Sunday, October 12, 2014

 

The IBM GEM


“What the hail is Uncle Rod goin' on about now?” The GEM, the German equatorial mount, I am referring to, muchachos, is the time-honored Synta (SkyWatcher) EQ6 (a.k.a. Orion Atlas). It is both an amateur astronomy classic and, best of all, an affordable classic.  “OK, Unk, but where does the IBM business come in?”

The EQ6, which has been a fixture of amateur astronomy for over a decade, is much like the original IBM PC and its clones. It is out there in large numbers, is simple but reliable and long-lived, and, because of those things, there are tons of aftermarket accessories and add-ons for it. Countless observers and imagers use it; in Europe and the UK, it’s unusual to find an astrophotographer not using an EQ6.

Not that the EQ6 got off to a roaring start. The original non-goto version of the mount showed promise, but that was about it. When I saw my first example of this Chinese mount right after the turn of the century, I was impressed by its heft and appearance. Its large equatorial head weighed over 40 pounds, and its design style was an obvious “homage” to Takashashi, if not even in the same Solar System when it came to fit and finish.

Yeah, it soon became evident that the EQ6 was no Takahashi, and not just because it was cast, and somewhat roughly cast (there's plenty of casting rather than machining on the Tak mounts, too). Its performance was also nothing like that of the EM-400 that inspired it. It didn’t track very well. The periodic error inherent in its gears was large and not overly smooth. Oh, you could take long exposure deep sky images with the mount, but not easily. You’d be throwing out a lot of frames due to trailed stars, even if you were auto guiding the mount.

Surprisingly for some of us, Synta, who was becoming the 800-pound gorilla of the bargain astro-biz, didn’t leave the EQ6 as it was. They soon brought forth a new model, a goto version of the EQ6, variously referred to as the “SynTrek,” “SynScan,” and “GT” version. Not only did this thing have a computer hand control, the SynScan, it had, we were told, had its gears and motors replaced with more imaging-friendly ones.

That was all right nice, but Unk wasn’t interested, even at the very reasonable price Orion wanted for the goto version, 1400 dineros. I already had a goto GEM, a CG5, that worked adequately well for my modest requirements. Or it did ‘til one windy night Down Chiefland Way.

Unk’s EQ6 story really begins back in April of 2006, when I was at the Chiefland Astronomy Village for the vaunted Spring Picnic. The skies were not great; they were hazier than I’d have liked. But they were not that bad, either. What was bad? The pea-picking wind. Despite the haze and occasional clouds, I was seeing a lot with the combo of my C8, Celeste, and my old Stellacam 2 deep sky video camera. Or I would have been seeing a lot if the CG5 mount hadn’t trembled like a sinner in the hands of Elmer Gantry with every wind gust.

Could be a comet, could be a custard pie...
I wasn’t happy despite the fact that by keeping the camera rolling I got some nice pictures, including some good footage of pretty little Comet Schwassmann–Wachmann.  It wasn’t easy getting those shots, and most of my footage looked like the image here. I followed my friend Pat Rochford’s suggestion, and removed the dew shield from Celeste, which helped some, but not enough.  It was clear what I needed: a sturdier GEM mount.

The CG5 was fine for video most of the time, but obviously not all the time. It also did well enough for Unk’s undemanding prime focus deep sky imaging, but it would have been nice to have a mount that delivered a larger proportion of good frames than the CG5 could. Of course, once Unk resolved, some months after that Spring Picnic, to think “new mount,” came the hard part. Which one?

I was awfully tempted (and still am) by Losmandy’s G11. It was several steps up from the CG5, to say the least. But, given the relatively few astrophotography worthy nights we get down in the Swamp, I wasn’t convinced I needed to spend even the relatively modest amount the G11 commanded, about 3K. Not when I might be able to get by for half that. I’d been hearing a lot of good things about the Atlas/EQ6, and began turning in that direction.

Unk being Unk, it took me months to screw my courage to the sticking point and give my credit card number to Orion, the sole U.S. seller of the EQ6. What pushed me over the edge were two things. First, the Atlas’ hand control, the SynScan, was similar to the Celestron NexStar HC. There were plenty of differences, I knew, but I’d still be on relatively familiar ground.

