden crescent. I've never seen Venus look so beautiful; a mesmerizing sight that defied all my iPhone attempts to take a picture. Walking back was another huge chore, and when I returned I noticed that the wheels on my case already had some wear and tear. Still, I thought the telescope acquitted itself very well. The only false color I detected, I think, was a function of seeing. Stars were, of course, pinpoints. The view was noticeably brighter than it is through my Vixen - about as bright as it was through my dearly departed C8, I figured. Thermal acclimation was nearly instantaneous. The mount was sturdy, with vibrations at well under two seconds. This telescope is a keeper. On the evening of the 2nd, I realized that the sky would be clear again on the morning of the 3rd - except now the seeing and transparency promised to be average. Could I really function for a second day on four hours of interrupted sleep? Yes, I decided I could - and there I was again, in the park by 3:30 AM. This time I brought my Takahashi. I didn't have the energy to lug out my APM on so little sleep, and I wanted to compare the view through the FC-100DC with what I'd had with the APM. Mars was, once again, my first target. I had been a little disappointed with the view of Mars through the APM, although to be honest I would have been blown away had it not been for that magical morning on June 9th. Now, using the Takahashi again, I realized that the view on the 9th was a function of good seeing and good transparency - and a great little telescope, of course. The view on the morning of July 3rd was similar to what I'd had using the APM on the 2nd, albeit less bright and with a bit less scatter (possibly owing to better seeing). The south polar cap was easily visible, and some dark albedo features too - a fine view, but not comparable to what I saw on the 9th. When I turned the telescope south to Jupiter and Saturn, I was surprised: the seeing in that part of the sky was actually worse than it had been on the previous morning. Jupiter in particular was a hot mess, with nothing visible aside from the most obvious belts and zones. I could just make out the Cassini Division on Saturn, and I actually got some half-decent iPhone photos. Saturn photographs much better than the other planets largely because it's fainter. My phone washes out all detail on brilliant objects on a black background, so Jupiter especially almost always comes out as a bright white ball - except in those especially blurry moments, while taking a video, in which the picture just passes into or out of focus. In general, views of Jupiter and Saturn were worse using the Takahashi than they had been with the APM, but a lot of that comes down to a slight difference in seeing. I would say that, with the focal extender, the Takashi probably gives slightly sharper but less colorful and somewhat dimmer views. With that said, the difference in brightness on the planets was less than I expected; the Takahashi puts up a hell of a fight against any telescope, it seems.
Turning to the Ring Nebula, the picture was very different. In subpar transparency - the forecast lied - the nebula was only barely perceptible at all. I needed averted vision to see a ring, and then again - just barely. I guessed that the view with the APM was twice as bright, a gigantic difference, of course, when it comes to observing deep space objects. Once again, Venus loomed on the horizon when it was time for me to start thinking about packing. Once again, the view was glorious - and the iPhone washed out all details (ditto for Mars). Oh well - I took a shot anyway, and now it's on this website. Somehow, even terrible pictures help me remember the wonder. Dodging crowds of rabbits, I made my way home. The lack of sleep hurts, but I'll cherish these early morning memories. And I sure am happy to have another telescope in the fold. |
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