It was quite cold here last night, but I got a new eyepiece - an TeleVue Ethos 3.7 mm - and I was determined to use it. Unfortunately, the atmosphere was restless and the seeing poor to atrocious, so I was largely limited to low magnifications and wide field views. The TeleVue 85 was perfect for the task. Early in the night, the jewels of winter started rising over the horizon. I was on our illuminated observation deck with a three-inch telescope, and Orion was still climbing above the light-polluted murk of the eastern skyline, but still: I had a nice view of the Trapezium at around 66x. I even captured something of the view on my iPhone, though of course: much is lost in the translation. The Orion Nebula is something that never, ever gets old to me. The Pleiades, being higher in the night sky, looked spectacular, especially at very low magnifications (11x with my 55mm Plossl). Towards the end of my night, I finally used the Ethos on Rigel, and managed to clearly make out Rigel's companion, Rigel B (itself a double star, but that was beyond my telescope) at 162x. Not bad, considering the terrible seeing! The TV 85 is a masterpiece. As I've written before, I just don't understand how so much telescope fits in such a tiny package. At low or high magnifications, the view is consistently spectacular - and surprisingly bright.
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It's been rainy here lately. Inspired by similar lists I've read elsewhere, I decided to pass the time by evaluating some of the telescopes I've owned. I figure I've purchased, used, and sold enough telescopes to gain a sense of what's underrated, overrated, and properly rated. What follows is anything but a scientific list. It's just a sampling of impressions, with not so much as a star test thrown in. Anyway, I'd divide the telescopes I've owned into a few tiers: Excellent: Takahashi FC-100DC TeleVue 85 Takahashi Mewlon 180 These telescopes are a joy to use. They're beautifully built. They're solid, sturdy, surprisingly lightweight, and wonderful to look at. Every little detail exudes quality and works just as it should. And their optical quality is nearly flawless. I say "nearly" because none of these telescopes are at the very top - the absolute pinnacle - of their market (okay, maybe the Mewlon is). They're close, but no cigar. The TeleVue apparently does not quite focus every color equally for the viewer (though I've yet to see evidence of this). The FC-100DC might have a touch more false color than the other four-inch refractors manufactured by Takahashi, past or present (I've noticed none). Both telescopes compensate for these relative shortcomings by being compact and easy to mount: no small thing when you value portability as much as I do. The DC, for example, is about two pounds lighter and a little shorter than the LZ, Takahashi's newest four-inch refractor, and that's no laughing matter when you're trying to build the most portable and stable grab-and-go setup you can. The TeleVue and Takahashi refractors have interesting differences, which I've described elsewhere. The TV 85 seems a bit more user friendly and gives up very little to the Takahashi, despite its smaller aperture. What do I mean by user friendly? Well, I constantly have to turn compression rings to fit diagonals or eyepieces on the Takahashi, and when I do I often find myself unscrewing some module that really should stay firmly fastened. I had to extensively research and then purchase a separate gizmo so that I could detach my finder and thereby store my refractor in a relatively small case. I had to repeat that research to find a right-angle finder that would fit in the bracket Takahashi supplies, and that was after buying a straight-through Takahashi finder (the quality is spectacular, but I just can't crane my neck enough to make it worthwhile). I prefer red dot finders for bright objects; I haven't found one that fits onto the telescope. The focuser doesn't have a fine focus knob, and the draw tube isn't long enough to accommodate every eyepiece. Even figuring out how to attach the telescope to a mount was a minor struggle. These are the little, admittedly surmountable hurdles you get with a Takahashi that the TeleVue, built within the familiar ecosystem of western telescope accessories and practices, never throws my way. And yet I prefer using the Takahashi when I can; the view is just a bit brighter, and maybe - maybe - a touch sharper. I wouldn't swear by that last point. Either way, these telescopes are nearly perfect to me, and they're priced accordingly. Good, but not quite great: Skywatcher 100ED Celestron C8 These telescopes offer around 90% of the quality you get in the above tier, but at roughly a third of the cost. Only by comparing these telescopes directly to their pricier competition would you notice the difference. As usual in this hobby, it's the details. An extra hint of false color; a slightly softer view. Cheaper materials; a less comfortable focuser. More variation between individual telescopes. The little things that make all the difference. Still, I've had many a rewarding night with the 100ED. At its sale price around Christmas, this is the best value on the market today. And on the used market, you can often buy one in mint condition for $400 to $500 USD. Good for the money: Celestron C6 Celestron C90 Celestron Omni XLT refractor Skywatcher 127mm Mak Speaking of value: these telescopes are nearly as good as the ones in the above tier, each in their own distinct ways, but all cost around $400 or less. Of the lot, the C90 stands out. You can get this telescope for around $120 USD, with a (flimsy) tripod and a (perfectly respectable) eyepiece. Sell the eyepiece and you're down