Sunday, March 20, 2011

 

Unk’s Faux Unitron


No, the restored Charity Hope Valentine didn't get a swing at the Messier Marathon, muchachos. It was unrelievedly cloudy this past Saturday after a Friday that saw massive tornado-bearing storms roll across the Gulf Coast. Charity will eventually get to show her mettle with as many Messiers as Unk can stay up late enough to catch, but this time I want to tell you about a different telescope and a simpler sort of astronomy: unplugged amateur astronomy.

I have an undeniable affinity for telescopes. I don’t just mean I love ‘em, or, more properly, lust after them, I mean I seem to accumulate them without even trying. Take the RV-6 that a kindly gentleman donated to my outreach efforts year before last. Or the Orange Tube C90, “Stella,” who came to live with us at Chaos Manor South last summer, which resulted in the acquisition of yet another scope, Eloise.

I had no intention of adding another small instrument to Chaos Manor South’s burgeoning inventory; I just wanted a decent tripod and mount for the unlooked for Stella. If you’ve experimented with photo or video tripods with even small telescopes, you know one is the worst possible solution for mounting a scope for astronomical use. I figured, however, that our nice Manfrotto might barely serve for such a small and short instrument as Miss Stella.

Not. Though the classic C90 is small with a mere 90mm of aperture, she ain’t that light. And she boasts a focal ratio of f/11, meaning a 25mm eyepiece yields 40x. Not only was the scope out of balance and pretty shaky on the tripod, leaving the altitude lock loose enough to approximate slow-motion movements resulted in the scope suddenly flopping down with near disastrous results. I’d forgotten, I guess, how bad a photo tripod is for even a Short Tube 80 refractor, much less a long focus CAT.

What to do? The obvious solution was an alt-azimuth mount intended for astronomical use. It was also obvious it is possible to spend a lot of money on a “simple” alt-az these days; those from folks like Half-Hitch, for example. These fine mounts are popular, I reckon, due to amateurs’ ongoing love affair with short-focus, high-quality refractors. The prices of modern alt-azimuth mounts, which are perfect for these scopes, are as high as their popularity. I’d already spent more money than I’d planned on the C90—I hadn’t meant to spend any at all—so I definitely wanted to lowball it mount-wise.

When in this sort of pickle, I frequently turn to Orion, the U.S. Orion, Telescope and Binocular Center. They had what appeared to be just the thing, the “VersaGo II,” rated to support 15 pounds, way more than what Miss S. weighed. The mount was priced at a very reasonable 175 bucks, so I was prepared to pull the trigger on the thing. But first, I asked my fellow amateurs’ opinions on Cloudy Nights.

Good thing I did, since a kind person piped up with: “It’s a good mount, Unk, but did you know you can get the same thing on special from Adorama badged as the Synta Sky-Watcher AZ-4 for 25 bucks less than what Orion asks, and that they throw in an 80mm f/11 refractor to boot?”

I was well aware that much of Orion’s gear is from Chinese optical giant Synta, but I hadn’t thought to look for this alt-az mount from one of the few vendors who sell Synta’s “Sky-Watcher” brand in the US of A. I hiked over to Adorama’s website, and, sure enough, there was the same "VersaGo" mount accompanied by a 3-inch refractor for a very attractive close out price (apparently Synta has discontinued this combo). I’ve bought lots of stuff from Adorama over the years, astronomy as well as photo gear, so I didn’t hesitate to send them my credit card number. They are, with B&H, at the top of the Internet camera store heap.

One afternoon, just a few days later, I returned home to the Old Manse to find a largish package waiting in the front hall where Miss D. had instructed the Brown Truck Guy to leave it. Yeehaw! NEW TELESCOPE! Yeah, I know, I was supposed to only be interested in the mount, but, still…the thought of a brand-new scope, even a “throwaway” refractor got my withered little heart doing the pit-a-pat.

