Sunday, May 26, 2013

 

A Celestron VX Comes to Chaos Manor South


Hokay, where was we, muchachos? Uncle Rod had just returned from the Deep South Regional Star Gaze Spring Scrimmage. I had bagged a passel of Herchels, well over 100, with my new OTA, Mrs. Emma Peel, a Celestron Edge 800 C8. The scope rode on my time honored CG5 for the star party, but awaiting me at home was what might possibly constitute the elusive more better gooder, Celestron’s replacement for the CG5, the VX German equatorial mount. It had arrived on Friday, day two of the star party, and Unk was itching to try it out.

As I told y’all last week, even though I arrived back at The Old Manse by early afternoon, I was tuckered out. I’d been up Sunday morning till after three shooting Herschels, and was back up before seven to pack. Twenty years ago, that was not a problem. Today? Takes me a while to shake off the star party aftereffects. I puttered around, returning most of the gear to its assigned places, took a long, hard look at the big box sitting in the front hall, and decided I’d be better off waiting till the morrow to open it.

Comes the dawn, Unk was up bright and early, you betcha, and after a cup or two of java to lubricate the ol’ mental gears, it was time to attack the VX. First order of business was dislodging Growltiger from his wonderful new sitting place, which was the VX’s box. After an entire weekend of enjoying his box, the striped cat was awful put out when I suggested he find another spot. All he did was give me a dirty look. What finally got him going was when Unk pulled out his knife and began cutting the box’s strapping. Growltiger did not like the sight of Unk armed with a knife and decided discretion was the better part of valor.

OK, let’s get this thing open. More slicing with Unk’s knife revealed—yet another box. Wisely, Celestron had double-boxed the VX, since the container holds not just the GEM mount head, but an 11-pound counterweight and the whole tripod. Inside, everything was in good shape. Step One would be getting the tripod together so I’d have something to mount the VX on.

The tripod, in its own slender box, was soon extracted. It was well protected with Styrofoam inserts at either end and the whole shebang was covered with a plastic bag. I did note the Styrofoam at the head end of the tripod had been broken into two pieces thanks to the tender mercies of the Brown Truck Guys, no doubt. There was no damage, and I soon had the tripod standing on its own in Chaos Manor South’s front parlor.

If you own an Atlas or a CG5, this tripod is going to be awful familiar. The VX tripod is identical save for the peg on the tripod head. This peg, which gives the GEM head azimuth adjusters something to push against, has been redesigned and repositioned. It is covered with a layer of plastic, unlike the old bare metal peg, and is located on the outer periphery of the tripod head. The manual now gives instructions for repositioning it “over” a tripod leg instead of “between” two if’n you feel the need. Supposedly, with it between legs, the tripod might be less than stable, but I’ve never had that problem with a C8 payload and left it alone.

Otherwise? The tripod spreader/accessory tray is the same. The 2-inch steel legs and the locks for their leg extensions are the same. The tripod tips are the same. The hand control holder is the same (as on the CG5). If you’ve never owned one of Synta’s standard field tripods, all I can say is that this is the best inexpensive tripod I have ever used and is more than adequate for a GEM in the VX—or even Atlas—class.

Rubber meets road: get VX head on tripod. The GEM head, sans counterweight bar, was nestled in its own box in a foam cutout, the whole thing protected with a layer of thick foam. With some trepidation, I mounted the head on the tripod, threading the central rod up into the hole on the head’s base. This is where I’d run into trouble with my original VX—the hole was not properly threaded. On this one, it threaded-in easy, same as my CG5 and Atlas and all was well.

The only major assembly that remained was installing the declination counterweight bar. As with the CG5, you thread the rod into the dec housing and secure it with the large nut. The counterweight bar on the VX is not the same as the one on the CG5. It’s the same diameter (larger than on the Atlas), but it is longer, five inches longer, 14-inches instead of 9-inches. This makes packing more of a pain but balancing easier. A C8 will balance on the VX with a single 11-pound weight with adjustment to spare. On my CG5, it takes two weights.

