Sunday, June 19, 2011
The Big One
I’m sorta torn on this. The older I get, the more I come to appreciate the fun you can have with a small, good telescope. Given my crazy schedule and my laziness, my StarBlast, my Orange Tube C90, and my ETX 125 probably get used more than any other instrument around The Old Manse. Still, I am not immune to the charms of more-better-gooder by way of larger aperture.
So it was one spring Saturday morning in 1994. After nearly thirty years of using 8-inch and smaller telescopes, I was determined to kick it up a notch. What had caught my eye was Meade’s new ads for their amazingly low cost StarFinder Dobsonians. Yes, I was, then as now, SCT crazy, but I’d decided I did want BIGGER, and I was also, then as now, cheap. I had neither the desire nor the ability to put out the bucks required for a C14, a C11, or even a Meade 10-inch. I was just coming off a divorce and my finances were a complete and utter disaster.
The Meade StarFinders seemed the perfect solution. I’d had my head turned a time or two by the famous Coulter Odyssey Dobsonians, but their pedestrian optics and unfinished appearance turned me off. I was also turned off by their delivery times, which could be long: months and months and months. Surely Meade, the SCT guys, could get me a Dobbie quicker than that? I figgered I could probably buy a StarFinder off-the-shelf.
Where would I get one? Even nearly twenty years ago, we were blessed with an excellent assortment of honest, reliable astronomy dealers. Back in the sixties when I got started, there were some good folks too, but there were also plenty of snake oil merchants only too happy to separate you from your hard-earned dollars.
This time around, I chose Astronomics of Norman, Oklahoma. Why? I’d ordered from them before and gotten good service and they had a good reputation. Mostly, though, this time I chose them because they had Saturday hours. I’d been divorced for about a year and, to fill the long, empty hours, I tended to stay late at work, until long after the telephone order lines for the Astro-dealers shut down. No 24-hour World-Wide-Web ordering in them days, sprouts.
I dialed up Astronomics and spoke to a nice man. He offered good and bad news. The good was that for a small sum I could upgrade my 12.5-inch StarFinder Dobsonian to a “Deluxe Package,” which included a 50mm finder (the stock job was a too-small 30mm) and two extra eyepieces, a pair of Meade’s Modified Achromats (Kellners, in other words). I hadn’t heard much good about those oculars, but the upgrade price was well worth it just for the 50mm finder.
The bad news? My scope would be drop-shipped. It wouldn’t come from Astronomics, but directly from Meade, and the order-taker informed me that it might be “weeks” before I got my telescope. I was a little disappointed the Dob was not an off-the-shelf deal as I’d imagined, but “weeks” didn’t sound so bad. I was a little preoccupied at the moment, anyhow. That very Saturday night I had a date with this fascinating woman I’d just met, “Dorothy.”
That first humble date, a trip to the movies to see Shirley MacLaine and Nicholas Cage in Guarding Tess, followed by drinks afterward at a nearby Applebee’s, turned into a genuine and whirlwind romance. By the time summer of 1994 had begun to wind down, the wonderful Miss Dorothy and I had set a date and were getting married. That was what mostly occupied my thoughts, but occasionally I would wonder, “What the hell ever happened to that Meade scope I ordered?”
I’ve told this story more than once, but I hope you’ll indulge your silly old Uncle one more time. I just enjoy reliving those memorable days. The promised weeks turned into months, and nary a telescope did I see. I suppose I could have called Meade or Astronomics, but I was busy, even for busy old me, and I sorta forgot about the 12.5 SF for a while. I had had the presence of mind to tell the lovely Miss D. that I had ordered a new telescope, and that it would arrive “sometime soon,” but I’m not sure that fully registered with her.
At this point, I’m pretty sure Miss Dorothy was still under the mistaken impression that being an amateur astronomer meant you had a telescope, a rather small telescope, one telescope, that you took out into the backyard once in a while to look at the Moon and stars. Her education in the ways of the amateur astronomer began the day before our wedding.
I’ve also told the story of the assembly and modification of the StarFinder before, in some detail here. So I won’t go on and on about it. I will just say the front parlor was filled with huge empty cardboard boxes, tools, instruction sheets, and, most of all, telescope parts. When Dorothy walked in the door, I immediately chirped, “HONEY, IT CAME! IT CAME!”