First thing first was taking stock of the AZ-4 mount, which came out of the box already assembled save for its screw-in pan-handle and a tripod-spreader-cum-accessory tray, which was soon mounted where it was supposed to go via three bolts. Which were, thoughtfully, wing-nuts, which would make it easy to collapse the tripod for trips in the trunk of my Toyota Camry.

Tell the truth, I was gobsmacked at what a few dollars had got me. The mount head was sturdy, thick cast aluminum. Both axes rode on Teflon bearings and were smooth as butter. These bearings were not just smooth; they were large enough to lend the mount quite a bit of steadiness and were equipped with large lock-knobs able to apply varying degrees of friction. The azimuth axis was furnished with a Vixen compatible dovetail saddle, making it easy to mount most any telescope.

But that was not all. In a surprising fillip, I found both the azimuth and altitude axes featured well-ruled, reasonably large setting circles. These setting circles, with the aid of an astronomy program running on a computer, would make it easy to semi-automate object locating with this “manual” mount. I’ve experimented with alt-az setting circles on my 8-inch f/5 Dobsonian, and have found it fairly easy to locate objects with ‘em. You do need a computer to figure out the current altitude and azimuth of a target, but in these days when everybody (almost) has an astronomy-enabled iPhone or iPod or iPad, that’s not much of a problem.

What else? A good tripod is important, and I had scrimped there. The AZ-4 mount is available with a larger tripod, a tubular steel one (like on the CG5/Atlas mounts) with Orion’s VersaGo HD version of the AZ-4 or with some 4-inch SkyWatcher refractor packages. I didn’t think I needed such a tripod for any of the telescopes I planned to use on the AZ-4, and thought the extruded aluminum tripod that came with the 3-inch SkyWatcher and the Orion VersaGo standard permutation would be enough and would be more portable.

Yes, the extruded aluminum tripods coming out of China in the 90s had horrible reputations, but this one seemed pretty good despite the obvious skepticism of Thomas Aquinas, Chaos Manor South’s resident black cat. Not nearly as shaky as I remembered. Hell, this one hardly seemed to notice when I put the C90 on the mount. How did I put the OT 90 on the mount? I purchased a Vixen-style dovetail bracket from Orion, one with a ¼-20 bolt for attaching it to a standard tripod socket like that on the base of the C90. Screwed it into that socket on the 90 and I was ready to roll.

Not only did the skies remain amazingly clear as the Sun set, there was a nice gibbous Moon hanging. I hauled the AZ-4 and Stella into the front yard, inserted a 1 ¼-inch - .965-inch hybrid diagonal (the Classic C90 has a .965-inch Japanese Standard rear port) and had a look. Suuweet! On this sturdy mount, the OT 90 finally showed what she could do. The Moon’s terminator was dead sharp at 150x and was a welter of detail. The scope was easy to balance on the AZ-4 by the simple expedient of loosening the cradle’s lock bolt and sliding the scope/dovetail back and forth. Combine the adjustable friction axes, the Teflon bearings, and the HUGE pan-handle of the AZ-4, and movements were just smooth as silk.

The C90 has an unjustly bad rap that’s largely due to it often being under-mounted. Put it on a sturdy support like the AZ-4 and it does not give up much to the ETX-90, with its legendarily good optics. But more about Stella some other Sunday.

Since the mount seemed quite stable with the 90, I couldn’t resist trying it with some of the other grab-‘n-goish scopes in our stable. It was great with the good, old Short Tube 80, muchachos. When I equipped the StarBlast 4.5-inch reflector with a pair of suitable tube rings and a Vixen dovetail, that scope became even more fun to use than it is on its small Dob mount. Hell, I have even put one of my C8s on the AZ-4 for casual viewing—and it’s worked fine. In fact, I used the AZ-4 to support the C8 when I was testing the Hotech CT collimator (you can read all about that in the next issue of Amateur Astronomy Magazine).

After playing around with the AZ-4/C90 in the front yard for a while, I became curious about the “free” scope that came with it, the 80mm f/11 SkyWatcher. I dived back into the front parlor and into the box and retrieved the refractor’s long tube.