The counterweight itself? Yes, it’s an 11-pounder, but otherwise it is completely different from the standard Synta pancake weights we all know and love. It is of a much more modern shape, has a large easy to manipulate t-handle setscrew knob, and, in a real fillip, Synta has protected the end of that screw/bolt with Nylon so you don’t mar the mount’s counterweight bar.

It was now time to examine the hand control, which was well padded in its own package. The HC shipped with this mount is Celestron’s new version, the NexStar Plus, which brings both good and bad. The good is that it has more memory, a faster processor, and a higher resolution display.

The “bad” in the opinion of this old boy (and Thomas Aquinas, “Tommy,” Chaos Manor South’s resident black cat, who didn’t seem impressed) is that the buttons have been rearranged and relabeled to make them more “user friendly.” Famous last words, those. Not only do we now, confusingly for old-timers, have “Back” instead of “Undo,” the wonderful “M” and “NGC” buttons are gone. Now, you have to wade through a menu to get to Messiers and NGCs. A Celestron symbol key has been added that supposedly functions like a “shift” or “Ctrl” key, but I’m not sure what it is good for at this time—if anything.

Finally, I noted the hand control cord is ridiculously short. Contrary to what you may have heard on the dadblamed Cloudy Nights BBS, though, it’s only an inch or so shorter than the (still too short) cable of the original model. All this is really of little consequence to me, since I will likely operate the mount with NexRemote almost all the time, just like I do the CG5.

HC plugged in, that left only two things in the big box, the manual and the accessories. I did refer to the manual during assembly, but VX assembly is purty much identical to that of a CG5, so a quick look or two was sufficient. I’ve never seen a good manual from any telescope maker, but the VX manual is an improvement, at least. If nothing else, it now includes the instructions for doing an AllStar polar alignment the CG5 book lacked. Since NexRemote is now distributed freely on Celestron’s website, there was no NR DVD in the package. There was one containing the basic “First Light” edition of TheSky X.

How is that program? I like it a lot; in fact it has replaced Stellarium as the “quick what’s up look” program at Chaos Manor South. Actually, I probably like it better than I would the Professional edition of TheSky X. I’m not likely switch from SkyTools and Deep Sky Planner for serious work, after all.

That left the accessory box, which was in one piece, but had taken a bit of a beating from the counterweight container, I suppose. Inside was an HC holder for the tripod, a computer interface cable (first time I’ve found one in the box with a Celestron-branded mount or scope), the declination cable, and a 12vdc power cord.

The HC holder is the same as the CG5’s. It snaps onto a tripod leg and does a good job. There’s a hole in the bottom to pass a serial cable through to connect to the HC. Nice, and always has been. The coiled declination motor cable is similar to the one for the CG5. I’d like to have seen the dec connection routed internally, but at least the VX’s cord is shorter and less likely to snag on sumpin. Have to have a way to power the mount, of course, and the method Celestron provides for the stock VX is a 12-volt DC cable with a cigarette lighter plug on the end.

The 12vdc cord is, like all other Celestron 12vdc cords, excessively long. I suppose they think you will plug into your vehicle’s ciggie lighter. I urge you not to do that at a dark site unless you want to be stranded. The CG5 was purty dadgum power hungry, anyway. At least the cable is of heavier gauge wire than the CG5 power cord. One other change is that there is now a threaded collar à la the CGEM on the scope-end plug.

That’s it unless you choose to buy options. I have no use for a GPS receiver since I mostly use NexRemote and NexGPS, so I didn’t pony up for that. I did buy an AC power supply. I like to run on mains current down Chiefland way. The supply for the VX (and CGEM, I believe) is a nice one that looks like a laptop power brick rather than one of the old-timey wall warts. According to its label, it can furnish the VX with five amps of juice, which is more than enough.