If I hadn’t known what a wonderful person I was marrying, her reaction would have informed me as to that. I’m sure she must have been a little appalled at the chaos in her formerly orderly home, but there was no sign of it. What came out was happiness; how happy she was for me. That is one of the many reasons I love Miss Dorothy so much and have always loved her so much.
I was able to get the telescope assembled, and was pretty pleased with the results. But this is not specifically about my 12-inch Meade; it is about big scopes in general. If you’d like to read more about my adventures with Old Betsy, read the aforementioned entry. Anyhoo, the telescope was together, but Miss D. and I were immediately off on a two week honeymoon to the mountains and Civil War battlefields of North Carolina and Virginia, before I could find out how the biggest telescope of my life would perform.
A big scope is a heavy scope and can be a pain to move around…
When D. and I returned to begin wedded life together, and the skies finally cleared, sometime towards the end of September, the first challenge I faced was getting the big new scope into the backyard. I’d been worried about that since I got “Old Betsy”—as I immediately dubbed the telescope—together. Yeah, the 16-inch would have been like lugging a water heater around, but the 12-inch was like a small water heater, at least.
That was compounded with the fact that I stored the cotton-picking thing upstairs in the beginning. Yeah, I was comparatively young and stupid, but I had my reasons. I’d moved the Old Betsy to the second floor so she’d be out of the way for the wedding, and I figgered I’d better leave her there. I wanted to be very careful about cluttering up our home with my consarned junk. I didn’t know my Miss Dorothy. She was perfectly content for me to store my giant white Dobbie in the dining room; especially after I had a near disaster—for scope and self—one evening on the way down the stairs with the OTA.
The thing is, any Newtonian telescope larger than a 10-inch f/5, and any catadioptric telescope over 8-inches in aperture, and any refractor bigger than about a 5-inch f/6 will be large and bulky and heavy for many of us and needs to be as close to the backyard or other observing area as possible. There are dodges like wheels and handles, and be prepared to use ‘em. If you plan to haul your scope to dark sites, you’ll have to arrange the logistics for that as well.
A big scope will perform like a big scope…
After considerable huffing and puffing, even for a considerably younger Unk, my 12.5-inch f/4.8 was ready to go out back. Would more aperture really get Unk, who at the time did most of his observing from Chaos Manor South’s light-polluted backyard, much more than my convenient 8-inch did? From the first the answer to that was “yes.” The first light object was Jupiter, which was getting low in the west. Despite that, the planet was brighter at the magnifications I liked to use and I could see more. Much more.
How about the deep sky? I’d frequently heard an old wives’ tale concerning using big telescopes in light pollution. An old wives’ tale, yeah, but some of those old wives were pretty sharp: “It’s useless to observe with a larger aperture telescope from light pollution. The sky background will be so bright, the big mirror will take in so much more of that bad light, that you won’t see any more than you would in a small scope.” Well, M13 was well placed for observing; that ought to tell the tale.
One look put the nail in the coffin for those wives of yore. Yes, the field of the 12mm eyepiece was a little bright. But it didn’t look any brighter to me than it would have in my 8-inch at a comparable magnification, and there was one big difference. In my 8-inch, M13 was often a barely resolved blob in my poor sky. In the 12-inch it was a huge and beautiful ball of stars. Case closed.
All things being equal, aperture always wins. Especially in the city. If you must deal with light pollution, always use as much aperture as you can muster—you will see more.
A big scope needs high quality mechanics even more than high quality optics…
It was obvious, given its images of Jupiter, that my new Meade Newtonian had blow-you-away optics. But optics aren’t the whole story. A big scope needs blow-you-away mechanics, too. While Betsy was at least useable as she was, her mount was sticky in altitude and azimuth. The telescope used the same plastic and laminate bearings which worked well on the smaller StarFinders, but Betsy’s weight (sorry Bets) meant she needed better.
Meade’s corner-cutting by not using Ebony Star and Teflon saved them a dollar or two, but made for a worse telescope. As you’ll know if you read the above-linked blog entry about Betsy, I did the simple mods needed to get her in shape, but she was not really fully operational without those mods.