Once I’d removed the protective paper covering, I was confronted with, yes, a traditionally long refractor. Well, almost, anyhow. Real classic 60s refractors ran to focal ratios of f/15 – f/16, and this was a wee bit faster than that. Nevertheless, at f/11 the SkyWatcher is slower than most of the import refractors we’ve seen over the last decade or two.

One thing was immediately clear: this telescope was a pretty thing. She was adorned with a dark bronze metal flake paintjob, and sported Sky-Watcher’s cool logo, a red dot finder (identical to the one Orion gets 30 simoleons for), a long black dew shield, and a nice-looking and smooth-operating 1.25-inch Crayford focuser. The scope is mounted to the AZ-4 via a short Vixen dovetail bracket permanently bolted to the tube.

The optics? A look down the business end revealed a nicely coated, near-invisible objective in a non-adjustable cell. Peering through it revealed an adequately blackened tube interior and a series of baffles to reduce light scatter. All in all, my free scope was rather cool. Well, except for the diagonal. It came with a 120-degree “terrestrial” model. Those things almost always introduce annoying aberrations, including diffraction spikes, so I didn’t even try it, inserting instead a groovy William Optics dielectric job.

Yeah, my new refractor, my big—well, long anyhow—refractor, looked appealing. Even to me who hasn’t had much of a track record with lens scopes till recently. I came into amateur astronomy in the mid 1960s, a time when refractors were in decline, at least for rank and file amateurs. We were all equipped with 4 – 6-inch Newtonians and believed with near holy fervor that our telescopes were far better for anything than those old, odd, small refractors.

Course, Unk and just about every amateur of the day, young or old, spent considerable time drooling over refractor porn in secret. I am talking about the glorious catalog of Unitron, whose pages were festooned with what surely must be the most beautiful achromatic refractors ever made. Nay, the most beautiful telescopes ever made.

These gleaming white refractors didn’t come cheap, alas. A 60mm alt-az rig, the Model 114, at the bottom of the Unitron lineup, cost a cool $125.00, which is equivalent to at least 850 of our shrunken dollars. I wanted one nevertheless. Who wouldn’t? And I convinced myself that the 60mm, despite its small aperture, would surely show me things invisible to my humble Edmund 4.25-inch Palomar Junior Newtonian.

As I have written before, though, that idea only lasted till I got a look through a Unitron. I couldn’t afford one of those wonder scopes. Nobody in our little club, The Backyard Astronomy Society, could afford one. But there was one feller in the neighborhood, Eddie, whose parents were a bit better off than any of ours who was able to achieve the dream, at least at the Model 114 level.

I had been friendly with Eddie for a long time; in fact we were basically best friends for several years. But one day we’d had an argument that resulted in a serious falling out. I don't mind admitting it was my fault, brought on by the misguided and ignorant hard-headedness I sometimes displayed as a youth and have struggled to overcome in adulthood. I tried to patch things over a couple of times in my bumbling fashion, but he’d have none of it.

I let things be with my former friend--what else could I do?--till one evening when I was assembling the Pal Junior for my Saturday night observing run and noticed my former friend was setting up a telescope of his own in his backyard three houses down. I had a sneaking suspicion it wouldn’t be just any telescope, either, but a Unitron telescope, which I knew he’d been bugging his dad about for a while.

I was curious enough that I swallowed my pride and walked over to see if I could cadge a look. My ex-buddy didn’t have much to say, but he did give me a quick peek at the Moon. I was hardly impressed. Luna, at about 100x, looked considerably dimmer than she did in my Pal. She displayed an orangish tint, too, unlike her visage in the Pal, which was silvery white. Finally, I thought I could make out a fringe of spurious color along her limb, though it was subtle.

I thanked Eddie for letting me have a look, and walked back home feeling blue, both because I now saw that nothing was likely to put our friendship back together, and because a telescope that I expected to be a wonder had turned out to be something less. I was right to feel bad about our friendship, and I'd have been more right if I'd taken a hint and moderated my sometimes rash behavior. The refractor? I was wrong about that. No, a 60mm can't compete with a 100mm, that's just physics, but that old Unitron could deliver remarkable views nevertheless.

