Wednesday, January 09, 2008


Down Chiefland Way with EQMOD

Actually, this entry ain’t really about the Chiefland Astronomy Village, though those of y’all who’ve been reading this blog for a while know the high regard Your Old Uncle Rod has for the skies—and the people—of CAV. No, this is really about the new telescope mount that has come to stay at Chaos Manor South, the Orion Atlas (Synta/SkyWatcher EQ-6). Well, that's not quite right, either. It’s really about an amazing piece of astronomy software, EQMOD, which turns a good mount into a great one.

In recent times I’ve begun to drift away from the fork mounts I’ve used for the better part of three decades. That process began with the arrival of the Celestron CG5 at the ol’ manse three years ago. Despite its low price, this German Equatorial Mount has worked impressively well, displaying surprising go-to accuracy (at least as good as the NexStar 11). It also seemed easier to use for imaging. The silly little thing took picture after auto guided picture with an SBIG camera. Couldn’t ask for more, could I? Actually, I could.

One weekend I was down at Chiefland with the C8/CG5 and a Stellacam II, traveling light. I was having a great time videoing the deep sky…until. The wind came up. With a good wind (not quite a gale but strong enough), the CG5 began to shake like a sinner in the hands of Elmer Gantry. Removing the C8’s dew shield helped some, but not quite enough. Despite the fact that this was the only time I was even partially skunked by the CG5, I decided another GEM for the C8 was in order. Something with a little more payload capacity. At least for those times when I wanted to do long-exposure prime focus imaging.

What to choose? I eliminated the high-priced spread, the Astro-Physics and Bisque mounts, right off the bat. I do dream of a Paramount occasionally, but that will wait for retirement--if then. The less expensive gear seems more my style, and part of my enjoyment is seeing what I can get out of "simple and cheap." Frankly, y'all, I have neither the skies nor the talent to justify spending 10 grand on a freaking telescope mount. 

Next tier down? Even the Celestron CGE and the Losmandy G11 seemed a mite rich for my blood at this juncture considering the “huge” amount of spare time I have to actually observe with the C8, much less do astrophotography. Vixen Sphinx? In my opinion, that is getting into the “too-light” range again--and I was less than impressed with the attitude of the US Vixen distributor when I encountered them at the Cherry Springs Star Party a while ago. I also have some doubts about the usability of Vixen's Starbook controller. Big doubts.

Which left the Synta EQ6 SynScan go-to (a.k.a. the Atlas EQ-G for us Americans, who have to buy it badged "Orion"). This looked to be a nice, big (and heavy at 40 plus pounds for just the GEM head) mount for an impressive price, about $1500.00 with a go-to hand controller from the U.S. distributor, Orion. I chose the $1500.00 version with the HC despite the fact that the identical (including electronically) mount is available without the hand control for 300 bucks less. This would have been a viable option for me, since, as you'll see, I didn’t plan to use the HC all the time—or most of the time—for gotoing. I did think it would be nice to have the hand control for those occasions when I didn’t want to mess with a laptop computer loaded up with a program called EQMOD.

EQMOD with settings opened...
What’s EQMOD? In a nutshell, it’s an innovative (and free) ASCOM driver developed by Mon Sarmiento and a team of talented programmers. It allows the hand control to be left at home and the scope run directly from a laptop (just like NexRemote for the Celestron mounts). Why would anybody want to do that? The Synta hand control looks a lot like the NexStar HC, but it is a different beast despite being made by Celestron’s parent company. Its software is simpler and offers fewer features. Goto is good, but maybe not as good as it could be. In addition to adding features and helping with goto accuracy, one especially Good Thing EQMOD does is furnish a wireless hand control—in the form of a wireless computer gamepad; again, just like NexRemote. That is something I came to really like about the Celestron software.

When the Atlas arrived at dear, old Chaos Manor South, naturally so did the clouds. I did have the opportunity for a few outdoors tests after Christmas, but these were limited. Most of my testing was done in the living room, but allowed me to check that both the mount and EQMOD seemed to work fine. There was one small hiccup:  the DC power cable made a poor connection with the mount. At times, I would lose power, or the power light would begin blinking, indicating low voltage. This was made worse by the fact the mount power connector rotates with the RA axis.

I was slightly put out by this glitch, but found I had a Celestron power cable on hand that fit better and worked perfectly. In their defense, a quick email to Orion, brought a new and functioning DC power cable to Chaos Manor South in just a couple of days.

