Sunday, May 22, 2011


Revenge of the Return of the Attack of the Go-to Wars!

I thought we were done with this, I really did. With what? The controversy about goto, about computerized telescopes. That has been a subject for discussion—often heated discussion—among amateurs since self-pointing scopes hit amateur astronomy in a big way nearly two decades ago. Yeah, I thought we were done, since amateurs have mostly voted with their feet, flocking to go-to rigs with wild abandon. It’s now rare to see a telescope without a computer, and if you include “push-to,” human-powered computer-guided scopes, in the tally, it’s clear the “war” is over and the old fashioned way, star-hopping, lost.

Or so I thought. Not long back the innocent (probably) question by a novice (probably) on a Cloudy Nights discussion board asking about the worthiness of go-to sparked dozens and dozens of posts, many condemning the computerized pointing of telescopes to the fires of perdition in the strongest terms. Well, the strongest terms permitted on the strait-laced Cloudy Nights. What do I think? Before we get to that, it might be a good idea to recall where we’ve been telescope computer-wise.

Goto as we know it is in large part the creation of a talented Arizona amateur astronomer, Mike Simmons. But he was just the man who put the final pieces of the puzzle together. Goto was something that evolved, not something that sprang forth full grown like my lady Athena from the forehead of big-daddy Zeus.

Professional telescopes have been using something like goto for many years. As far back as the early twentieth century, pro scopes have been operated from remote consoles, with the telescope operator watching dial indicators for right ascension and declination, slewing the scope till it arrived at the displayed coordinates. At first, these dials were not unlike ships’ heading repeaters—simple indicators run by synchros. This evolved into nixie tubes (lighted numbers), and, by the 1970s, real go-to came to the big scopes with the advent of the mini (not micro) computer.

Amateurs? Some creative individuals had been experimenting along these lines since the mid-sixties at least, and by a decade and a half later, remote-reading setting circles were commercially available with displays based on the (still new) L.E.D.s. These were the first digital setting circle systems, the first push-to systems. Which is not to say amateurs rushed to adopt this nascent computer technology. The early digital setting circles were expensive and weren’t very accurate. Oh, they could be accurate, but that required good polar alignment, good orthogonality between scope and mount, and good mechanical stability.

Still, many folks could see the potential was there and kept working on the problem. Before long various computer whiz kids had improved the pointing accuracy of the little marvels and even made them work on the alt-azimuth mounted Dobsonians that were now all the rage.

By the 1980s, a few folks were even dreaming of taking the computer-scope thing to the next level. Connect a digital setting circles computer to motors and you’d have a telescope that would point itself. A number of people were working on this idea, including the late, great Roger Tuthill, who'd demonstrated a go-to computer for a C8 at the 1979 Riverside Telescope Maker's Conference, but I didn't sit up and take notice till I read an article about Mike Simmons in Sky & Telescope for October of 1984.

The article, an installment of Roger Sinnott’s “Astronomical Computing,” regaled us with mind-blowing tales of Mr. Simmons’ triumphs, which included loading the entire NGC catalog into a 16k ROM chip and coupling a computer to a pair of stepper motors (probably refugees from a dot-matrix printer), which were then able to drive a telescope to dozens of objects (well, maybe; the demo the article reported on was done indoors in the Stellafane clubhouse). Mr. Sinnott even did a little skylarking, wondering if it might be possible to load Simmons’ gadget up with asteroid orbital elements or—shazam!—the position of Halley’s Comet.

Three decades of advances with telescopes and computers later, this seems tame to the point of silliness, but it was indeed mind-expanding back when most of us were still amazed by the Space Invaders video games displacing pinball machines at the mall arcade. No, Mike Simmons wasn’t the only person working on the goto scope idea, but he was one of the most advanced workers, and soon kicked things up several notches.

For the next couple of years, goto scopes remained the province of the computer gurus among us. There were several kits being marketed that would supposedly allow you to add automatic pointing to your mount, but those were, if not for gurus, at least for advanced mechanical and electronics tinkerers. But it wasn’t long before goto became commercially available for all of us. Well, at least for those of us with enough simoleons to pay a rather steep fare.

