Our indefatigable news media seems to have transformed every full Moon into a show-stopping event. It's always a super blue wolf harvest something or other. To be fair, the hype stirs up a good deal of popular interest in our neighboring world, and to my mind that can only be a good thing. Of course, amateur astronomers know that because a full Moon has no shadows, it can be unsatisfying to observe with a telescope. The craters, mountains, and rilles that are otherwise so obvious seem washed out in a sea of milky-white brilliance. Still, the trees in my backyard have not yet unfurled their budding leaves, and pockets of the night sky remain visible just steps from my kitchen. The other night, I couldn't resist setting up my Takahashi TSA 120 as the full Moon moved through a gap in the bare branches. Atmospheric transparency and seeing were both about average - at least in theory. In practice, conditions seemed to shift by the minute. Occasionally a watercolor softness blurred the Moon, but then it snapped into focus for many seconds at a time. For amateur astronomers, our atmosphere truly is a fickle antagonist. Using my iPhone, I don't believe I managed to get a picture of the Moon in its clearest moments. Still, just look at those mountains outlined in sharp relief on the limb of the Moon. Rarely have I managed to get such an obvious look at them. Crater rays, meanwhile, are actually a lunar feature that becomes obvious only with the Moon fully illuminated. It was wonderful to follow their tendrils across the the Moon's silvery regolith. As for the telescope, what is there to say? Among apochromatic refractors, the TSA 120 is about as perfect as it gets. Nitpicking comes easy to me, but in this case there are no nits to pick. Actually, the telescope's size reminds me a little of the Vixen ED115S that I used to own (with its oversized Moonlite focuser). I thought the Vixen was the perfect size for a refractor, but the TSA might be even better. It actually feels a bit lighter and more compact, but the aperture is just a bit bigger. A five-inch refractor is a really ideal: it edges out the performance of a four-inch, but doesn't need a much bigger mount and tripod (which can be necessary with just half an inch of extra aperture). I recently acquired a DSV3 mount from Desert Sky Astro. This is a manual mount that isn't too heavy and seems extremely well made. It includes both slow-motion controls and a handy "quick balancing system" that allows you to easily compensate for the weight of different eyepieces. With just a flick of the wrist, the telescope stays balanced. It's a clever little feature that, I discovered last night, makes observing just that much easier.
Readers will know that I'm a manual mount aficionado. When you don't have much time to observe, or if you want to avoid all hassle in a public park, there's simply nothing better. So far the DSV3 seems like the best medium mount I've used, and I've tried just about all of them. It's at least as well made as the best mounts on the market, and it includes features that its competitors simply don't offer. For the TSA 120, it truly is just about perfect. After I'd observed for no more than 30 minutes, the Moon rolled behind my building, and with fingers numb from cold I packed up my telescope. As I've mentioned here before, it's hard to think of a better use of time than exploring another world from the comfort of your backyard.
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Electronically Assisted Astronomy (EAA) has been around for a while. Not long ago, you'd get into it by buying a camera, attaching it to your eyepiece, hooking it to a monitor, and then watching as it combined - or "stacked" - images of nebulae or galaxies. Before long, the image on the monitor would take on the recognizable shape and color of a deep space object that, viewed unaided through the eyepiece, appeared as little more than a barely-perceptible smudge. Gone was the romance of peering at the space beside that smudge (using averted vision) and imagining, say, the combined light of 250 billion stars. But, if we're being honest, the magic got a little stale when squinting at one equally dim blob after another. EAA offered no substitute for looking through a big Dobsonian under a dark sky. Its images paled in comparison to those that could be taken with a complicated astrophotography rig. But for those of us stuck in the city and unwilling or unable to try serious astrophotography, EAA let us see what otherwise seemed out of reach: the universe beyond our solar system. A few years ago, two startups - Unistellar and Vaonis - took the obvious next step by debuting an integrated telescope, go-to mount, tripod, and stacking camera. Both the EVScope (Unistellar) and Stellina (Vaonis) were small, portable, and remarkably easy to use compared to any telescope on the market. Both were priced far beyond the cost of their parts; it is, after all, expensive to sell a niche product as a brand-new company. Still, despite the exorbitant cost - I shudder to think of what I paid for my EVScopes - enough people bought the new "smart" telescopes that both companies seem to have prospered. When both the EVScope and Stellina succeeded, it was clear that amateur astronomy would never be quite the same. The technology would keep improving, and bigger, more established companies would get in the game. A maturing market, meanwhile, would permit economies of scale. Those who waited on getting the first-generation EVScope or Stellina reasoned - correctly - that prices would soon collapse. Anyway, I bought my EVScope 2 for about $5,000. Recently, Vaonis released its next-generation Vespera II for about $1,600. The Vespera II is much more compact, it has a more sensitive sensor, it focuses itself (unlike the EVScope), and it's built around an apochromatic refractor that, in theory, should yield sharper