December 27, 2019
Every Christmas, I head to Winnipeg with my family to visit my in-laws. It is painfully, mind-numbingly cold, and of course I miss my telescopes back home. Yet I've managed to cobble together some equipment that lets me scratch my astronomy even while far from home.
This Christmas, I bought an Explore Scientific Twilight I mount to store in Winnipeg. This is my second time purchasing that mount - I sold my first purchase to help finance my VAMO traveller mount - and I again find myself both impressed and disappointed. The mechanics are, on the whole, quite good. It looks great! But quality control at Explore Scientific seems spotty at best. Twilight mounts have magnets that hold an allen key you use to adjust the inclination of the mount head. Both mounts I purchased had hanging magnets, only partly attached with glue. This new mount is smoother than the old one, but again the slow motion knobs just don't stay tight for long, which means that there's give in the slow motion controls. Not a big deal, but I've found that this is the biggest difference between premium products and that next step down: you know just what you're getting when you pay top dollar.
In any case, the mount makes a good pairing with the C90 I already had in Winnipeg, but not a great one. The C90 is almost comically over-mounted. I also managed to buy a C6 for Winnipeg this time around - they're bizarrely cheap right now - but it hasn't arrived yet. I felt its absence keenly when I tried to use the C90 to observe the crescent Moon on a cold (-20° C, or -4° F) morning soon after arriving in Winnipeg. Maksutov telescopes take a notoriously long time to reach thermal equilibrium - it's why I don't have one in DC, where I have to observe soon after setting up - and the C90 is certainly no exception. After 30 minutes the C90 hadn't come close to reaching thermal equilibrium, and the view was a blurry disappointment. The C6 should cool down a little faster, and then provide better views.
Roughly a week later, on a clear and positively balmy (around -8° C, or around 17° F) Winnipeg night, I stepped out after letting my C90 cool for around 45 minutes. ClearDarkSky told me that seeing would be mediocre at best, but in fact I found it remarkably good. The stars scarcely twinkled, and in fact for many minutes I enjoyed just looking up at the night sky with naked eye. When I turned to my telescope, I found the standard C90 finder to be every bit as bad as I remembered. It's literally unusable, and unfortunately the long focal length of the C90 makes it hard to use the telescope at low magnifications as its own finder. In the cold, I eventually found the Orion Nebula, and the view surprised me: not quite as good as what I see through my TV85, but not too far off. Through Winnipeg's dimmer light pollution, the nebula seemed about as bright as it does with the refractor back home.
After a little while I managed to see Rigel, too, and there was Rigel B, plain as day. With bright stars the difference between refractor and Maksutov telescopes is a little more obvious: though the C90 does a good job, stars are just a bit more colorful and a good deal sharper through the TeleVue or Takahashi. I gave up trying to observe Betelgeuse by telescope but did linger on it with naked eye. The giant star has been dimming of late - in fact I noticed that a couple weeks ago - and some think it may soon explode in a supernova brighter, from Earth, than the full Moon. In any case before long my fingers started to go numb, so I picked up my whole setup and simply carried it inside, in one go.
All in all, a good night. The C6 will likely reveal far more, and I look forward to using it here in Winnipeg.
May 19, 2017
Astronomy equipment! How my wife swoons when I talk about it. Okay, that's a lie . . . but she does roll her eyes. And warns me not to get much more. So of course I have to write about what I've been up to since February, even if I doubt anyone else will read this.
Let me start at the beginning. Come February or so I had two achromatic refractors, with designs on sending one to my summer hideout in Winnipeg. After some more thinking, I realized that was impractical. Sending my Celestron XLT across the border would cost more than buying a brand new telescope, and besides: I desperately needed new eyepieces that would do justice to my 8" Edge (hereafter referred to as a C8).
I ended up selling the XLT and using my winnings to buy an Explore Scientific 8.8 mm 82° eyepiece and yet another telescope: a C90. The C90 is a neat little Maksutov-Cassegrain that has good optics and is portable enough to take on a plane. The eyepiece is one of the least expensive premium pieces you can get, but it's an awfully big step up over the cheap Plössl designs I'd been using for high magnifications. I also received a Celestron Trailseeker tripod from a friend. In March, I somehow managed to take apart the tripod (not without almost breaking it) and carry both telescope and tripod in a backpack on a flight to Winnipeg.