to $100 for a telescope that offers shockingly good views of anything that can stand high magnifications (it's an F12, so it doesn't do wide field). Add to that its small size and quick cool down for a Maksutov, and this may be the best starter telescope for someone on a budget. Put it this way: if you set up a TV 85 and a C90 next to each other, the Orion Nebula wouldn't look very different at first glance - yet the TV 85 is twenty times more expensive! Then there's the C6. These days it's three, maybe four times pricier than the C90, and it shows a good deal more. I've found that the best advertisement for a C8, however, is owning a C6. Looking through a C6, you immediately wonder what those extra two inches of aperture could do. Then you upgrade to the C8 and realize just how much bigger and bulkier it is. Depending on what you want, this is a value that rivals the best on the market. The Omni XLT is a strange (and, I gather, rarely-seen) beast. The tube itself looks and feels solid enough, but all the extras - the finder, the focuser, the diagonal - are child's toys. It's hard to shake the feeling that you've been had. But the optics are shockingly good: excellent for an achromatic refractor and on par with those of the Explore Scientific AR 102 (see below). The telescope is so cheap that you can replace the toy accessories it comes with and still get good value for your money. Thoroughly mediocre: Celestron Starhopper This was my first telescope. The optics were quite good; everything else was just terrible. Let's just say that the cheap plastic focuser and the cardboard tube did not stand the test of time. By today's standards, you didn't get good value for your money by buying this telescope. Disappointing: Celestron Edge HD 800 Explore Scientific AR 102 Skywatcher Flextube 12" Dobsonian Note the name of this tier. None of these telescopes are objectively bad - well, with one possible exception - but none failed to live up to my expectations for them. Buying them taught me a thing or two about what to look for in a telescope. Aperture and online reviews certainly aren't everything. The Edge was the biggest surprise. It has rave reviews wherever you look. And when I used my Edge for the first time - see below - I was delighted. Everything looked quite sharp, I concluded, given the seeing. Given the seeing. I used that excuse many times in the following year. It turns out, in cold weather the telescope refused to cool down, and in warm weather it dewed over almost immediately - once, faster than I could attach a dew shield! Even after an hour or so on one summer's night, the view of the Moon remained so soft that I was ashamed to show it to a curious onlooker (and she seemed thoroughly underwhelmed). What went wrong? I'm still scratching my head. Maybe I never did collimate it properly, but that seems implausible. Everything looked right on that front. Maybe it just needed a couple hours to acclimate - a couple hours I never had. The Skywatcher was simply too much telescope for me, then or now. It was so heavy and unwieldy that I barely used it, and when I did it refused to cool down. This is the telescope that taught me to avoid large apertures for urban stargazing. It didn't help that - again - the fit and finish disappointed. Rubber pieces came off the focuser when I tried to sell it! The buyer didn't flinch - I guess the asking price was that good - but I wasn't impressed. The biggest disappointment of all, however, turned out to be the AR 102. This is an impressive-looking telescope - in advertisements at least - and it has all the appearance of a can't-miss value. You get a quality finder scope and an excellent diagonal with a 4-inch refractor that promises very little false color, all for the price of a really good eyepiece. How can you go wrong? As always, the devil is in the details. The dew shield is flimsy. Screws are plastic. The label started to peel off the tube. And, worst of all: the focuser simply gave out one night and wouldn't work smoothly again. To their credit, Explore Scientific offered to fix it. But it took them so long to get back to me that I had already sold the telescope at a huge discount. What seemed like great value was anything but. I will say that the optical quality of the telescope was very good for an achromat. False color was, in general, noticeable but inoffensive on bright objects. The view of the Orion Nebula rivaled that of the 100ED. But the overall package was simply too good to be true. Gun to my head, I get to keep one telescope. Which do I choose?
It's an excruciatingly tough call between the TV 85 and the FC-100DC. In the end, the Takahashi would probably win me over with its larger aperture. But I would pine for the TeleVue. A short observing session tonight on the observation deck with the FC100-DC, in temperatures cold enough to become uncomfortable after a half hour or so. Despite the hazy conditions and nearly full moon, I tried to get a shot of the Pleiades, then high in the sky. For once taking a picture with my iPhone worked better than taking a video (the above shot of the Moon is a frame from a video). I'm not unhappy with the result, considering it's the product of a phone (and a very good telescope, granted). The Takahashi refractor showed some absolutely stunning details tonight on the fully illuminated parts of the Moon, especially around the around the Mare Tranquilitatis and Serenitatis with a Baader Hyperion zoom. There was the sense that you could keep on zooming in forever, with more and more detail popping into view. Even at around 200x, the view remained wonderfully bright; at times almost painfully so. I closed the short evening by hunting for Uranus. Alas: no luck tonight.