New mount assembled, the next thing I always do is a “fake” alignment inside the house to make sure everything works more-or-less like it should. Before we do that, howsomeever, let’s take a closer look at the VX’s GEM head.

As you-all can see, this is not a gussied up CG5; it’s been redesigned. The RA housing is much more modern looking, considerably better finished, and appears stronger. The plastic RA motor cover is more attractive, much smaller, and less likely to snag a cable. Same goes for the declination motor, which, unlike the one on the CG5, does not rotate with the declination axis, a big help in reducing the chance of snagging cables or rubbing on another part of the mount.  A small but important improvement is that the RA and declination index markers are a million times easier to see in the dark than the pitiful labels on the older mount.

I never had much trouble with the altitude and azimuth adjusters on the CG5, but they did have small and hard to grasp knobs or were just bolts with minimalist handles. The VX is mucho different, troops. Big knobs for the azimuth adjusters and the rear elevation bolt, and a large T-handle for the forward elevation (locking) bolt. The design of the VX allows you to tilt the head down for latitudes well below 30-degrees, a problem with the CG5. Bigger knobs are also a feature of the bolts that hold the OTA in the mount’s saddle. The CG5 had one bolt and one safety screw. The VX has two bolts with large knobs, larger than those on the Atlas EQ-6.

The VX control panel has also been completely redesigned. It is now horizontal, protruding from the RA housing east side, rather than vertical and on the motor housing as with the CG5. The declination port has been moved from the control panel per se, and is on the right side of the control panel housing facing up. There is now less chance of the dec cable interfering with anything and much less chance of plugging the declination into the wrong port as Unk has been known to do. The connections on the panel are, from left to right, “Auto Guide,” “HC,” “Aux 1,” and “Aux 2.” There’s a large but not offensively bright red LED pilot light, and, wonder of wonders, an adult-sized power switch that looks like it, unlike the CG5’s tiny, pathetic one, might last a while.

The VX’s RA/Dec assembly, like that of any German equatorial, has to ride on a base that allows it to be tilted up and down and turned side-to-side for polar alignment, and the one on the VX is not only more modern looking than the CG5’s, it is obviously sturdier. I don’t have much use for a latitude scale, but the orange anodized one on this mount shore is purty. It’s easy to read, too, with a black scale and numbers that stand out well against the orange. The elevation axle is luverly:  it is, like the latitude scale, finished in orange anodizing.

Minor details? Guess what the CG5 has that the VX does not? Setting circles. It’s not like anybody ever used ‘em. Oh, and that “falls off if you look at it sideways” cover for the rear of the RA housing? It’s been replaced with a nice molded screw-on job. Finally, the forward cover for the polar bore now has a Celestron symbol molded into it.

Big Milestone One time: fake alignment. Tommy and I plugged the power cord into the mount. The thread-on collar is nice, but we also took the precaution of gently spreading the pin halves on the mount-side power connector a wee bit with a jeweler’s screwdriver—ain’t never seen a Celestron other than the NS11 that didn’t need that—and powered her up.

After a short pause while the HC computer thought about this or that, the backlight came on, and from there it was a two star alignment as per normal. Well, almost. The higher resolution display on the HC has smaller characters that are hard for my late middle-aged eyes to read. Apparently, you can adjust the font size, but I ain’t tried that. I entered time, date, and location like always. Only potential difference there is that, like the CGEM, the VX has an onboard Real Time Clock that, if turned on, will keep date/time updated. Unk shall probably leave it off since I will mostly use NexRemote, which uses the PC’s date and time.

I told Miss HC to begin a 2-star alignment, and things proceeded as they always do. I just pressed “Enter” and “Align” when the mount stopped. I said she could forget Calibration stars, and told her to go-to “M002.” Yes, it was annoying to have to drill down one menu level to the Messiers, but she went right to the general area where TheSky X said M2 ort ta be. Success.