My daughter has been a restless sleeper as of late. In March, it was all but impossible to leave our Washington apartment at night without waking her up. It was a different story in Winnipeg, where we stay in a bigger house. The sky cleared up for our last nights there, which gave me a chance to observe Jupiter for the first time since the summer of last year. Winnipeg is bitterly cold in March, so I left the C90 outside for about an hour to cool down. At last, I wrapped myself in a couple sweaters and a thick coat, and stepped outside.
Within seconds, I hit on a depressing realization: the Trailseeker mount and tripod, while light, are awful for observing at moderate to high magnitudes. I weighed them down with a heavy backpack, but still: my view shook and lurched wildly when I tried to make minor adjustments. I had an equally frustrating time trying to use the little finderscope on the C90. It's too small to look through comfortably and too close to the telescope.
At least the most important part of my setup - the C90 itself - seems rock solid. In rare moments of wobble-free clarity, my view of Jupiter was among the best I'd had to that point. The north and south equatorial belts were, of course, easily visible, as were the tropical and equatorial zones. I also managed to glimpse a hint of the irreducible complexity of Jupiter's polar regions. And I spotted all four of the Galilean moons, lined up to one side of the planet (if memory serves).
When I stepped inside, a thick layer of frost coated my C90. Sadly, the ice revealed that I had smudged the corrector with finger while fumbling with the dust cover, which rattles loose at the slightest provocation. I'll have to clean that in the summer. For now, the C90 seems like a real winner. I'll miss my XLT, but the C90 has almost the same aperture and a longer focal length. It seems at least equally capable on planets. And of course, I can't imagine how I would have traveled with the bigger refractor.
Just before viewing Jupiter in March, I attended a workshop at the Smithsonian Museum of Air and Space, where I met Scott Bolton, the Principal Investigator of the Juno mission now orbiting the giant planet. Scott shared some of Juno's latest discoveries, including those incredible images of the planet's poles. Seeing Jupiter after chatting with Scott was a pretty surreal experience. Isn't it crazy to think that people like you and me can lead teams that send machines to distant, alien worlds?
After I returned to warmer Washington and my daughter started sleeping a bit better, I took my C8 outside for a second time. I soon realized, to my great disappointment, that my mounts just couldn't handle the bigger telescope. The Twilight I mount that seemed overall adequate when I first used the C8 turned out to be unbearably wobbly when I tried it again.
The NexStar mount and tripod that I had ultimately planned to use with the telescope was equally shaky when I ran it through its paces inside. When I bought my C8, I didn't expect that the Edge variant would be heavier than the regular old C8 that the NexStar is designed to handle. And in any case, I usually observe amid some bushes in a labyrinthine garden that's only 40 or so feet away from a sidewalk in an apartment complex. I am, apparently, the stargazing version of Sean Spicer. Did I really want to use a noisy electronic mount with a big red light under such circumstances? And did I want to spend precious time fiddling with electronics when I usually have no more than an hour or so to observe?
I decided to bite the bullet and sell both the NexStar setup and the nifty StarSense camera I bought for it. This was, of course, a huge hassle, but after a whole lot of advertising and fretting and negotiating and packing I managed to sell everything for a pretty good price. Now I had to find a tripod and mount that would be light enough to easily carry to my observing site and sturdy enough to handle my C8 with minimal vibrations. I didn't want electronics but I did want something that I could use to easily track planets, which move very quickly across the night sky.
I quickly found that my best options for easy planet tracking weighed around 30 pounds, which just isn't practical to carry along with my other gear. The heavier and more awkward this stuff gets, the less I'm inclined to use it. Both the options I initially had in mind were also equatorial setups, which would have taken too much time to set up (at least before I got used to it).