And there things stood for thirty years. Oh, I was aware refractors, in the form of APOs, were much better, completely different animals in fact, as the 80s gave way to the 90s. But did I want or need one? Heck no. That changed some when I took the plunge with a Short Tube 80 and found out how wonderful the right—short focal length—refractor can be. Not long after the turn of the century, your old Unk could occasionally be found observing and imaging with a couple of cool APO refractors of his own. But a long lens scope like the Unitrons? No way.

But here I was with a sorta-Unitron all these years down the line. Not an f/16 60mm, but an f/11 80mm, which was pretty close. Would a modern achromat please me more than that long ago Model 114 had? I doubted it. Optics have gotten better over the years but this was still a plain old achro, and 3-inches at f/11 would undoubtedly display more color than 2.4-inches at f/16.

Optical quality? Hard to say what to expect. The Chinese have got pretty good at spitting out mass-produced optics, and despite what those of us who lived through the Unitron days “remember,” pretty as those scopes were, their optical quality was not always as high as their prices.

The Moon was still beautifully positioned in the sky, so I carefully maneuvered that long tube out the front door and onto the AZ-4. Fired up the red dot finder and moved the scope till the dot was on Luna. Amazingly, the finder’s aim was pretty much dead on out of the box. I inserted one of the two eyepieces that came with the 3-inch, a (modern) silver-top 25mm Plössl, into the diagonal and had a look. Well, well, well. Not bad. Yes, there was a little color along the limb, but not much. I further noted that the shadows along the terminator were black, not the purple they had been in a buddy of mine’s 4-inch f/10 Chinese refractor. Above all, the craters and mountains were satisfyingly sharp.

Wasn’t much else to see in a clear but hazy and light polluted sky other than Luna, so I spent quite some time with her, bumping up the power with the other included ocular, a 10mm Plössl, and running into the house for better eyepieces. The Moon held up much better at over 100x plus than she does in the ST80, which begins to struggle at that power-level. Despite the length of the tube, the AZ-4 maintained its steady-buttery character. I had quite a time and became curious as to what else this 3-inch refractor, which hearkened back to not just the 60s, but to an even older amateur astronomy, might show me.

I got at least some idea of that at last summer’s Boy Scout Jamboree. I was tired and there was a near-full Moon in the sky. I couldn’t bear the thought of manhandling even the RV-6 into the car. What the heck. The 3-inch sure looked like a telescope, which should impress the boys, and it would be the job of 2-minutes to get her into and out of the car.

If you’ve read the above blog entry, you’ll know Eloise acquitted herself well. Eloise? I name my telescopes, all my telescopes, and there was a certain saucily mischievous quality to the Sky-Watcher that suggested Kay Thompson’s champagne bottle-wielding heroine.

What did we see? There wasn’t much in the streetlight and Moon-blasted sky of the Jamboree, but we did see Jupiter’s currently subdued Great Red Spot with fair ease, a pretty good feat for a 3-inch telescope. Quite a few Messier open clusters looked pretty, too, with Eloise with her comparatively wide fields being the only scope who could give the boys a good look at the rising Pleiades, which several of them had noticed. The Boy Scouts, yes, gravitated to Eloise because she best fit their idea of what a scope should be. I liked the simplicity of the old-school refractor and her alt-az mount after a long, hard day at the salt mines. And I found I still enjoy astronomy the old fashioned way.

By “old fashioned way,” I don’t just mean with a long refractor, but with a telescope without any technological oomph whatsoever. No computers, no go-to, not even motorized tracking. Yes, UNPLUGGED ASTRONOMY. You-all know I am a big proponent of go-to, but I like to keep my hand in when it comes to star hopping, and Eloise made that Real Fun with her simple red dot sight and smooth alt-az mount, even in skies where there weren’t many “guide” stars.

