Rinky-Dink?

Fremont Peak 1997 June 28


Despite threatening daytime clouds over San Francisco Bay, the evening of Saturday, 28 June, 1997, brought the usual collection of telescopes to Fremont Peak State Park, near San Juan Bautista, California. I had my Intes six-inch f/10 Maksutov, and got intensively involved in a new observing program, so did not spend as much time as I might have wished with other telescopes.

In early 1997, I finished a long observing program, of all star clusters, galaxies, and nebulae in Burnham's _Celestial_Handbook_, north of 45 degrees south declination. I had been looking for new worlds to conquer. Recent experiences chasing down very faint galaxies with my six-inch Maksutov led me to believe that I could push on the faint-fuzzy limit without buying a new car big enough to haul my Celestron 14's trailer. So I found an on-line copy of the list of deep-sky objects discovered by William Herschel -- not the "400" list, I mean all 2514 -- at http://www.seds.org/billa/herschel/h2500.txt, and laboriously compared it against my own logbook and index cards. My not quite 3000 objects observed included about half the Herschel list: I decided to try for the rest.

June 28 was my second night on this program. During the first, last week in the hills above Palo Alto, I verified my previous experience that with an exit pupil of 1 or 2 mm, I can use the six-inch Intes effectively to chase down galaxies whose cataloged magnitudes are as faint as 14. The experience at Fremont Peak, with somewhat darker sky, added further confirmation. Visual magnitudes of galaxies are notoriously unreliable, so that fourteenth magnitude bit is not as impressive as it sounds. Still, it puts a lot of galaxies in range.

The main limit to using the six-inch for such dim objects is not so much detecting them as identifying them. Of the forty or fifty that I have looked for so far, at magnifications of 75 or 121, I have succeeded in detecting all but one or two. However, galaxies sometimes come in groups, and the averted vision, tube-jiggling, and other tricks of the trade for finding faint fuzzies, sometimes make it hard to separate two nearly adjoining blobs of lumpy darkness, or to tell one from another in a small cluster.

Fortunately, there are usually plenty of larger telescopes handy, and I have had excellent luck mooching time on them. One friend [see below] was very generous with his 12-inch LX200 on the 28th, not only for verification of things at my limit or for separation of things I could not, but also, just for fun, for whizzing through ten or fifteen on the list in less than half an hour.

Computer controlled telescopes are a big win for this kind of work. Let me not be modest: I am pretty good at star-hopping. Nevertheless, except perhaps in very dense areas where the distance from object to object is tiny, even the rather rinky-dink systems that Meade sells can find things several times faster than I can.

I do mean rinky-dink. The deformable-pad keyboard and no-feel joystick of the Meade control paddle make my teeth itch -- things haven't been this bad in the computer industry since the days of the late, unlamented Sinclair-Timex ZX-81. One virtue of the keyboard might be that it is watertight -- and as a friend pointed out, LX200 owners no doubt take great pride and relief in the knowledge that their telescopes will slew accurately and reliably, even when the rain is pouring down or the creek has risen. Setting accuracy is nothing to boast about, either -- for short slews the result is good to a few arc-minutes, but go across the sky and you will likely have to call up a nearby bright star, center it, and recalibrate. And of course, the Meade slewing motors make an atrocious racket, rather like the whir of a coffee grinder, or the call of a raccoon in heat.

Still, the computer-controlled Meade was fast, and my observing lists were binned by right ascension and sorted by declination, so most of the slews were small enough that calibration held. In consequence, the 12-inch, running at 150x or 250x, knocked off Herschel objects about as quickly as we could key in their NGC numbers. Rinky-dink or not, it was a reasonably-planned and workable system, and I was greatful for the opportunity to use it. Oh, well -- disposable earplugs are cheap enough to pass out free to bystanders, and I always bring a thermos of coffee to observing sessions anyway. I might be tempted to buy an LX200, if I could just figure out what to do about those raccoons.

-- Jay Freeman


Yes, it was great fun. Really. Went like this: Jay would call out a number, I would punch it up and peek in the eyepiece and see nothing. Then Jay would look and say "I see it just between..." and I would try again. About half the time I could detect something, maybe. (OK, once or twice there were a couple of easy ones, too.) Observing with Jay is a real learning experience!

[Re: my keypad], first of all, I agree. But to be fair, my keypad is worse than most (when the stupid covering over the real contacts comes partially unglued it has a horrible and uneven feel). And the joystick is an add-on. It is a simple mechanical rocker the just pushes the buttons underneath, so of course it has no feel. Still, I like it better than the buttons since at least I can tell which way to push it; with the buttons I was always hitting the wrong one.

It is possible to dispense with the keypad entirely and control the scope from a computer. But the keypad works well enough that I usually don't bother.

[Re: Setting accuracy] Again, to be fair to Meade, I was not carefully aligned. I don't usually bother to level my tripod. I'm usually happy if the object falls into the low power eyepiece field. Jay and I were using an eyepiece with only a 20 minute field, a hard case for sloppy alignment.

[Re: the noise] I won't offer any excuses on this point. Meade's design simply sucks in this respect. I was happy that there was another LX200 set up nearby so that I didn't have to bear the brunt off all the coffee grinder jokes. :*)

Many ingenious and knowledgeable LX200 owners have looked into this problem. So far no one has succeeded. The motors are integrated with the gearboxes and encoders. It would be a very big job to change them. And there doesn't seem to be much opportunity for noise damping/absorbtion. After awhile you get used to it :-(

-- Bill Arnett


Jay Reynolds Freeman / Bill Arnett); last updated: 1997 July 28