I know the question you little rascals are itching to ask:  “Unk, how loud are the motors compared to them screaming Mimis on the CG5?” You can hear for yourself. I filmed a video of the fake go-to and put it on my cotton-picking Facebook page, but suffice to say they are noticeably quieter than the notoriously loud CG5 motors, if maybe not as quiet as the Atlas EQ-6’s steppers (like the CG5, the VX uses servo motors).

The only true test of any piece of astronomy gear is in its natural habitat, an observing field under the stars. I planned to do that this past Saturday night at the Possum Swamp Astronomical Society dark site. Maybe. The weather forecasts had looked iffy for a day or two, and on Saturday morning, when Miss D. and I were off to Mobicon, The Swamp’s yearly comic book/SF/anime/gaming convention, they were sounding worse. Whatev. Lot of hours till darkness, and we would see what we would see. Amazingly, at 6 p.m. the sky did not look that bad. Unk loaded up the 4Runner, but only minimally so:  mount head, tripod, Edge 800 OTA, accessory box, utility box, eyepiece case, cupla jump-start batteries.

The hour’s drive to the PSAS dark site was not unpleasant—when I didn’t look at the sky, that is. The farther west I got, the more clouds I saw. Still, when I arrived on the field at seven it didn’t look awful. A beautiful crescent Moon was riding high, so I would be all by my lonesome this evening, but that was OK. Given the conditions, my only goal was to align the scope and do a few go-tos to verify its proper operation. One sweet thing about buying an update to the C8 and an update to the CG5? It didn’t take me any longer than normal to get the mount and OTA ready to go. Just a few minutes and it was time to get my new finder aligned.

As I mentioned to y’all last time, the design of the Edge 800’s finder mount makes it prone to misalignment when you remove finder and ring mount from the tube for storage. I don’t much like 50mm finders anyhow. I sure don’t need one on a go-to rig; it is much easier to hit alignment stars with a zero-power (unit power) finder like a Telrad.

Now, I love the Telrad, you-all, but I must admit it does look a mite big and clunky and I didn’t think one would look too classy on my beautiful Edge C8, Mrs. Emma Peel. She deserved something more elegant, I thought. But something as functional as the Telrad. That, I decided, was the Rigel Quickfinder. An “upright” style, red-reticle rig. It’s smaller than the Telrad, and the base looks OK secured to the tube with double-sided tape. I ordered my Quickfinder from one of my fave astro-merchants, Agena Astro Products, who got it to me in time for the Saturday tests.

Pointed the scope at the windsock at the far end of the airfield runway and soon had the Quickfinder aligned with my 16mm Zhumell and, after that, with the 12mm Meade reticle eyepiece I use for alignments. I noticed almost immediately that the mount was easy to work with unpowered. The C8 stayed where I pointed it much better than it did with the kinda springy CG5.

Finder aligned, I looked up, and was not exactly thrilled with what I was seeing. More clouds. Darker, thicker clouds. I had intended to do a normal alignment, but I wasn’t sure the sky was gonna last that long—it wasn’t yet dark enough to see alignment stars. How about a Solar System Alignment, then? I fired up the mount, selected “Solar System Alignment,” specified “Moon,” and the mount was off for Luna.

She stopped surprisingly close to our satellite—the VX was not even roughly polar aligned, just pointed more or less north with my compass. I centered Diana up and hit align. Before doing anything else, I wanted a good look at the pretty crescent. In my el cheapo 16mm Zhumell 100-degree AFOV eyepiece, she was beautiful. Dead sharp almost to the very edge of the field. As I said last time, the Edge optics almost make the sow’s ear Zhumell into a silk purse Ethos. But not quite. I removed the Zhumell, inserted the 13mm Ethos (154x), and dern near had my socks blown off. The terminator was tack-sharp from one field edge to the other.