Old fashioned, yeah, but I did make a couple of concessions to modern times in that I used my iPod and SkySafari instead of a print atlas to locate objects, and a green laser instead of my index finger to point-out objects. The laser and the iPod weren’t exactly retro, but both delighted the youngsters.

I saw a little more with Eloise just last week, last Thursday night to be exact, at the Possum Swamp Astronomical Society’s bi-annual public star gaze. As before, I was tuckered on this weeknight, wimped-out, and threw Eloise in the car instead of the Dynascope or a C8. Again, the refractor performed beautifully. Not just on the Moon, but on the few deep sky objects peeping out of the light pollution at our in-town observing site. M42 was surprisingly sweet, with the stars of the trapezium well-resolved little diamonds at 44x in a 20mm Orion Expanse eyepiece.

Eloise has continued to grow on me as the months have passed. I’ve got a lot of observing projects in the works, including the vaunted and ongoing Herschel Project, but I am thinking of making room for one more. I’ve downloaded a copy (available for free online) of the classic observing guide of the early 20th Century, the Reverend T.W. Webb’s Celestial Objects for Common Telescopes (1904), and have begun transferring some of its objects to SkyTools 3. My goal? To see what I can see of Webb’s objects, to see how my impressions of the Rev’s DSOs and double stars compare to his using a similar class instrument—sweet Miss Eloise, that is.

Next Time: The Moon won’t be out of the way till week after next and I’ve got another lousy cold anyway, so maybe next Sunday’s blog will be something a little different. After that? Miss Dorothy and I are planning a Herschel Expedition to the Chiefland Astronomy Village. Oh, and I am currently working on a project that involves binoculars, BIG binoculars, which I hope to tell you about well before we make tracks for Florida.

Comments:
Hello Unk,

Thanks for another great post. Hope you are feeling better soon. Once you make it to Chiefland, please come visit us in 'The Swamp.' It has been a while...
 
Call me lazy, but I would never own a telescope unless it had a clock drive mount....
 
I like drives, too, but there _is_ a certain attraction to "point and shoot" astronomy, too. ;-)
 
Nice post! I got the same 80mm refractor/AZ4 combo last year and I have been very happy with both scope and mount. I'm also delighted to hear that the mount will hold scopes up to and including a C8. I had just been thinking about getting a mid-sized CAT.

Speaking of, I am curious, if you had your choice of a 5" Mak (Orion Apex 127) or a 6" SCT (Celestron C6) for mostly planetary/lunar and a little deep sky on the side, which would you choose? I already have an XT10 for nights I am serious about the deep sky; this would be a more portable scope for nights when I don't have the energy for the big gun. I know you have better things to do than answer silly question in comments, and I'll be grateful for your thoughts.
 
I have always enjoyed my 5-inch ETX MCT...but there's little doubt the C6 is a more versatile scope with very good optics. Shorter in focal length with wider fields than the Orion MCT as well...
 
Hi Rod

For a simple up/down swivel mount I have been very satisfied with my Vixen Porta Alt Az mount for a few years now using either my WO Megrez90 or an F4 6" Newtonian made by The British OrionOptics company. It is very steady, has a smooth action and comes with slow mo controls as standard- eeesential! I have used either combo much more often than making the effort to drag out my 12" LX90 plus wires, heaters, focuser etc, etc.

Love the blog- my Sunday treat.

Keith James, London, England
 
Thanks, Unk, your thoughts are much appreciated. I'm with Keith--getting my weekly fix here is one of the prime pleasures of the weekend. Keep 'em coming!
 
Hi Unk...I enjoy reading your posts and yes, I'm late to the party, but I have some news. As of 1/2015 finding anyone who even acknowledges the existence of the AZ4 mount is problematical, trying to buy one dictates moving to EU.

Well surprise! Good old Orion is about to get some AZ4's in (Versa Go II on their page) and the price is right $178 US with free shipping. Doesn't have the steel legs, but those can be found on Cloudy Nights or Astromart. Nice bargain for those looking for this mount.
Pete
 
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