Secondly, there was a program for the Atlas that was a lot like my beloved NexRemote, which allows the Celestron mounts to be operated with a computer sans hand control. EQMOD for the SynScan mounts was like NexRemote, and had even more features.

The only question remaining concerned the “Hand control or no hand control?” option Orion allowed you to exercise seven years ago. Despite Unk’s famous tendency towards thrift (stinginess, that is), I decided to get the HC. There’d surely be times when I wouldn’t want to tote a PC along to run EQMOD. That turned out to be true and, as you’ll hear, as the SynScan firmware has continued to mature, the more I’ve found myself using the HC.

Due to the Swamp’s horrendous weather in the fall of 2007, the Atlas, which I’d received in October, didn't get its first serious night under the stars until January of ’08. And when it did get that night, I used EQMOD exclusively. You can read the whole story in this entry, but I will say here that I am still amazed at my good results despite plenty of fumbling.

Setting up on the Chiefland Astronomy Village field on a surprisingly chilly January Florida night, I was skittish. Mostly about one thing. The SynScan HC at this time did not include a built in polar alignment routine. Neither did EQMOD. You polar aligned the Atlas the old-fashioned way, with a polar scope. Visions of dim polar scopes and poor polar alignments danced in Unk’s post-Christmas-letdown head.

I needn't have worried. The EQ6 has one of the best polar borescopes in the business. No, it’s not as good as the legendary Takahashi polar scope, but till the coming of the iOptron polar alignment scopes, it was at least second best with a legible, illuminated reticle and, unusual for imported polar scopes, a halfway decent apparent field of view.

Polar aligned, I goto aligned by syncing on a few, and only a few, stars with EQMOD and the planetarium program I used in them days, Cartes du Ciel. On that first night, any target I requested anywhere in the sky was somewhere in the field of the C8 when the slews stopped. On my second night in Chiefland, the mount delivered round stars in three and four minute (guided) subframes without complaint.

Otherwise? This was one big sucka. The Atlas’ equatorial head literally dwarfed my friend Carl’s Celestron CGE. Not that that was all to the good. The weight of the mount, 40-pounds plus for the head alone, was to often impel lazy old Unk to use the CG5 instead. Its heft was undeniably impressive though. And so was its slewing. The Atlas uses stepper motors rather than the CG5's servos and is about a million times quieter.

How about that hand control? The few times I tried it in those early days, I was not impressed. So-so gotos at best, and very few features compared to the NexStar HC. It wasn’t just the polar alignment routine that was missing, but even the ability to goto an inputted RA and declination—you had to enter your comet or whatever as a “user object.” Not hard, but it would have been easier just to punch in RA and dec numbers.

One thing I did like about the SynScan was its Polaris H.A. readout. Once you entered the time, date, and site information, the HC would display the current Polaris hour angle. You could then use that in conjunction with the right ascension setting circle to get a more accurate polar alignment with the polar scope. Mucho bettero than what was obtainable by merely matching the constellation pattern on the reticle to the constellations in the sky.

I continued to use the Atlas with EQMOD, if not that frequently. Let’s face it: it was just easier to transport and set up the CG5 for deep sky video. About the only time the Atlas got used was when Unk wanted to do DSLR imaging, which, by the end of the last decade, had entirely replaced CCDing in his affections. I’d probably have used the Atlas more if I could have left the computer at home, however.

There were plenty of nights that would have been Atlas nights at the Possum Swamp Astronomical Society Dark Site if I could have run just with the SynScan. Those nights that were windy enough to challenge the CG5, but which were not quite clear enough to make me want tote laptop, laptop battery, wireless gamepad, wireless gamepad receiver, USB hub, and all the other junk needed for an EQMOD run.

There things remained for a long while, ‘til 2012 to be exact. That was the year Synta really buckled down with the SynScan firmware. Oh, they’d continued to update it in the four years I’d owned the mount, but the updates were incremental and didn’t contain many new features. Certainly nothing like the big Celestron GEM firmware update of 2008.