Not long after the Sky & Telescope article appeared, Mike Simmons began working with Celestron to produce the first commercially available amateur computer scope. An SCT, natch, the Celestron Compustar. Yes, Celestron was there years before Meade. So why aren’t there scads of used Compustars around?

Several reasons. Most critically, the telescopes were expensive, with the 8-inch model listing for a gobsmacking $6500.00. Even the heavily discounted price you’d get from your dealer amounted to at least $3500.00, more than twice what we were used to paying for top of the line CATs. The C11 and C14 models? Don’t ask.

There was also the question of performance. Oh, the Compustars worked, but were maybe not quite ready for prime time. Their pointing could be pretty good, but only if the scope’s polar alignment was pretty good, too, and even then you couldn’t expect perfection. That’s why the scopes shipped with 2-inch diagonals and 50mm eyepieces, so the Compustar would have a fighting chance of putting the object of your desire somewhere in the eyepiece field. The telescopes were also power hungry, and were more suited to permanent installations than portable operation. Ironically, it was at this time that more and more amateurs were beginning to need to travel to get to even semi-dark skies.

The Compustars’ cost and semi-finickiness when combined with Joe and Jane Amateur’s natural skepticism about computerized anything made the Compustar less than a hit, and while Celestron kept selling ‘em for dang near ten years, little further development was done and before long Mike Simmons and his project moved on to friendlier waters—Meade.

What did Meade do with the Simmons go-to system? They marketed it to rank and file amateurs. They did that by getting cost down and reliability up and, most of all, continuing to work on their “Compustar,” which they called the “LX200.”

What did we amateurs think of this amazing fork mount SCT, available in 8 and 10-inch apertures (initially)? We were easily as skeptical of it as we were of the Compustar. Yeah, it was much less expensive, the 8-inch coming in at around $2100.00 with a wedge, about what you’d pay for any other top CAT once you added all the “options” required to do much with it. But this damned thing claimed it would put any one of 747 deep sky objects in the eyepiece by itself. Old Unk, for one, needed to be convinced.

I was convinced. One cold winter’s night back in 1993, I headed to the Possum Swamp Astronomical Society’s dark site. So did a buddy, the then President of the PSAS, and he’d brought along his brand new telescope, one of those curious LX200s. I gotta say I was impressed by the way this 10-inch SCT looked with its lustrous Meade Blue tube and all, but, honestly, it didn’t look much different from Meade’s previous flagships, the LX5 and LX6. What was the big deal? Pretty soon that became obvious. I was startled out of my quiet contemplation of M78 by something that sounded like a coffee grinder on steroids.

That was, of course, the sound of the LX200 slewing to its target at full speed. Which didn’t sound very encouraging. Nevertheless, I was eager for a look, and when my pal offered me a peep at M42 I was at the eyepiece in a right quick hurry. Looked sweet. Nice, sharp, good contrast. Not better than an LX5, though, I thought. What was the big deal?

I found that out in short order when the SCT’s owner told me to take it for a spin, to “go-to” an object. A little instruction and I punched-in M79. The scope made its whining sounds, stopped, and when I looked in the eyepiece, there was M79 dead center. M15? Bang, there it was, looking good. NGC 7662? Same-same. Needless to say, I was bowled over. So, did I run out and buy an LX200? No.

I did need a new SCT, seeing as how I’d sold my so-so Celestron Super C8 Plus to help finance a divorce. But I hesitated. I’d always been a Celestron man, but there was more to it than that. A few months down the road, my buddy was having serious problems with his LX200, confirming my “unreliable” suspicions. It was only later that I found out he’d opened up the telescope and tinkered around in an effort to make “good” into “better.” I bought a Celestron Ultima C8, a traditional non-computer SCT, and didn’t worry about go-to anymore. For a while.

I used my Ultima 8 happily for years, imaging Hale-Bopp and lots of deep sky objects and doing mucho good visual work. I didn’t need no stinking computers. It sure looked like everybody else did, though. At every star party I went to, the field was more and more dominated by the sound of coffee being ground in quantity.