As above, after the holiday I got the Atlas outside for a checkout under the stars--at my observing companion, Pat's, observatory in Fairhope, Alabama during a brief respite from cloudy skies. Observations? The goto was good enough after a three star alignment, but not as good as on my CG5. On the other hand, the mount's stepper motors were far, far quieter than the servos used in the notoriously noisy CG5,

The next step was to see what EQMOD could do to improve the already impressive--mechanically, anyway--mount. The software was remarkably simple to get going, and, other than a wireless gamepad (a generic one works fine), it only required the purchase of two inexpensive additional items: a standard serial cable and an EQDIR interface module from Shoestring Astronomy.

The EQDIR ($35.00) is a small electronic widget that plugs into the laptop’s serial port (or a USB – serial converter cable); the serial cable plugs into EQDIR, and the other end of that cable is connected to the mount’s DB9 hand control connector (yep, DB9—none of that RJ nonsense for big dog Atlas). What EQDIR does is translate the serial-speak (RS-232) coming out of the laptop to the mount-speak (TTL levels) Atlas understands. Like every Shoestring product I’ve used, it worked like a champ. Indoors, anyway. As 2007 wound down, the weather just got worse and worse.

If the Possum Swamp skies wouldn’t cooperate, what would I do? Grab my trusty 1995 Ultima 8 OTA and the new Atlas and head for Chiefland, Florida for a couple of days, that’s what. In addition to checking-out the mount, I was hoping to get a few DSLR images for my forthcoming new SCT book, Choosing and Using a New CAT (Springer). That in mind, I packed a ton of imaging gear into the Camry and lit-out for the Chiefland Holiday Inn Express (for me, “roughing it” these days means staying in a motel) and the Chiefland Astronomy Village.

The CAV field during one of the big spring star parties...
Arriving in the little town after six and a half hours  on I-10 and (partially) scenic Highway 19, the Florida - Georgia Parkway, I checked into Chiefland's Holiday Inn Express and immediately headed to the storied observing field. I was pleased to see that five or six other hearty souls had joined me for a weekend on the slightly chilly post-Christmas observing field.

In short order, I had the Atlas set up and its (jump start) battery connected, the C8 on the mount, and the laptop and EQMOD ready to roll. That was just the beginning, of course. There was also the EZ Up tent canopy, the camp table, the Toshiba laptop, three or four gear boxes, a sizable eyepiece case, batteries, extension cords, and the other numerous and sundry items I bring along for an observing run. And there was even more stuff in the Camry's trunk, imaging stuff I didn't plan to mess with on the first night.

For the second evening, there'd also be the USB cable to the Canon 400D, the DSUSB (long exposure control) interface box and connection to the camera, the Shoestring GPINT-PT (guide port interface) module and the ST-4 style connection to the Atlas, the PhD Guiding program, and Nebulosity for camera control and image acquisition. Those things would wait for night two of my two night Chiefland adventure. I intended to devote night one to the mount and EQMOD and night two to picture taking.

Set up on the field, there was still an hour or two to go before sunset, so I made tracks for the Chiefland Walmart for a few items. One of which was bottled water. Even when it is cool, you have to keep yourself hydrated. You may not feel thirsty, even if you begin to get dehydrated, but your get up and go, your stamina, will have evaporated and you'll be lucky to make it to midnight. Other than that, just the usual items: Jack Links Jerky and granola bars for midnight snacking, Monster energy drinks to refuel myself as the clock ticked toward morning, and a few bottles of Guinness for in the room relaxing after the run.

Chiefland's Holiday Inn Express...
Back on the field with the Atlas and C8 uncovered, one thing that blew me away? I considered the Atlas a bargain mount, so it was a real eye-opener to see how big its mount-head looked compared to Carl Wright's nearby Celestron CGE. Heck, the Atlas dwarfed it. Massiveness is good, but is no guarantee of precision when it comes to mounts, of course. That’s measured in go-to accuracy and periodic error or lack thereof.

The details of the mount's PE characteristics, like the minutiae of all the gear and software mentioned above, is perhaps a subject best left for another installment. But even without talking arc seconds of error, the way a telescope mount acts when its told to go-to something and what happens when you give the scope a sharp rap upside the head—err “OTA”—go a long way toward telling you what the mount’s made of, so to speak. As would become evident after just a few hours of use, The Atlas EQ6 is one heavy mutha, in every way.

Despite my at home tests, I was a bit skittish about the EQMOD software, and that's why I'd decided to devote the first night to getting comfortable with it. It turned out I needn’t have worried. If anything, it’s even easier to get going than NexRemote, which ain’t no slouch in that department.