Then, everything changed. In 2012 Synta/SkyWatcher issued the beta release of an update that contained lots of new stuff, including a polar alignment routine identical to the AllStar of the company’s NexStar mounts, something everybody was raving about. I gave the new firmware a good check ride in September of that year, and found the beta was mostly all there, if still containing a few rough edges.

The polar alignment routine worked, and the goto alignment had been improved. The star choices the HC offered during alignment were more likely to produce good goto accuracy than formerly. Before the new firmware, if you just accepted the first three stars the HC picked, you were almost guaranteed poor goto performance.

The current firmware release for SynScan v3.35, has mostly rounded off all the rough edges I discovered at the CAV that September of 2012. It’s still maybe not quite perfect, but a new SynScan firmware release is, I understand, in the offing, and I believe it will finally tie the bow on the SynScan hand controller package.

It wasn’t just the new firmware that helped with the hand control’s accuracy. What probably improved it most was that four years down the line Unk finally read the manual’s instructions regarding the HC alignment. Before, I’d tended to use the SynScan just like the NexStar, accepting whichever stars it first offered. As above, that led to fair goto accuracy at best. One day I was looking up something else in the manual, however, and noticed there were rules for alignment star choice.

According to the instructions, the first two stars should be separated by at least three hours of right ascension. Separation in azimuth was not as important, especially with a decent polar alignment. Star three, the book said, should be between declinations 30 and 70, north or south…

Hmmm…why not give it a try? Sure would be nice to get the HC working reliably. I hauled the mount out to the dark site, did a three star alignment, rejecting stars the HC offered that did not follow the above rules, and started gotoing my gotos. Guess what? The mount never missed a beat with the C8. Ever’thing was in a wide-field 12mm eyepiece. The new firmware, as I found out in Chiefland, had refined the hand control’s ability to choose “good” stars, but I am still careful to monitor the choices, and doing that still seems to help with accuracy.

Sometimes you can’t choose good stars, however. The mount does not like alignment stars that are too high in the sky, too close to the Meridian, that is. But sometimes you’ve got no choice. A tree (whose days are numbered) blocks the southeast sky at the New Manse, so I have to use the stars I can see. Nevertheless, on a recent DSLR run from the backyard, the mount placed anything I requested in the field of my Canon 60D with the C8 at f/6.3.

Starry Night Pro Plus and EQMOD...
The upshot of all these things is that I am now using the SynScan hand control more than EQMOD. That may change as I become more comfortable with the new planetarium program I am now using, Starry Night Pro Plus 6 (yes, Skeezix, I know it’ not new, but it’s new to me for reasons you will read about some Sunday soon). I will undoubtedly go back to EQMOD for some imaging runs, but it’s nice to know that I don’t have to use EQMOD if I don’t feel like using it.

So you’ve got your Atlas EQ6. It works good. But you’ve got the sneaking suspicion that it could be More Better Gooder. There are things that can make the mount better. A sturdier tripod is one—the 2-inch steel-legged tripod that ships with the Atlas is not bad, but there is little doubt it is the weak link for this heavy mount.

There are a couple of ways to solve the tripod conundrum. The obvious way to do that is by replacing the sucka. While I don’t know of a replacement tripod being manufactured specifically for the EQ6, you can buy adapters that can let you use better tripods. My CAV buddy Paul Lavoie, mounted his CGEM, which is similar to the Atlas, on the large Meade field tripod (the one for the 12-inch SCT), and you could do that same for your EQ6. It does make a difference.

Want an off the shelf solution? Mount guru Ed Thomas sells the famous Berlebach tripods configured for the Atlas through his company, Deep Space Products. They do NOT come cheap, but the results will most assuredly be better than the stock tripod and they will also most assuredly lend your mount that touch of class.

If, like Unk, the Berelebachs are a mite too rich for your blood, there is another way. Maybe not quite as effective a way, but close. The problem with the Atlas tripod is not really the tripod legs, or at least not just the tripod legs. It’s that pitiful little spreader. A tripod spreader should be a sturdy thing that doesn't just provide you with a place to stow eyepieces, but something that holds the legs firmly apart and stabilizes the tripod, which the Atlas’ puny cast spreader cannot do.

