by Jay Freeman
On December 11, 2000, I exposed the central California coast to the prospect of rain, fire, deluge, conflagration, earthquake, plague, slug infestation, asteroid impact, invasion from zeta Reticuli, and premature entropy death of the universe, by taking delivery of an Astro-Physics 10-inch Maksutov-Cassegrain telescope. The approach of this instrument to official introduction has tantalized many amateur astronomers, and I hope my reports will be of interest. Yet high-end astronomy equipment is sometimes controversial, so I had better present such relevant humor as I have, before the shootin' starts. Therefore I shall first offer...
Jay Freeman's list of the ten best reasons to get a 10-inch Astro-Physics Maksutov, with footnotes. (Actually, the same reasons might suffice even if you got one that did not have footnotes...)
10) To settle a bet on whether the flagpole at Tranquillity Base is still standing.
9) White tubes require the least preparation before refinishing. (a)
8) It's easier to spell "Maksutov" than "Apochromat".
7) I needed a 10-gallon Wesson Oil container for leaky Christen triplets.
6) Who would have guessed the cure for refractorholism was worse than the disease?
5) Ordering provided a chance to ask Christine if she was the one Rich Neuschafer had named a telescope after.
4) The California water shortage requires heroic action.
3) At last, a telescope good enough to bear Refractor Red as finder. (b)
2) I really wanted a Stowaway and thought someone might trade.
1) Harvey needs a mate. (c)
Notes:
Seriously, you who know me might wonder whether I had any reason to possess such a telescope other than wanting to gloat -- not that wanting to gloat is necessarily a bad thing. After all, am I not the deep-sky weasel who keeps making comments about how "APERTURE WINS"? Yes I am, but there are a few other considerations.
First, our hobby is composed of many sub-hobbies, and most of us practice more than one. I certainly spend most of my amateur-astronomy time doing deep-sky work, yet I do occasionally look at solar-system objects -- that would be the Moon and the planets, for those of you who are also deep-sky observers. Sometimes I do so with pleasure, sometimes only to keep from going cold turkey on astro-photons during the weeks bracketing full Moon. If I am going to do that kind of work at all, I would like to equip myself to do it well, and though we seem to spend half eternity arguing about which telescopes are best, there is little doubt that Astro-Physics's offerings are on most people's short list of candidates for this kind of observing.
Second, there are non-solar-system objects for which high resolution is important. They include double stars and certain kinds of planetary nebulae.
Third -- and this point elaborates both of the first two -- where I observe, Harvey, my Celestron 14, is usually hit hard by atmospheric seeing. As I write these words, I have set the C-14 up nearly 100 times in the two and a half years since I recommissioned it, and only two of those nights have provided really first-rate seeing for a 14-inch aperture. Smaller telescopes at the same star parties have been hit less hard: High-end six- and seven-inch telescopes, such as the handful of large Astro-Physics refractors that are regulars, deliver most of their potential performance often. I was hoping that 10-inch aperture would offer a healthy resolution increase over these, which would be obtainable at the eyepiece much more often than is the performance that Harvey can deliver. (Harvey is a pretty good C-14, but not perfect. It wouldn't surprise me if a well-figured 10-inch, with a smaller fraction of its aperture obscured by the secondary, offered higher absolute performance for seeing certain kinds of detail, yet this paragraph has more to do with sensitivity to seeing than with absolute performance.)
Fourth, Astro-Physics appeared to have been working quite hard to address some of the problems of cool-down time that often restrict the performance of high-end amateur telescopes; that also is a consideration in achieving high resolution, and one which has jaundiced my opinion of large Maks ever since a Questar 12 showed up at Riverside one year, and had almost cooled down enough to use by three in the morning, or so it was reported by those few die-hards who were still awake. I later encountered a 9- or 10-inch Mak from Intes or Intes Micro in the field, and it also exhibited severe sloth in cool-down.