Start out with the Atlas in its normal Home Position (counterweight down, tube pointed north). An at least halfway decent polar alignment should have been done via the built-in (and excellent) polar scope. With the mount connected to the laptop via the serial cable and EQDIR, start-up the planetarium program of choice. That can be anything as long as it is ASCOM compatible. I chose the new beta of Cartes du Ciel, a solid and wonderful (and FREE) program I’ve used for years. Why didn’t I use my “usual,” TheSky 6? Tests showed a few problems using ASCOM and EQMOD with TheSky. Note that this is the only even marginally ASCOM compatible program I found to have difficulty with EQMOD, and I've been told that by tinkering with their computers some folks have been able to make the current version of  TheSky work with ASCOM.

Cartes du Ciel
Anyhoo, start up Cartes or whatever, mash “connect to scope,” and choose EQMOD as the scope/driver. Up pops a driver window. Click the “setup” tab and enter the usual stuff any ASCOM driver will want to know--like latitude and longitude. Do make sure these values are the same as those in the planetarium. If you don’t, the mount will act squirrelly—as mine did when I was playing with EQMOD out in Chaos Manor South's backyard one night when I thought I spied a sucker hole. The Atlas continually pointed the telescope at the ground until I discovered EQMOD had the coordinates of Manila, not Possum Swamp.

Data entry complete, this is where things get interesting. It’s time to do a goto alignment. Still in “setup” on EQMOD, click “n-star” alignment. What that means is that you are going to align on three or more stars (there is a one-star option that can work well if the mount is precisely polar aligned). A window will pop up with buttons that allow stars to be accepted and the alignment ended when all the stars have been centered. There are also directional buttons that can be used to move the scope to point at chosen alignment stars. If you’re like me, though, you’ll be using a wireless gamepad. One of the joys of EQMOD is that it will work with almost any joystick or game controller including the 10 buck wireless job I picked up at WallyWorld. Next step is to choose some alignment stars, and that’s where EQMOD takes a different path.

Rather than choosing stars from a list on a real or virtual hand controller, with EQMOD you click on stars shown on the planetarium program’s screen—any stars. Select Capella, click “slew to object,” and off the scope goes. When it stops, center the star and click the button on the gamepad that maps to “accept star” (there’s a utility in EQMOD’s set-up that allows you to assign gamepad button functions as desired).

When the Atlas stopped at the first alignment star, a look through the finder showed Capella was just a degree or two away. My next two stars, Castor and Rigel, were not just centered in the finder; they were in the C8 eyepiece at 100x. When these stars are centered and accepted, hit the gamepad’s “end alignment button.” How many alignment stars? I did three on the eastern side of the local meridian and quit. According to EQMOD's developers, best results are achieved if at least three on the east side and three on the west side of the meridian are used. Being lazy, I just left it at three.

November 2007:  Atlas has arrived!
Results? Anything I asked for from horizon to horizon was somewhere in the field of an 82-degree 12mm Nagler eyepiece. I have no doubt that if I’d done more stars performance would have been even better, but this was more than good enough for visual observing or even for imaging with the Rebel XTI at f/6.3.

How do you actually send the mount to objects, though? Just click on an object, any object, on the planetarium program's screen and select “slew to" (or whatever command your software uses to send the scope on its way). Away she goes and said object is in the eyepiece. Simple, easy, sweet.

If all EQMOD did was allow the mount to do more accurate gotos than what the SynScan hand control allows, it would be impressive, but it does a heck of a lot more and features are being added all the time. There’re already add-on modules for things like PEC recording and refinement, and a Tour sub-program that’s intuitively easy to use. One of the next things on the EQMOD feature agenda, I understand, is a polar alignment utility that should allow most astro-imagers to forego drift alignments. Got any ideas of your own? EQMOD's developers are more than open to suggestions and are found constantly inhabiting the Yahoogroup devoted to the driver.

How was the mount mechanically? I gave the C8, "Celeste," a slap on her rear (sorry, girl) and she barely moved. It was almost as if Atlas were grinning—smirking—at me, “Rod, do you think I can’t handle a puny C8?!” Even with the tripod extended enough to bring the C8's eyepiece to a comfortable height for visual observing, vibrations caused by focusing died out in a second--if there were any vibrations at all.

Summing up…by the end of the first evening I was convinced the Atlas is a heck of a lot of mount for a heck of a few dollars. To really prove its worth, however, Atlas would have to show me he was up to the very difficult task of taking long exposure deep sky images. That was next evening, though.

