On November 16th, the sky was clear and, after a glorious sunset, atmospheric seeing promised to be mediocre but transparency was predicted to be superb. With no Moon in the sky, conditions were right to take the EVScope for another spin. I've now (separately) purchased the backpack that's sold with the EVScope; my rolling case, I suspect, my knock the telescope out of alignment. When I set it up this time, collimation was just about perfect. I made a couple tiny tweaks - again, this took seconds - and then rapidly achieved fine focus with the built-in Bahtinov mask. It was cold and I was exhausted, so I figured I would only take two ten-minute exposures of the Andromeda and Triangulum galaxies. Moments after the telescope slewed to Andromeda, I heard some rustling in the distance and noticed a dim orange glow, appearing and disappearing. Then the sounds of muttering wafted over on the breeze. It seemed I was sharing my park - and I had the disquieting feeling that I was being observed. After about eight minutes or so, I thought a third shadow joined the two in the distance, and then the rustling got closer. The conversation, it seemed, was definitely in Russian. Suddenly a flashlight turned on; there were three people, and they were walking directly towards me. I greeted them: "Hello? Hi!". At that, one of them exclaimed "oh my God!", and then all three of them darted to the side, behind a bush, and disappeared. The sounds receded into the distance. That was unsettling. Fortunately, after ten minutes the Andromeda exposure turned out nicely, considering the light pollution. Collimation and fine alignment really makes for much tighter stars and far better images, though I imagine things would be better still in superior seeing (and, of course, under a darker sky). Now it was on to Triangulum. It wasn't long ago that I managed to spot the galaxy with the FC-100DC, under darker skies some distance from DC. I noticed only a slight brightening of the sky, with averted vision, in what I could just perceive - or imagine - to be a spiral pattern. Clearly observing the galaxy now, from downtown, is a particular thrill. I don't know why, but Triangulum in particular has always captured my imagination. Maybe it's because it gets so little attention compared to the two giants of our Local Group of galaxies, or maybe because it's a face-on galaxy with distinctly knotted spiral arms . . . I'm not sure why, exactly. In any case, I find that the EVScope does a particularly good job on this galaxy (see above). And again, during the exposure I was in for a shock. With a loud thump and a lot of growing, a rabbit suddenly rushed right by the telescope, a fox in hot pursuit. The fox stopped short of my location with a snarl, then scampered - its little legs a blur - over a hill and behind a bush. Both fox and rabbit were no more than six feet from me. I couldn't wait to tell my four-year-old daughter in the morning. Anyway, after a few more minutes the Triangulum exposure was done to my satisfaction. I packed up the telescope, warmed my chilled fingers, and walked home. Suffice it to say, I've really started to enjoy the EVScope. A few days after my strange night with the EVScope, an ad appeared on AstroMart that forced me into hours of tortured thought (usually while attempting to get my one-year-old to sleep). Here was a Takahashi FC-100DZ, used only once and in pristine condition. As I've mentioned before, this year I've been tempted to swap my 100DC for a DZ. The DZ has better color correction and its optics might be marginally sharper, on average, though both improvements may be difficult to detect visually (I read many opinions, and they seem to differ). You can read a great breakdown of the relative merits of the four current FC-100 models here. I've resisted the urge to swap the DC for the DZ because, first, the hassle and expense seemed daunting, and second, the DC's weight is supposed to be lighter. The difference in weight, I concluded, outweighed (sorry) the marginal difference in optical quality. Yet the four-inch refractor is my most used telescope, and now I couldn't resist the urge to upgrade to maybe the finest refractor of this size ever made. So, I bought the DZ and sold my DC (along with some other stuff to make up the cost). I have to say, the comparison between DC and DZ surprised me in a few ways that aren't covered elsewhere. First and for my purposes most importantly, the weight difference between the two telescopes is scarcely noticeable. In the above pictures, you can see the DZ in a configuration for short-range, daytime viewing. However, to reach focus for astronomical viewing you must detach one of the couplings, and that makes the DZ noticeably lighter. It is then also more compact than the DZ when the sliding dew shield is tucked over the optical tube. Second, the most important couplings of the DZ do not screw apart but rather use thumbscrews and compression rings. You can also use that system to attach a diagonal, and I can't tell you what a difference it makes. I actually detest the Takahashi fetish for stacking screwable couplings in the visual back. The couplings, I've found, tend to stick together, and they're not wide enough to grip easily. It's easy to damage them (cosmetically) by applying too much pressure (I did as much to one of the DC's couplings). The new system brings the DZ in line with most other fine refractors, and it is just such a relief. Third, to balance the telescope - using just about any eyepiece - the clamshell tube holder must sit farther from the visual back than it does with the DC. This may seem like a very minor detail, but it provides