NetNews Usenet Archive 1992 #19

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Path: sparky!uunet!wupost!sdd.hp.com!hplabs!ucbvax!nisc.sri.com!csl!ronnie From: ronnie@cisco.com (Ronnie B. Kon) Newsgroups: sci.astro Subject: Purchasing Amateur Telescopes FAQ (part 2/2) Message-ID: <1992Sep2.040110.28142@csl.sri.com> Date: 2 Sep 92 04:01:10 GMT Sender: news@csl.sri.com (NEWS Administrator) Organization: cisco Systems, Menlo Park, California, USA Lines: 872 X-Disclaimer: The views expressed in this message are those of an individual at SRI International, and do not necessarily reflect those of the company. Nntp-Posting-Host: lager.cisco.com Purchasing Amateur Telescopes FAQ Part II Ronnie B. Kon ronnie@cisco.com Last Updated: August 27, 1992 6. Buying A Telescope 6.1. What Company Makes the Best Telescopes? Hard to say, actually. The two biggest sellers are Celestron and Meade, both of which turn out good quality optics at fairly affordable prices. Disregard people who say things like "Well, Celestron's optics are better than Meade's" (they do have that reputation). The fact is that they are both quite good, and you probably will not notice a difference. Both do, however, occasionally turn out clunk- ers, which they will repair for free (as long as you are the original buyer). Televue has a very good reputation, at a somewhat higher price. Ques- tar has an excellent reputation, at an astronomical price. Coulter makes inexpensive Dobsonians, with acceptable optics. They offer the most aperture for the money, with several drawbacks. First, they are big. Think long and hard about how you are going to tran- sport it before deciding on the 10 inch or bigger. Second, they are basically deep-sky telescopes. All the Odyssey Dobsonians are short focal-ratio, which means they're picky about alignment errors. They all also have more than a trace of coma near the edge of the field (minor to unimportant nuisance for clusters, nebulae, and galaxies; a more serious one for planets and other small targets). Hence they're not as suited for high power planetary work as your basic, medium- sized refractor. The telescope is very basic; in particular no finder scope and the focuser is a bit on the rudimentary side--a simple fric- tion tube you pull in and out of the telescope's side. Third, they, like all Dobsonians, are altazimuth mounts: very stable but unsuited for astrophotography. Also, you usually have to order directly from Coulter and they're back ordered for six months or more on most of their telescopes. You can look for a dealer who could deliver quicker, for a bit more money (like $100). Tasco is sold at Toys R Us. You can build your own tripod out of Lego Blocks and have a mount of like quality to your optics. 6.2. How do Meade and Celestron Name Their Telescopes? Both in rather stupid ways, Celestron being stupider than Meade. Essentially, every Celestron Telescope is C-#, where the # is the size of the aperture in either inches or millimeters. Thus the C-90 is Celestron's 90mm spotting scope (a Maksutov-Cassegrain), the C-8 is their 8" Schmidt-Cassegrain, the C-6 is their 6" Newtonian. They will prefix these with "Super Polaris" to indicate the the telescope comes with their Super Polaris tripod and mount (a German Equatorial). Powerstar or PEC (for Periodic Error Correction) means it has their good drive (comparable to Meade's Smart Drive). Ultima means it comes with a heavier wedge and fork. Meade simply numbers everything. 2080 means an 8" Schmidt-Cassegrain. 2120 means a 10". Premier means sturdier wedge and tripod, and a better drive (but the same optics). All Premiers manufactured in the past year (but not necessarilly before) are equipped with "Smart Drive," which is essentially the same as Celestron's PEC. The Premier telescopes come with model numbers: 30 or 36 (no longer sold) means no hand controller, 40 or 46 means you get the hand controller, 50 or 56 means you get a declination drive (so the N/S buttons on the hand con- troller work) along with a slightly bigger finderscope and a 2" diago- nal, 70 or 76 means you get a whole bunch of stuff. If the number ends in a 0 (eg. 40) it is f/10. If the number ends in a 6 (eg. 46) it is f/6.3. If the number has an H postfixed to it (10" models only) it comes with the "superwedge," a heavier wedge that is more stable than the regular wedge, and is useful for astrophotography. The rest of their stuff is pretty obvious, if you stop and think: the DS-16 is a 16" reflector, for example. Meade has recently introduced the LX100 and LX200 series of tele- scopes. The LX refers to the drive (Meade has a very strange habit of changing what LX means--it used to refer to the drive, then (apparently) the focal ratio, now it's back to being the drive), which are certainly the most wiz-bang on the market. The LX200 has a com- puter driven declination drive, as well as the right ascension drive, which permits it to be used without an equatorial wedge. It can slew (move quickly across the sky) at the touch of a button on the hand control, you can hit the GOTO button to go directly to one of the 747 objects in it's library. You cannot do astrophotography on the Schmidt-Cassegrains without the equatorial wedge ($110 for the 8", $395 for the 10"). The LX100 does not have the declination drive, and so comes with a wedge, and doesn't seem to have most of the neat features of the LX200. 