I sent the mount to Jupiter, and while the planet was close, it wasn’t in the eyepiece. Which was what I expected. I really needed to do a Two-star to assure myself about how well the mount would work. Looking north, I saw Polaris was in the clear, so I lined up the hollow polar bore of the VX on the star while waiting for a little more clearing. Those big altitude and azimuth adjusters were indeed a joy to use.

So, I waited and I waited. Just as I was about to give up hope, there was a sudden semi-clearing at astronomical twilight. I judged there might be just enough stars visible to do a real alignment. I cycled the mount’s power, returned it to the index marks, selected “Two-star” and away we went.

The first star, Capella, was close but not in the finder reticle’s middle circle when the slew stopped. I centered her up, and the mount headed for star two, Procyon. Very interesting. This time the star was in the center circle of the finder. It was not in the eyepiece field (45-degree apparent field at 166x). But dang close. Next were Calibration stars. I did all four because I could, but I sure didn’t have to. Cal Star 2, Mizar (I’d had to reject Spica, which was cloud-covered), was in the eyepiece field when the mount stopped. So were stars 3, and 4. The CG5 has never done this well. Not at f/10, anyway, for god’s sake.

Not only was the VX’s go-to accurate—as slews to Jupiter and M35 showed—at f/10, she was quiet, seeming even quieter than she had in the front parlor, if not little-mouse-quiet. The only question in my mind now was “What shall we look at, Mrs. Peel?” The answer, alas, was “Not much.”

The night was steadily growing worse, with my new iPhone app, Scope Nights, now saying the remainder of it would be “poor.” One more trip to the Moon, which was smack in the center of the 13mm, and I was ready to shut down—and not just because clouds were now pouring in from the southwest.

“What was the problem, Unk? Come on, now…did you get spooked again?” Maybe I felt a little nervous on the dark field as the clouds began to close in and make the night blacker than the inside of Thomas Aquinas, but it wasn’t the Mothman, the Little Grey Dudes from Zeta Reticuli II, and the Skunk Ape that got me loading the gear in a hurry. It was the little monsters. The skeeters. I thought I had a can of Deep Woods Off in the utility box, but I did not and I was simply being eaten alive. I was quite happy to be rolling back to Chaos Manor South with Miss Van Pelt’s air-conditioner blasting. The bugs are back and so is the humid Possum Swamp heat. Summer is here well ahead of Memorial Day.

Back in the den, watching the pea-picking Ghost Adventures and enjoying a dose of Unk’s favorite beverage, I was a happy and relieved little camper, muchchos. Yes, go-to as implemented by Celestron is pretty foolproof (ahem) these days. But you never do know. I told a buddy I’d be happy if the VX worked as well as the time-proven CG5. The verdict after Saturday night is “better than the CG5.” Maybe considerably better. I think this is the beginning of a beautiful friendship. I have a Chiefland trip planned in a month or two, and I should know even more about the new scope and mount combo after that. Y’all stay tuned.

In addition to the video, you can see many more pictures of the VX unboxing on Unk’s Facebook Page.

Next Time: What this Country Needs is a Good Five Cent Cigar… 

Comments:
Congratulations on the new scope, Uncle Rod. A nice modern take on the 8" go-to SCT!
 
Just a question. You seem to get a lot of new equipment. Do you buy these scopes and cameras, or or are they given to you by S&T advertisers because of your association with the magazine?
 
I wouldn't say I get a lot of new equipment 'round here. What I do get is paid for by my banker, not S&T. ;-)
 
Let me add that while I do not usually answer questions about business, personal business, affair related topics like "Anonymous" asks, I thought it was important to answer this one, since a lot of folks have come odd ideas about the astronomy writing biz. ;-)


 
Finally, a relationship such as Mr. Anonymous posits would be UNETHICAL in the extreme. That is not the way we roll at Sky and Telescope, despite ridiculous stories that make the rounds. "Sky and Telescope never gives bad reviews to advertisers," being a particularly ridiculous and easily disproved one.