One evening at the Deep South Regional Star Gaze, I had the chance try Meade’s latest ETX for a couple of hours. The company had long since added go-to computers to its ETX Maksutov scopes, and was now expanding the line with some inexpensive refractors, including the one I was looking at with a jaundiced eye, the Meade ETX-60, a 60mm “short tube” refractor.

I figured this would be a joke. A plastic-bodied joke. How could you make go-to work for a couple of hundred bucks? I followed the simple instructions on the Autostar controller, aligned on two stars, and punched in “M15,” just like I had on that long ago night with the LX200. The little scope made the same coffee grinding sounds as its big sisters, stopped, and claimed it was on target. I looked in the eyepiece and guess what? There was M15 staring back. It looked small in the little refractor, but was right in the middle of the field. I probably viewed at least thirty more deep sky objects in the hours I had the helm of the ETX-60.

Upshot? I rushed out and bought an ETX-60 of my own right away. Details of my many adventures with “Snoopy” are the subject for another blog, but the little refractor gave me a lot of pleasure, went everywhere with me including Mount Pisgah in the Appalachians, and, most of all, got me in the go-to groove. It was obvious computer pointing for telescopes was now a mature and reliable technology. So much so that I began to think about a serious go-to rig.

That rig turned out to be a Celestron NexStar 11 GPS, Big Bertha. She was a success from day one and still is nearly ten years down the road. I soon realized I’d gone from being a star hopping skeptic to a goto fool, running my telescope with the aid of an omnipresent laptop, NexRemote, and SkyTools. Well, almost. Occasionally I’d begin to feel something like guilt and would go back to the Ultima 8. One DSRSG, I felt that strongly enough that I left Bertha at home and lugged the U8, Celeste, to the star party instead.

Big mistake that turned out to be. Sure, I enjoyed star hopping, but, unfortunately, many of the objects on my list were at northern declinations or near the zenith. If you’ve ever used a manual SCT on an equatorial wedge, you know what I am a-talking about. Looking at stuff in those areas is about as painful as it gets, with poor Unk either trying to squeeze his head between wedge and tube, or lying flat on his back. After three nights of that, I was flat stove up. There had to be something better than this!

There was. In fact, the solution was obvious. I loved Celeste’s OTA. Her optics were and are some of the best I’ve seen in a C8. What I would do would be to perform a forkectomy. Celeste would be deforked: I’d put her on a modern, computerized German equatorial mount. Which GEM? My choice of a Celestron CG5 is another thing that probably deserves a blog entry of its own, but I was and still am very happy with the little GEM. I know I have seen more, much more, in the seven years the U8 has been on the CG5 than I did the first seven years I owned the telescope.

So it is go-to all the way for me? Purty much. I still like star-hopping, locating objects with a finder scope or a zero power sight, once in a while. But it’s not something I do all the time or even occasionally. That guilt I felt? It has evaporated like the morning dew after an all night run with Bertha.

There is no need for guilt. The wonderful thing about amateur astronomy is that there are no rules. You are free to enjoy the night sky as you see fit. If that’s star-hopping with a Telrad, fine. If it’s letting the telescope do the work, great. Some people enjoy hunting deep sky objects; maybe even more than they enjoy the actual viewing of the DSOs they hunt. And that is cool, but doesn’t describe me. Not anymore.

I enjoyed decades of hunting, but as I enter my (shudder) sixth decade in amateur astronomy, my goal is to see as much of the Universe in as much detail as I can in the years remaining to me. Goto is letting me do that. I can still find obscure objects with atlas and finder, and sometimes exercise those muscles, but for me now it is the destinations I am interested in, not the journey.

The critics of computer-scopes? I answer them thusly:

If beginners start out with goto, they will not learn the stars and constellations.

Theoretically, that is possible and I agree it’s not such a good thing. Knowing the stars and star pictures helps a newbie develop a personal relationship with the sky and ensures, I think, that amateur astronomy will be a lifetime passion, not a passing fancy.

Used to be you had to know the stars even if you used a goto telescope. It would have to be aligned; you’d have to point it at a couple of known stars before the computer could take over. Today? Not so much. Things like Meade’s Lightbridge system and Celestron’s SkyAlign have made it possible to align a go-to telescope without knowing the names of any stars.