After observing a goodly number of deep sky objects--off a list of 100 "best of the best" I am working on, perhaps as the basis of a new book project--the clock was creeping on toward three a.m. The night had been a long one due to the early sunset, and I was tired before I got going from the drive down and set up, so I was amazed to have made it so late. I reckon I was mesmerized by Atlas, purring like a big cat as he swung Celeste to target after target. Big Switch thrown, I was soon out to the car parked on the access road so as not to disturb my fellow observers, down the spooky lane of mossy old oaks, and back to Highway 19 and the motel.

Down the spooky lane of mossy oaks and back to town...
Do you have any idea what's on the cable at 3:30 a.m., muchachos? Whole lotta nothing. When I arrived back at the Holiday Inn I was still spun up, though, and needed to watch something. I rummaged around and pulled out a couple of DVD's from Sir Patrick Moore's The Sky at Night TV show (got them from his magazine), hooked the DVD player to the room TV, retrieved a bottle of Guiness, and hit the "play" button. I barely got through one episode before I was off to dreamland.

In the morning, I filled up on the Holiday Inn Express' biscuits and sausage gravy till I made myself sick (literally), and returned to the room to try to figure out how to make the endless day pass.

Despite my late, late (or early-early) evening, I had gotten up up not long after 8. I am used to rising at 4:30 to commute to work and just can't sleep-in long. Winter sunsets come early, however, thank God, so the wait for darkness was not intolerably long. I filled the day by writing, reading the latest issue of Sky & Telescope, and surfing Cloudy Nights and Astromart on the laptop. A late lunch/dinner at the neighboring Taco Bell, and it was finally time to think about heading back to the CAV.

Out there, I shot the breeze with a fellow astrophotographer, who, with his SBIG and his T-Point and his AstroPhysics mount, was way out of my humble league. He approved of my Atlas/C8 setup though, and especially my Canon 400D Rebel, opining that if your main interest is pretty pictures, there's really no reason to use anything other than a DSLR these days.

Be that as it may, I got my new Canon (purchased at the same time as the Atlas) set for its first astro-imaging run. Ran up EQMOD, aligned on the same stars as the previous night, removed the diagonal and visual back, and configured the scope and camera for prime focus imaging. To that end, I mounted the camera on the C8 behind the f/6.3 reducer/corrector by means of a T-ring on the camera and a standard SCT prime focus adapter on the scope.

Gotta connect all those above mentioned cords and widgets, of course, including the USB and shutter cables to the camera. Shutter cable? Current Canon DSLRs require you to have a remote release to do exposures longer than 30-seconds. The DSUSB box/cable I got from Shoestring Astronomy takes the place of that and allows my imaging software, Nebulosity, to expose for as long as desired. Neb lets me operate the Canon much as if it were an astronomical CCD camera.

There was the guide scope, too. For me that is a 66mm William Optics SD refractor. Which guide camera? At the moment I am using my Meade (original color) DSI. Since it doesn't have a guide output to allow me to connect it to the Atlas' auto-guide port, I use another Shoestring adapter cable, which runs from the computer's parallel port to the auto-guide port and provides standard ST-4 guide signals. The guiding software I am using is, as I mentioned above, Craig Stark's PHD Guiding. "PHD" stands for "push here dummy" in this case, and that is really what is.

I loaded Nebulosity, and then went back to EQMOD to slew the scope to the evening's target, M42, natch. It's big, it's colorful, and it is bright, perfect as a first subject for a new camera and mount. When EQMOD beeped, indicating the mount was on target, I set the exposure in Neb to 2-seconds and pushed the "frame and focus" button. Shortly, an out of focus something appeared on the laptop screen. I focused carefully, making the stars as small as I could make them, and then switched over to "fine focus" mode. Click on a star on Nebulosity's display, and it is zoomed in. By observing this blown-up star and the graphs Nebulosity provides, it is easy to attain perfect focus. Viewing the camera's images on a big laptop screen is much easier than squinting through the tiny, dim viewfinder of a DSLR.

Now for the guider. I lit off PHD, began looping 2-second exposures, and focused till the stars looked good and small. I hit "Stop," chose a likely looking star, and clicked the Guide button. PHD calibrated, moving the star in all four directions to gauge how the mount reacted. I was gratified the Atlas displayed little or no backlash in declination--my CG5 has a bunch. When it was done with the calibrating, PHD immediately and automatically started guiding. That's all there is to it, loop exposures, stop, guide. It really is "push here dummy."