Fifth, though the 10-inch Maksutov optical tube assembly weighs more than the optical tube assembly (OTA) of my 6-inch f/8 Astro-Physics refractor (not much more, considering I have equipped the 6-inch with a 15-pound counterweight near the eyepiece, to reduce the eyepiece height variation while observing), nevertheless, I expect that the smaller tube length of the 10-inch will make it quicker and easier to set up than the 6-inch. Thus it may well be not only a better telescope for the kinds of things I use the 6-inch for, but also an easier one to use. I may well end up substituting it for the 6-inch entirely, and find that I use it more often and with better results.
Sixth, the 10-inch Maksutov should work well with the rest of my observing paraphernalia. Its OTA is smaller and lighter than the OTA of my C-14, so I can certainly expect to use it on the same Losmandy G-11, and its eyepiece should be at least as convenient.
In a mid-2000 thread on sci.astro.amateur, some folks expressed concern about the processes whereby one gets onto an Astro-Physics notification list and then gets notified of an opportunity to buy. Although I own two other telescopes with Astro-Physics optics, I bought them used: The 10-inch Maksutov was my first purchase directly from the company, and I had no idea what to expect or what to do. Furthermore, I went through the "join list and get notified" process long before the sci.astro.amateur discussion. Thus it is probably worth reporting my experiences.
I first learned of the 10-inch Maksutov in mid 1998. I think I heard about it in postings by the proprietor of Astro-Physics, Roland Christen, on sci.astro.amateur, though perhaps my information came from some other part of the rumor mill. I wrote to Astro-Physics in November, 1998, and expressed interest in becoming a customer for one. Roland responded promptly, saying there was only a small, informal list of interested persons, and that he would put me on it. An opportunity to order might follow in six months. No money changed hands then, of course, for it was not by any means certain that Astro-Physics would produce the product, much less what its price was going to be.
It took lots longer than six months. Occasionally, during the next year or so, I sent EMail asking what was what. Someone always replied promptly. Twice I took extended vacations, and in each case I advised Astro-Physics, that in case an opportunity to buy came up while I was away, that yes, I still wanted one. I didn't save the responses, but the general flavor was "thanks for telling us, not to worry."
The opportunity to place an order came in January, 2000, a year and two months after I had put my name on the list. The EMail arrived late on Friday, 21 January, after I had left for a weekend. I didn't get it till Sunday, but the window to buy extended through Tuesday, so no problem. The EMail advised that the first unit should be shipped in two or three months, and that others would shortly follow. The price was $9800 for a "bare" OTA, with a down payment of 50 percent requested then (in January). It was clear that bits and pieces, like tube rings and finder brackets, might have to be added to an order, later on.
I ordered without a second thought, even though $9800 is more than any three or four other OTAs that I have ever owned are worth, put together. To keep things in perspective, one could put an Astro-Physics 10-inch Maksutov *and* those three or four other OTAs in the Isuzu minivan that I bought to transport stuff for my hobby, and the van would still have cost more than all the telescopes inside it. Nobody who owns a late-model car should consider amateur astronomy an expensive hobby.
It was nearly a year till anything shipped. I sent occasional EMail, mostly to make sure I had not missed something, and monitored sci.astro.amateur and the Astro-Physics users' group for hints on what was happening. Roland was having diverse problems in getting things to come together -- subcontracted optics had to be re-worked, stuff came back from the coating company damaged or with inadequate coatings, and so on. I wasn't particularly worried, even though I had no personal experience with Astro-Physics to go on; what I *did* have was a large number of friends and observing acquaintances who *had* dealt with Astro-Physics, who said that the company made fine products that were worth waiting for, and dealt with their customers with great fairness. It would take a lot of personal experience with any manufacturer before I could reach such a conclusion first-hand, but I had confidence in what my friends had to say.
I did not mind letting Astro-Physics have the use of $4900 of my money for the extra time. The problems Roland reported are the kind of thing that drives up price a lot; I suspect I would have paid a lot more, an increase of greater than a year's interest on $4900, if the price had not been set until delivery time, or if I had waited for a later production run.
Anyway, I ended up getting a fine telescope, with many ingenious features and exquisite optical performance, but discussion of those matters will have to await subsequent parts of this review.
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