After asking the good folks at Cloudy Nights for some advice, I settled on a Universal Astronomics (UA) Macrostar Deluxe mount and a medium tripod. UA is a one person company run by a craftsman who fashions some of the best alt-azimuth mounts and tripods available on the market. The setup I bought from him is actually overkill for my telescope: it should be study enough to handle something much bigger, which will give me the option of upgrading in the (distant) future. Yet the mount and tripod only weigh around 20 pounds combined, which isn't much more than my Twilight I. When it comes to grab-and-go mounts and tripods, I think there's a tipping point somewhere between 20 and 30 pounds. Somehow, 30 pounds just seems unmanageable.
Once I bought my new setup - one of the last that will ever be manufactured by UA, it turns out - I also purchased an AstroTech diagonal and a Blue Fireball visual back with the money I had left. An observing instrument is much more than just an optical tube assembly (OTA). Light enters through the OTA, sure, but it then passes through a visual back, bounces off a diagonal, and pours into an eyepiece before it reaches the eye. You can have the best OTA in the world, but you won't experience its full quality without an equally good diagonal and eyepiece. A flimsy tripod and mount has much the same effect, since it's hard to see subtle details when the view is shaking.
Anyway, it's taken me about a year, but I think that my main observing instrument finally has no major weaknesses. Nothing is absolutely top of the line, but it's awfully good for my purposes.
I've now used my complete setup two times, on warm nights when my C8 reaches thermal equilibrium relatively quickly (though it's never fast). Both times, I concentrated on Jupiter. The UA was rock solid and rolled easily to my target, although I quickly decided that I should have bought the optional handle (it's now on its way). It was hard to sell my fancy electronics, but I now know that I made the right choice. I learned from keeping a huge and increasingly dusty dobsonian in a little apartment that the best gear is the gear you know you'll use.
Anyway, on the first night I didn't bother to check Stellarium before walking outside, and I was startled to see volcanic Io nearing the limb of the giant planet. I can't describe how cool it is to see Io as an orange point of light, and to know that the orange comes from volcanic activity. Seriously, how awesome is that? This is a little world nearly 700 million kilometers away, and I can get a sense of its surface.
I started at 145x (using my 14 mm eyepiece) and then moved up to 231x with the 8.8 mm. I watched as Io passed into the limb. To my surprise, I couldn't spot a shadow. Was the seeing that bad? Is my eyesight that poor? Well, the seeing wasn't great, but my eyesight is just fine. Perhaps the real issue was and remains my skill as an observer. This may soon painfully obvious, but if there's one thing I've truly come to appreciate as I've gotten back into amateur astronomy over the last two years, it's the skill of being able to see subtle detail on shimmering objects. It takes training, it takes preparation, and perhaps most of all: it takes patience. You need a focused mind and a surprising amount of strength to keep yourself still at awkward angles.
Well, I'm improving. On my second night out, Jupiter was a little higher in the sky and the seeing was a bit better (although the sky was less transparent). More importantly, I really tried to concentrate on what I was seeing. I stayed still, blocked the nearby streetlights (with a copy of Sky and Telescope, no less!), and struggled to tease out subtle details when (Earth's) atmosphere settled down and the view stopped shimmering so much. I also tried my first astronomy sketch . . . which is abysmal, as you can see. Still: I spotted some real detail in the equatorial belts, and a hint of festoons in moments of good seeing. I even glimpsed the north and south temperate belts. Maybe I'm getting the hang of this!
My C8 really is a joy to handle, but on Jupiter I did wish for just a bit more contrast. The cloud belts don't quite pop like I imagine they would through an apochromatic refractor. The sharpness and brightness of the view is really nice, and you can't argue with the portability of a Schmidt-Cassegrain. It may just be my favorite kind of telescope. But of course: once you see something amazing in this hobby, you start dreaming about the next step. With that said, I think I can take the next few steps simply by becoming a more skilled observer.
That about does it for now. I'm really happy with the changes I've made. I now have a perfectly capable little telescope for my summer stays in Winnipeg, and two great telescopes with very different capabilities and a whole lot of excellent gear in Washington. I'd love to have a better mount and tripod in Winnipeg, but overall I can't complain.