Not to worry. Even novices who use completely automatic goto systems learn the stars and constellations anyway. You cannot help learning ‘em if you spend a lot of time under the night sky. If you don’t want to spend a lot of time under the night sky? If astronomy is just a sometimes thing for you? The latest computer-scopes allow you to see some cool stuff anyway. It’s all good, muchachos.

Go-to users are more interested in going to many objects than they are in looking at them.

Nope. Not at all. Just the opposite. In my experience, go-to users are more passionate about the objects in the eyepiece than they are about the mechanics of finding said objects. When you don’t have to spend most of your time outside squinting through a finder and going back and forth between a star atlas, you have a lot more time to give each target due attention in the eyepiece.

Go-to telescopes are not reliable or accurate.

Hardly. Any electronic device, from PCs to TVs, can have problems, but today’s computer-scopes are amazingly reliable. I have (knock on wood) never had a single serious problem with my NS 11 or CG5 that wasn’t pilot error.

Modern rigs, even inexpensive ones, are also crazy accurate. My humble and inexpensive CG5, for example, will put anything I request from horizon to horizon somewhere in a .5-degree eyepiece field. Yes, you have to align the telescope properly, but that is not hard with a little practice.

You need a degree in computer science to run a go-to scope.

Let’s face it: some folks simply cannot get friendly with technology. These are the people who never could figure out how to program their VCRs. And yet…today’s goto telescopes are increasingly user friendly, and I have been able to get even the most computer-phobic going with goto with just a little instruction.

You are not an astronomer if you use goto.

So who is an astronomer, then? In my not so humble opinion, anybody who looks at the sky and wonders is an astronomer. If you want professional validation for your go-to rig, remember, professional observatories have been using goto forty years, and setting circles, mechanical or electrical, since at least the 19th century. The pros haven’t star-hopped for a hundred years.

So who wins? The goto fools or the star-hopping skeptics? Everybody wins. We can all do amateur astronomy just the way we want to. ‘Course, I don’t think anything I say is going stop the controversy, and, in a way, that is a good thing. It shows we are passionate about our avocation.

We don’t want to get carried away with that, though. As I’ve mentioned a time or two, amateur radio, our sister hobby, presents a cautionary tale. For amateur radio operators, hams, the requirement that all hams know Morse code, “CW,” was their star-hopping. The more farsighted hams believed this antique form of communication was justly obsolete and was keeping new people from entering the ranks, but old timers insisted that everybody had to pay their dues to be a ham. With the result that amateur radio nearly died. The code stumbling-block is gone now, but, sadly, ham radio hasn’t yet recovered and may never recover. Don’t let that be us, y’all.

You wrote:

“The wonderful thing about amateur astronomy is that there are no rules. You are free to enjoy the night sky as you see fit. If that’s star-hopping with a Telrad, fine. If it’s letting the telescope do the work, great.”

Amen to that! :-)
I used a regular GEM for years with my 1986 C8 but thought little about the Go-Tos until someone showed up at a public star party event asking for help with a telescope his wife bought him.

I downloaded all the Celestron owners' information and we worked on it in my driveway, but couldn't get it to align. Turned out it was defective. Still, I bought a CG-5GT and modified my old C8 to use on it. (It can be done, despite what I've read elsewhere).

It's worked fine and with the GPS it works even better. Good thing I learned the stars long ago. Did anyone see the piece in the New York Times about the new Celestron systems that take a picture of the sky and then align that way?
My first goto scope was a Meade LX90. I feared that I would not be taken seriously as a 'proper' astronomer. I observed more galaxies in one night with my LX90 than in the previous 20 years. Not going back!
My first goto scope was an LX90. I feared that I may not be taken seriously as a 'proper' astronomer. I observed more galaxies in one night than in the previous 20 years. Not going back!
"I was startled out of my quiet contemplation of M78 by something that sounded like a coffee grinder on steroids."