Soapbox mode off. Excelsior, y'all! :-)
 
Hmm, i may just have to look into one of these EQ mounts next year. I do very much love my CPC1100, but my back seems to have lodged a Formal Union Protest against its 65lb weight of late. So no star watching for me for a few months. When i start up again, an EQ-mounted SCT + mallincam might be just what the doctor ordered...

-Mad Hungarian
 
Thank you for an interesting and informative review. The out-of-box experience is something many people want to know about.

I am considering buying a new telescope and mount. I have a Celestron C-8 that dates back to the Halley madness of 1986, and a CG-5GT mount that I bought a few years ago. I've gotten great use out of both, and am considering a VX mount with either a 9.25-inch or 11-inch Celestron tube.

I don't think the VX can handle an 11-inch, but do you think it can handle a 9.25-inch?

Thanks.

--VFS in Florida
 
HI Vinny:

The CG5 handles an 11 OK for visual use, and the VX should be slightly better. But, yes, the sweet spot, especially if you want to do imaging is a C8. I would also think a 9.25 would be just fine. For me, though, the 8 is my scope of choice day in and day out. When I need more, I go to the C11. Never been tempted by the 9.25...
 
You say in your article that the VX seems significantly better than the CG5 in goto accuracy. Could some of that difference be due to the upgrade to the hand control - Nexstar+ ?

Thanks
Don
 
I am not willing to say its go-to accuracy is better--not yet. I haven't been able to do much real testing due to weather. Its behavior seemed better...but we will see (the CG5 is pretty accurate itself). I would suspect mechanical reasons if it is better. The same code/HC is being used on CG5s, and I haven't heard anybody report better accuracy. Stay tuned... ;-)
 
Hi, I have a question. With this mount, and a DSLR attached to a refractor 4" OTA, unguided, how long can someone expose? I was told that the longest you can expose is like 90 seconds. If true, it sounds like you can't do much imaging with this. 90 seconds is quite short. So, do you have any experience or knowledge on this? Thanks.
 
Well, Mehmet, you can do plenty of imaging, but it must be guided if you want to go over shorter exposures. On the other hand, the same is true for much more expensive mounts like the Losmandy G11. If you need long exposures, you need to guide. BUT...I have produced excellent deep sky images with this mount by stacking 30-second unguided exposures. It can do plenty of imaging. :-)
 
Enjoyed your review of this setup in Sky and Telescope. I bought a similar setup back in May. As you point out, it hits a "sweet spot" for price, performance, and portability. It's the right telescope for those of us who are advanced astronomers but need to limit the cost, the bulk of the equipment, or both. As was the Criterion RV-6 forty years ago. Would it be too much to call this the RV-6 of a new generation?
 
Thanks, Mike!
 
Uncle Rod:
MANY THANKS for your review of the Celestron VX mount. I must say that Celestron customer service is about as helpful as balls on an armadillo (by the way never shoot an armadillo, the bullets bounce off) but I digress.
I found the supplied manual confusing with several important omissions. I have been an amateur and ATM since the early 70s plus an EO engineer in aerospace for 26 years so I'm not dumb.
I bought 12 of the 6 -inch Nexstar scopes while teaching at a local JC and had trouble getting the mount to align and track (let alone teaching college students how to do it).
I enjoy your columns very much. If you are ever out west (I have a house and observatory in Joshua Tree, CA. you are welcome to visit . We serve wine and beer to our guests, sorry no corn liquor,
Thanks

Paul L. Livio
Joshua Tree, CA .
 
Fortunately, these days a glass or two of red wine is about all I can handle...LOL
 
Do you have any advice on containers for storage and transporting the mount?


 
Visit Walmart, Adda, or a similar discount department store and have a look at their plastic storage ("Rubbermaid") containers. It may be necessary to remove the counterweight bar, but one can work well.
 
Hi rod, can I use the avx at 13 degree latitude? Can I remove the front latitude adjustment bolts?
 
You can remove it, but you may not have to.
 
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