images. I sold my EVScope and used the funds to purchase the new Vespera - and a few other things, because wow that price difference is huge. These are two approximately 10-minute exposures of the Orion Nebula. Atmospheric transparency and seeing were about average - maybe a little worse than average - while I took the picture on the left. Both conditions were definitely above average while I captured the shot on the right. Believe it or not, Orion was also much higher in the night sky while I took the picture on the right than when I took the image on the left. Of course, I took the picture on the left with the $1590 Vespera II and its $229 light pollution filter, while I took the image on the right with the EVScope 2, which is now on sale for $4,409. The Vespera focuses itself, but I'd carefully collimated the EVScope before using. I expected a difference in performance, sure, but the magnitude of that difference still astonished me. Actually, these pictures do not reveal the biggest distinction between the two images. Because of the Vespera's shorter focal length and more sensitive sensor, its images capture far more of the night sky. In fact, its new "CovalENS" feature allows for the integration of multiple stacked images of adjacent corners of the night sky, which should enable sweeping mosaics of, say, the entire Andromeda Galaxy. And I should emphasize again that the Vespera is much smaller and more portable than the EVScope. Admittedly, the EVScope comes with a tripod, while the Vespera does not (though again, the Unistellar backpack is much pricier than the one offered by Vespera). And the EVScope does have other advantages over the Vespera. It has an eyepiece, so if you want to use it like a regular telescope, you can. As I've often reported in these pages, the view through the EVScope eyepiece looks better than the pictures, though I suspect this is partly because the image is smaller. Magnifying the image on the bigger screen of a phone - let alone an iPad or laptop - reveals its imperfections. The Vespera also looks like something built by Apple, seemingly to appeal to buyers who see Apple as the gold standard for sophisticated, problem-free technology. It's a problem. The telescope's sleek surface is slippery and difficult to handle, especially in the cold. Screwing it into or out of a tripod is frightening. It wobbles dangerously and threatens to plummet to the ground (not a problem with the EVScope). It's also easy to accidentally open the Vespera, since there's nothing to lock the optical tube in place until needed, and the power button is far too easy to activate while holding the telescope. The button shines with a bright blue light when it's on. That will be familiar to users of common consumer products, but any amateur astronomer will tell you that a bright blue light is exactly what you don't want as your eyes adjust to the dark. Unlike the EVScope and other competitors now on the market, in important ways the Vespera prioritizes form over function. There's more. Whereas the EVScope has no problem with nearby street lights, the Vespera's lack of a dew shield allows those lights to easily create distortions in the image. Horizontal lines at the top corner of my images, I was told, are the product of a nearby (but not particularly bright) light. The lack of a dew shield is also, of course, a ticket to frustration in cold or humid climates (Washington, DC can be both). Vespera sells a screw-in Hygrometer Sensor - for an extra $119.
Then there's the lack of citizen science. Unlike Unistellar, Vespera has no fancy partnerships with the big guns in space science. If you want to join my friends at the SETI Institute in searching for exoplanets, you're out of luck. And if you want to help NASA track its spacecraft, stick to the EVScope. The biggest problem with the Vespera II, however, is battery life. The EVScope 2 can keep imaging for up to nine hours, and other Unistellar models do even better. By contrast, the Vespera has four hours of battery life - supposedly. I found that its battery consistently dropped down to 85% capacity after I had set it up, which takes over five minutes (setup was much quicker with the EVScope 2). In subzero temperatures, I suspect I could squeeze about three hours out of the telescope. Storage capacity is also much lower in the Vespera II, compared to the EVScope 2, but to me that doesn't matter; I always move good pictures to my phone's photo album. So do the many little shortcomings of the Vespera II, relative to the EVScope 2, overwhelm the advantages of its sharper, bigger, more colorful images, its autofocusing, and its more portable size and weight? The answer is: no, not even close. At present I think the new Vespera is simply a much more capable telescope, and again: it's sold at a fraction of the cost. In fact, I now fear for the future of Unistellar. The likes of Celestron and ZWO are offering telescopes that target both the high and low ends of the smart telescope market. I suspect that, if Unistellar stays in business, it will owe a lot to the connections its founders wisely made with SETI and NASA. I should say that I've reached my conclusions primarily by observing the Orion Nebulae. Planetary images, I suspect, are better with the EVScope 2 than the Vespera II, owing in part to the former's greater focal length and aperture. But that's really not why I'd want to use EAA. Even my C90, for example, gives a vastly better view of Jupiter than the EVScope could provide at twenty times the cost. Of course, as I've often described in these pages, all smart telescopes have the same shortcoming. To use them you wait around and stare at a screen. There's still something different - something special - about looking through a glass eyepiece instead, at age-old light at it shimmers through our roiling atmosphere. |
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