Well Meade accepted a little ribbing as I Photoshopped this and posted this on 4M:
You said:
"Things like Meade’s Lightbridge system and Celestron’s SkyAlign have made it possible to align a go-to telescope without knowing the names of any stars."

and "vsafuto" said:
"Did anyone see the piece in the New York Times about the new Celestron systems that take a picture of the sky and then align that way?"

I think you both meant Meade's "Lightswitch" LS series scopes, which have a small built-in camera for alignment.
Meade's "Lightbridge" is their truss-tube dobs.
Well...not really. Celestron has just released a camera-based go-to system similar to LightBridge, and SkyAlign, which allows you to align on stars (or planets or anything) without knowing their names has been around for some time. ;-)
I'm surprised and a little dismayed that some folks still hold a grudge against goto telescopes. Like you noted Rod, there are no rules in amateur astronomy but there are evidently still some people who feel that some advances in technology will "ruin the hobby".

Since goto scopes have been around for quite awhile now, one would think that if the hobby was going to be ruined it would be in bad shape by now and obviously it's not! I say this as a life long star hopper who has only used a goto scope a few times - it was fun! - and even though I don't use the technology very often I do admire it.

Howard Banich
Yes, I knew about Celestron's SkyAlign, although I didn't know they also now had a version of Meade's Lightswitch.

And once again, that's Light_switch_, not Light_bridge_. Meade's Lightbridge is just a simple, non-computerized, non-driven dob. The only electronics in it are the red-dot finder and battery-operated primary cooling fan.
When I was introduced to the hobby, it was with a guy who use RA/DEC to find everything. While at Mt. Pinos (near L.A.) there was a guy who setup next to us. He had a push to refractor.

We were looking for the saturn nebula and this guy asked for the NGC. He input it, moved the scope and there it was. My reaction was "if I get into this hobby, that's what I want".

Well 5 scopes in, all goto (or piggy back) and I'm still enjoying. Starting to think of an Obsession UC, but I still want tracking etc. so it's out of the price range.

Ruining the hobby? - nay, more and more people are interested in the hobby because they can look AT objects, not look FOR them.
I love my star hopping, but the GOTO revolution has opened up a whole new field to amateurs... I don't have GOTO in my observatory at the moment...but one day maybe.....

If Galileo was alive today I reckon he would be the first in the "GOTO" queue.

Thanks for posting this article I enjoyed it ...... Mark
There are many questions in and around Astronomy that can ultimately be answered definitively. "To go-to or not to go-to" is, unfortunately, not one of these. It cuts right to the heart of why each of us "does" astronomy.

The answer to this question is not as simple as it might seem ... in fact, it tends to differ at different times.

I know several "professional" astronomers who make their living from either the science of astronomy or the industries that support it or amatuer astronomy. For them, ie. many on the cutting edge of the science, the ability to puch the envelope is what counts (when in work mode) and, as such, go-to types of technology make sense. When they are in "relaxed-observing" mode ... ie. enjoying the heavens for their own sake, they would not be caught dead using go-to technology.

For myself, a rank amatuer, I generlly "do" astronomy mostly for personal enjoyment, almost as a form of meditation. I very much enjoy the "hunt" of star hopping ... not to say I am particularly good at it, but the joy I experience when I find a particularly obscure object, one that I have labored long to find, is extremely pleasant. And I find I experience a kind of "high" for some time. The big Dobs is ideal for this and I find I love it.

Lately, I have begun to enter the world of bargain-basement astrophotography. When I am in pursuing the heavens in this mode, I don't want to waste time on locating heavenly objects as there is so much else to keep track of and get working synchronously. When I am in this mode, the go-to and superior tracking technology of my CG5 is perfect (at least for my budget). I am not looking to produce award-winning photographs ... I am just interested in "capturing" and preserving a small piece of wat I can observe.

So n answer to the question of "to go-to or not to go-to", I have to answer a resounding "YES!".
how to do you modify a etx astro to a go to system i notice that the next stage up from mine has ports on the side of the fork to take a hand held controller. how do i get to this step. need help mike.
If you have the port for the hand control, you can add an Autostar controller and have go-to. If you don't have the port, it can't be upgraded to go-to. Sorry.
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