What works for a small scope may not work for a large one. Mechanical shortcuts that are merely annoying for a 6 or 8-inch can be debilitating for a 12 or 16-inch. There is a reason even Dob mounts are often big and comparatively heavy on big scopes: they must be.
A big scope needs great eyepieces…
Not that the other eyepieces in my collection, my treasured Celestron Silver Top Plössls, my Celestron-Vixen Orthoscopics, and a König or three, were much better. Oh, certainly they were OK, but not much more. The edges of their fields were passable, and I spent and spend most of my time looking at what’s in the center of the field, not the edge, but there was no denying these were not the perfect eyepieces I thought they were.
I was, in fact, not able to really see what the scope could do until that December when Miss Dorothy, now hip to the ways of the equipment-happy amateur astronomer, gave me a 12mm Nagler Type II for our first Christmas together. That showed me what is possible with a fast, big (for me) mirror and an optically excellent eyepiece. I still remember the glorious voyages I took through Virgo that spring, galaxy hopping through her deep, deep fields.
Almost all large Newtonian telescopes have fast, low focal ratio mirrors. To get maximum enjoyment from them, you need very good eyepieces and, faster than f/5, you will probably want a coma corrector. Restricting yourself to 50-degree AFOV eyepieces doesn’t allow these wide-field light buckets strut their stuff.
A big scope needs to be used…
AKA: “The best telescope is one that gets used a lot.” Only you can determine if you will use a large telescope often enough to make it “pay” for itself. If you’d like some detailed thoughts of mine along these lines, see this. Bottom line, though? It is a dicey thing.
Back in the beginning, when Betsy was in her Sonotube hot water heater body, I used her nearly every clear night. When, in the interest of fitting her in my Toyota, her optics were transplanted into a truss tube, it became rare for me to use her at home. To get her out the door I had to disassemble the truss. Previously, I could pick up the Sonotube in one piece, haul Betsy out back, and be ready to go in 10-minutes. On the other hand, my backyard viewing was eventually closed out by growing oaks (it is verboten to cut them down here in the Garden District) anyway, so if Bets weren’t a transportable truss tube scope, she’d never get used at all.
What’s practical for some folks may not be practical for you. B-U-T…it may be that even if you only get to use your bigun three or four times a year, she will still have been “worth it.” One look a year at M13 and one look a year at M42 with your large telescope may more than enough to justify the cash and the trouble.
Final thoughts? The older I get, the lazier I get. But there is no denying the allure of aperture. I sometimes try to convince myself that 6 or 8-inches is really more than enough—but that’s just making excuses. Well I know that you will see more and be able to do more with more mirror or lens. It’s possible to have fun with small aperture, sure, but at heart that is a compromise, no matter what you like to observe, even “just” the Moon. More is better.
At the moment, I have restricted myself to a C11. The realities of living at Chaos Manor South would seem to dictate that is the practical thing. But that doesn’t mean I have given up on the dreams of bigger. When things slow down a little for me, I can foresee a last telescope buy (yeah, I know, the next one is always the last one), maybe a nice C14. There isn’t much if any improvement in a 14 over an 11 for imaging—either with CCD cams or video cams—but one look through the eyepiece a big 14-inch, muchachos, and old Unk can’t avoid thinking, “Yeah, that’s it, THAT’S the name of the game.”
Next Time: Travels with Snoopy.
Well said belonging to the over 50 crowd my 'scopes have been getting smaller, I just don't have the umpth after a heavy day of work (FAA lab Engineering Group) to pull out the big one. My Questar 3.5 on Tri-stand and my Brandon 94 on a Quarter Hitch mount get the most use.
looking forward to the next entry your column is a must read on Sunday Mornings.
Gary (AKA Satman on Cloudy Nights Classic Telescopes Forum)
looking forward to the next entry your column is a must read on Sunday Mornings.
Gary (AKA Satman on Cloudy Nights Classic Telescopes Forum)
I rarely miss a week of Rod's blog. I've never been a CAT (or) a Newt kinda guy. I've been both from the start. When I retire, I plan to have a large DOB for visual and 14 for visual/imaging. Right now I have an 18 DOB and a 9.25 Edge HD. I plan to supplement them with an orion 10" F/5 for grab-n-go go star parties.Post a Comment