So I may have contracted a mild case of aperture fever. Not the first time, and likely not the last. I caught a glimpse of the Ring Nebula with my 100mm Takahashi recently, and part of me was impressed. With averted vision I could just make out a ghostly grey smoke ring - not bad, considering the bright urban sky. Yet the view made me wonder what it might look like through something bigger; viewing the moon made me wish for even higher magnifications and just a bit more light. I like my C8, but its optical quality isn't quite on par with that of my fine refractors. And while it cools down in 40 minutes or so if the weather is mild, that won't cut it in the winter. So, I bought a Takahashi Mewlon 180. It turned out that I had a lot more money squirreled away in my university accounts than I expected, and I can only spend it on research or research-related equipment. That meant telescopes, and the Mewlon, I felt, would fulfill all my needs. It squeezes a lot of aperture into a package that's almost as small as a Catadioptric, except it's a Dall-Kirkham reflector, which means it doesn't have a corrector at the front and therefore cools down quite quickly. It's also a Takahashi, and that all but guarantees excellent optical quality and superior craftsmanship. I was tempted to get the (even) pricier 210mm version, but after a lot of reading I decided on something just a bit smaller: something that would cool down even faster and be less sensitive to poor atmospheric seeing. When you take it out of the box(es), the Mewlon does not disappoint. It's the most beautiful telescope I've ever owned. It looks like a jet engine. It's a bit bigger than I expected - of course - but light and wonderfully well-balanced around its slender dovetail. I got a giant and excessively well-added carrying bag for it, which adds significantly to the hassle of lugging it to my observing sites but adds a little peace of mind, too. Within a week of the Mewlon's arrival, the sky was clear and the Moon a beautiful crescent. I carried both the Mewlon and my TV 85 to our observation deck. It was cold, and I used the TeleVue for about 35 minutes while the Mewlon cooled. Once again, the little telescope surprised me. It seems to defy the laws of physics by squeezing so much performance out of such a tiny package. Details on the Moon were simply stunning, and Saturn - despite being low on the horizon, and despite some very mediocre seeing - wasn't bad either. Two things were immediately obvious when I switched to the Mewlon: first, the view was brighter and I could use a lot more magnification, although the Moon was now lower on the horizon and the seeing was worse. Second, my little Berlebach Report tripod and VAMO Traveller mount just couldn't handle the Mewlon like they could the shorter - but slightly wider - C8. The view wobbled, badly. I've already ordered a sturdier tripod (another from Berlebach) and tripod (this time from Stellarvue). Still, I was delighted with the Mewlon. The Moon's terminator was just a bit more detailed, even at relatively low magnifications, than it had been through the TV 85. The view wasn't completely different at those magnifications - a testament to the much smaller TV 85 - but there was definitely more there, and it was crisper than it had been through the C8. At high magnifications - magnifications the TV 85 couldn't match - a new world started to emerge. I don't think the Mewlon had fully cooled down, however, despite the wait, and I wish I could have stayed out just a bit longer. Whenever the Moon is up, I try to take pictures using my iPhone 8. That's as close to astrophotography as I hope to get, at least for now. Although iPhone pictures inevitably have far less clarity, vibrance, and sharpness than views through the eyepiece, I am learning how to take better shots. I've given up on the gadgets that some telescope makers sell to mount the phone in front of the eyepiece; in my experience, the results are too often disappointing. Instead, I've learned to hold my hands more steadily - steadily enough to focus the phone on the object I'm observing. I've also learned to enhance the clarity and definition of the photos I take, and then slightly increase the settings for shadows, vibrance, and occasionally black point to better approximate what I'm seeing. My most important lesson, however, is to take videos of anything other than zoomed out views of the Moon. By taking videos, I can freeze on frames in which atmospheric seeing suddenly stabilizes. When I take a screenshot of those frames, the resulting picture is often much sharper than I get by just starting on picture mode. Some objects that are totally washed out otherwise - like Saturn - start to look like themselves when I take a video. I enjoy taking even the decidedly amateurish photos I can get with my iPhone. But at some point, I'd like to try my hand at sketching, like the nineteenth-century observers I've been reading and writing about lately. I doubt my results will equal theirs at first, but it will be fun to try.
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