For once, campers, the fix is easy. It comes from an outfit called “TPI,” Telescope Performance Improvements. Their beautiful (and strong) spreader attaches to the lower ends of the stock tripod legs and holds them firmly apart. It folds easily for transport and does not make a nuisance of itself, either.

You can kick it up another notch with one of TPI’s big accessory trays that clamp to their spreader. Install one, put your jump-start battery on that, and your rig is even more stable (we used to hang gallon milk jugs full of water from our tripod heads to stablize ‘em). While your tripod still won’t look like a Berlebach, it will be near about as steady, and the TPI gear also makes the old tripod look much nicer—almost gives it that touch of mink. The damage? About $350.00, which is a freaking bargain if you’re trying to get the mount to accommodate a heavy OTA or are going after long exposures at longer focal lengths.

If you just want to keep it steady for imaging with a C8 or a small medium refractor? I still recommend either the TPI spreader or one of Ed’s tripods, but if you are as cheap as Unk, you might be able to get by with a set of Celestron’s vibration suppression pads for about 40 bucks from Unk’s fave photography superstore, B&H.

What can you do to help the mount itself, assuming your OTAs are larger than Unk’s C8 or your imaging goals more lofty? Have a stroll through the web pages of ADM. They have several products that can improve your mount, but the big deal is a replacement saddle that will allow your EQ6 to use OTAs with Losmandy D dovetails rather than Vixen dovetails. There is no question the Losmandy dovetail setup makes for a steadier scope once you get past a C8 or a C102.

What else can help with that C11 or Meade 12? A longer, stronger counterweight shaft. Orion and others will sell you a replacement shaft that will allow your heavy OTA to balance with fewer/lighter weights. Do keep in mind that these solutions will mean giving up the Atlas’ convenient retractable counterweight shaft feature.

“That’s all cool, Unk, but it ain’t what I had in mind. What I am thinking about is HYPERTUNING the doggone thing.” Some folks do dig into their mounts, replacing everything from gears to grease in order to (try to) improve their EQ6s’ performance. This “hypertuning” can include not just regreasing, but polishing of various parts, remeshing gears, replacing some parts, and modifying the Atlas somewhat creaky altitude and azimuth adjuster system (if you can call it that).

Should you? I am inclined to say, “no.” It’s too easy to mess something up bad unless you are considerably more mechanically inclined than Unk. If you think your mount needs a rework, let Ed Thomas do it instead. He will do it right. However, as he will tell you, hypertuning will not turn your mount into a Tak or an A-P. It can help the mount live up to its potential, but if you need an A-P mount, buy an A-P mount. Luckily for our bank accounts, most of us don’t need one.

And that, muchachos, is purty much the Atlas story till now. Should you get one or wait for the next big thing outa China? As always in amateur astronomy, “that depends”—on you, your resources, and your goals. But the Atlas is a solid, time-tested, uber dependable mount. It ought to tell you something that Synta, despite introducing the newer and “better” including the CGEM and the AZ-EQ6, continues to pump out the old reliable. That’s because it is the old reliable. Recommended, y’all.

Next Time: I'm rearranging the schedule...to get y'all in the mood for the fall star party season, let's go to the 2002 Peach State Star Gaze!

Comments:
Rod: I purchased one of the original Non-goto EQ6s. It was indeed rough, but it kept my Celestron 9.25 reasonably stable for visual stuff. My astronomy hobby got put on the backburner and pulling out the big scope just wasn't in the priority mix. Things are changing now so I want to resurrect and improve the original mount so that I can mount the scope + camera. Are you aware of any sites/vendors that can improve/upgrade an original mount to at least to the standard that is present in the EQ6's today.
 
HI Keith:

I can't point you at any specific websites, but I am pretty sure there are outfits offering upgrades like you have in mind. You might want to join the EQ6 Yahoogroup and ask this question there. The sticking point might be the price...it might be cheaper to sell what you've got and buy a new Atlas. I know plenty of visual observers still use the original mount...
 
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