more room for a red dot finder (RDF) just in front of the visual back. My Rigel QuikFinder RDF is now in a more comfortable position, and it's those little details that can make a real difference in the field. Fourth, the focuser is just a bit nice. Its knobs are metal - not plastic, as in the DC - and the feel is a bit smoother (though I did need to adjust the tension knob for my big Delos eyepieces). I sold Takahashi's two-speed focuser upgrade with the DC, and although I will no doubt miss the fine focus on the DZ, I didn't like how the two-speed add-on left some daylight around the gear housing. On the DZ, I'll stick with the stock focuser. That focuser, by the way, allows me to reach focus with all my eyepieces - something that was just out of reach for the DC. Finally, although the sliding dew shield is very smooth and easy to use, its tightening screw does leave a subtle mark on the optical tube that is noticeable when the dew shied is deployed. I wonder if the previous owner tightened the screw a bit too much, but I doubt it; I think this is just a natural consequence of the technology. It only matters if you're obsessive about the condition of your equipment - but Takahashi telescopes are so beautiful that they tend to bring out that obsession. Last night, and against my better judgement, I took out the DZ for the first time. I say "against my better judgement" because transparency was mediocre and seeing was poor. It's a recipe for disappointment to take out a new telescope in such conditions. I couldn't resist, but I did set up near the cathedral, closer to my house so I could hurry back if observing disappointed.
And did it? Well, a look at Mars did clearly reveal that the atmosphere would not be my friend tonight. And yet, I could plainly make out no fewer than three large dark albedo markings, along with that brilliant south polar icecap. Turning elsewhere, Rigel A and B were laughably easy to split in the poor seeing, and Orion was beautiful even before it emerged from the light pollution near the horizon. So could I make out an optical difference between the DC and DZ? Not after one night of poor seeing. Mars did seem a bit yellower than it does through the DC, and certainly I could detect absolutely no hint of false color in or out of focus. I'm excited to study the Moon, for example, on a really good night. Yet I don't expect a large or even a plainly noticeable difference. I bought the DZ primarily so I could be absolutely sure that the optical quality of my most-used telescope would never hold back my observations - and so that I would never wonder what something would look like with a slightly better telescope of the same design. It's a tiny thing, but after a while tiny things start to matter a whole lot in amateur astronomy.
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It was a cold, damp night when I stepped out with the EVscope and found a relatively mud-free corner to set up in my park. I decided to try my hand at collimating the telescope to see if that might tighten the stars in my pictures, and I hoped to decide, once and for all, whether to keep the telescope before my refund period ran out. To my surprise, the telescope was badly out of focus when I turned it on - so out of focus that its auto-alignment failed. Fortunately, it comes with a bahtinov mask cleverly built into the dew shield. Achieving rough focus, and then fine focus with the mask, takes a matter of seconds. With that done, the telescope immediately found alignment, and I got it to slew to Bellatrix, a fairly bright star in Orion. Now I turned the focuser knob until a dark cross appeared in front of the suddenly bloated star: the spider vanes holding up what would be a secondary mirror in most reflectors (but is a sensor in the EVScope). The cross was badly askew, which means that the telescope was poorly collimated. It took all of 30 seconds or so to fix the problem, and even less time to achieve fine focus again. And then, voila: the stars were more closely to dots - rather than smeared blobs - and the resolution of the telescope suddenly seemed higher. Funny how that works. I tried my hand at imaging a few objects: the Orion Nebula, of course, and the Flame Nebula, Bode's Galaxy, and the little galaxy NGC 1637. The latter was a bust: it's very small, and lost in the glow of light pollution to the south. An unavoidable problem for me is that the EVScope amplifies both the light of deep space objects and the light pollution in our DC skies. It's not a problem for brilliant objects like the Orion Nebula or the Andromeda Galaxy, but dim, diffuse objects are another story. I also didn't take exposures longer than five minutes. It's one thing to gawk at the Moon or Mars for that long - or much longer - but another thing to sit silently in the cold, waiting. But was it ever cool to see the spiral arms of Bode's Galaxy, slowly brightening on my screen as the minutes and seconds ticked by. Here were photons 12 million years old, from a galaxy nearly the size of our own, somehow visible in an urban sky. The view was quite sharp, I thought, and the telescope performed perfectly, immediately slewing to whatever I asked it to find.
Do I prefer my optical telescopes? Yes, for most objects I do, but it's simply true that the EVScope shows me hundreds of nebulae and galaxies that I never imagined seeing from the city, and reveals glorious detail in wonders I thought I already knew well. It's a keeper. Now if only I could get a lightweight, go-to mount for my refractors . . . . 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. |
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