Back to Nebulosity. I set up a series of 20 three-minute exposures, clicked the start button, and Neb began doing its thing. PHD was, as I could see when the first sub came up with nice, round stars, locked on. There was literally nothing for me to do while the exposure series was in progress. So, I wandered around, talking to/annoying my fellow observers, ducked into the Clubhouse to retrieve a Monster Energy Drink, and cooled my heels until, somewhat more than an hour later, the series was done.

My first astrophoto with the Atlas/EQMOD...
All the frames looked pretty good from what I could tell, but I took another set just to be sure. I wanted a nice M42 picture for the new book, so it was best to do plenty of "insurance" shots. I did note a couple of things as the second bunch was going. First, that I needed to buy some sort of cover for the camera's display screen. At times it would light up, and on the dark field it seemed searchlight bright. Second, my camera batteries worked fine. I had been warned to get a 12 volt or AC supply for the camera, that long exposures would run its battery down in a hurry. But I am cheap and didn't want yet another cable. I compromised and bought a second camera battery. The first battery lasted through the first set of subs easily, and might have made it through the second, but I inserted the second, fully charged one before proceeding just to be sure.

By the time my second M42 series finished, it was midnight. I was tempted to go on to a second target. B-u-t. There was the dreaded packing and drive in the morning. Even if I had wanted to go longer, Urania said "no" and closed down her sky soon after my last M42 sub-frame completed.

As is often the case this time of year at the CAV, ground fog was creeping in. I managed to shoot the last couple of frames through the fog, but ten or fifteen minutes after the last one finished, another wave of pea soup rolled in, covering the scope, blocking the sky, and causing me to pull the Big Switch. That's just the way the cookie crumbles. By the time I got back to the motel, it was well after 1 a.m., so, given the drive home in the morning, I was wise to quit when I did, fog or no fog.

At the Holiday Inn Express, I couldn't resist taking a quick peek at some of my subs. They looked darned good, even without processing. Most amazing thing? Nebulosity was wonderful. EQMOD was wonderful. The Atlas was wonderful. The Canon was wonderful. Most wonderful, however, was PHD Guiding. It just, yes, LOCKED ON. Still, I didn't realize just how good a job it had done for some time. Later, I discovered that, due to a peculiarity in my Atlas' particular motor control board, when you use the mount with EQMOD the RA speed needs to be adjusted slightly (in EQMOD) for correct tracking. I didn't know that and hadn't done that. PHD didn't care. It gave me round stars, anyway. Yeah, amazing.

I toasted Mr. Stark's amazing programs with a Guinness or two, watched a few minutes of the somewhat odd and very silly Ghost Hunters on the TV, and fell into a deep sleep ruminating on how preposterously cool it was that the new Atlas and all the other new gear and software worked perfectly the first time out. Sometimes you get lucky, muchachos, sometimes you just get lucky.


A dozen years down the road, what has changed? The Atlas was every bit as good a mount as I say it was here given its miniscule price. Unfortunately, it became too heavy for me as my 50s hit the rearview mirror.  The Atlas was sold--to a friend of mine, who I knew would give it plenty of time under the stars.  

Since I hadn't used the mount for a while, I gave it a good checkout before letting it go and it impressed me all over again. In fact, I wavered in my intention to sell it. Well, I did until I aggravated my back in the process of removing the mount from its tripod. If I could still handle a mount of this weight, I'd be hard put not to glom onto the new version of the Atlas, the EQ-R, which features belt drive and other improvements. Like the original, it yields a lot of performance for not many dineros.

The replacement for the Atlas I settled on was the Losmandy GM811G. Not only does it have higher imaging payload capacity, it's lighter than the Atlas, which is what is most important to me now. I considered the CEM60, which would likely have been fine, but I guess I wanted a change from the imported Chinese mounts I've used for so many years.

The 12 year old Canon 400D is still the camera I turn to frequently. In addition to its sensitivity (thanks to its relatively large pixels), I'm not reluctant to use it on dark and damp observing fields. If it gets dropped or otherwise irreparably damaged...well, it paid for itself a long time ago. And it's still capable of producing publication-quality deep sky images.

Chiefland, Chiefland, Chiefland. Sigh. I still miss it sometimes. Though I obviously didn't miss it enough to sign up for the recent Winter Star Party, which was held there this year. Might I be back? You never know. When I read an entry like this over again, it does make me a bit wistful and nostalgic for the good, old Billy Dodd Memorial Observing Field. 

Looking good, I guess I wasn't the only one who got an Atlas EQ-G for Christmas. Took the ole PowerStar 8 off the forks and as you say,it's like a rock now. The shoe string interface works just great. I only wish the skys would clear up here in Oregon, so I can use it. Thanks for the simple to follow alignment information.
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