6.3. Comparison of Schmidt-Cassegrains To make selecting a Schmidt-Cassegrain somewhat easier, the following table summarizes the features on different models. Under the Make/Model column, a C indicates Celestron, a M is Meade. The tele- scopes that come without tripods (eg. 2045D, Classic 8, PEC-14) are priced with their recommended tripods. Fork is a fork mount, GEM is a German Equatorial. smart hand DEC motor computer Make/Model Speed Price Mount drive ctrlr drive focus control ------------------------------------------------------------------------------- C SP-8 f/10 $1050 GEM no no no no no M 2045D (4") f/10 $1050 fork no no no no no M 2080A f/10 $1140 fork no no no no no C SP-8 w/SB f/10 $1300 GEM no no no no no C Classic 8 f/10 $1450 fork no no no no no M 2120B 10" f/10 $1600 fork no no no no no M LX100 8" either $1700 fork yes yes no no no C PEC-8 f/10 $1800 fork yes yes no no no M 2080 #40 f/10 $1850 fork yes yes no no no M 2080 #50 f/10 $1850 fork yes yes yes no no M LX200 8" either $2000 fork yes yes yes no yes M 2080 #46 f/6.3 $2000 fork yes yes no no no M LX200 10" either $2300 fork yes yes yes no yes C Ultima 8 f/10 $2300 fork yes yes no ? no M 2080 #56 f/6.3 $2300 fork yes yes yes no no M 2120 #40 f/10 $2300 fork yes yes no no no M LX100 10" either $2400 fork yes yes no no no M 2120 #46 f/6.3 $2400 fork yes yes no no no C Compustar 8 f/10 $2800 fork ? yes yes ? yes M 2120 #50 f/10 ? fork yes yes yes no no M 2120 #56 f/6.3 ? fork yes yes yes no no M 2120 #50H f/10 $2900 fork yes yes yes no no M 2120 #56H f/6.3 $3000 fork yes yes yes no no C Ultima 11 f/10 $3500 fork yes yes no ? no M 2080 #70 f/10 ? fork yes yes yes yes no M 2080 #76 f/6.3 ? fork yes yes yes yes no M 2120 #70 f/10 ? fork yes yes yes yes no M 2120 #76 f/6.3 ? fork yes yes yes yes no C PEC-14 f/11 $6500 fork yes yes yes ? no C Compustar 14 f/11 $9700 fork ? yes yes ? yes M ? (16") f/11 $10000 fork yes yes yes yes yes 6.4. What Is The Best Telescope To Buy? Well, Meade has a 16" Schmidt-Cassegrain which is beautiful. It is portable (ie., you and a couple of friends can lug it), reasonably compact, and readily available. You can pick one up for about $10,000. If you are in a position to spend this kind of money on a first telescope (hey Wozniak: this is the one for you. Buy me one while you're at it) it would be a strong candidate. If money is an object, you will have to compromise. My recommendations, by price level, follow. Prices are given as a range, using the price from the cheap New York mail order companies as a low, and Orion or Lumicon as a high, where applicable. Bear in mind that you will need to have some money left over for extra eyepieces if nothing else. You will also find useful articles in the November 1991 issue of Astronomy (specs on a wide range of telescopes, and answers to a lot of the questions about technical jargon surrounding advertisers and equipment. There is also an article in the November 1991 issue of "Popular Astronomy." Both Astronomy and Sky and Telescope (especially the former) do review articles on telescopes, accessories, etc. on a fairly regular basis. Also, no FAQ list is going to be truly definitive--we all have our own opinions and interests, and one person's "piece-of-junk optics" might be another person's dream telecope. This does not apply to department store telescope, though. Really. Under $100 Get a pair of binoculars. The only telescopes in the double digit range are pure junk. On the other hand, you can get a good pair of binoculars. Orion sells a pair (the 7x50 or 10x50 Observer) for $85 specifically designed for astronomy. The Bush- nell "SportView" are a possibility as well. If you can spend a bit more, the Orion 8x56 Mini-Giant binoculars look like real winners ($150). On the other hand, for a further $50 you can buy the TeleVista (see below). Around $250 The Orion TeleVista 60mm altazimuth refractor ($200). Comes with a tripod, a finderscope, and a couple of Kellner eyepieces (a 25mm for 28x and a 9mm for 78x). These are .965" eyepieces, so you probably want to get the 1.25" adapter ($30 from Orion) when the time comes to buy new eyepieces. Odyssey 8" ($275). An 8" Dobsonian from Coulter Optical. Use- less for astrophotography, but far and away the most aperture for the money. The Orion 10x70 binoculars ($300). Personally, I would recommend going with a telescope before an expensive pair of binoculars, but enough people with a lot more observing experience than I have have suggested listing a high end pair. These are good ones. Under $500 The Orion SpaceProbe 4.5" Reflector ($399). A straight-forward Newtonian on a German Equatorial Mount, with cable controls so tracking right ascension should be easy. Most aperture for the money. Comes with a tripod and the same eyepieces as the Televista mentioned above. The Orion Sky Explorer 80 ($533). An 80mm equatorial refractor. Fairly sturdy tripod, and cable controls for right ascension and declination that should make it fairly easy to track stars without a drive. It comes with the same eyepieces as the TeleVista mentioned above. I don't know if I'd recommend the 60mm version of the above, which sells for $344, as it strikes me as simply the Televista on an equatorial mount. If you can afford the extra $200 on the mount, spring another $200 to get the 80mm objective (which gets 78% more light--a big difference). Edmunds Astroscan 2001 ($290 - $340). It is a very portable 4" Newtonian with the distinctive shape of a cylinder thrust into a sphere. The sphere rests in an aluminum base and the telescope can be pointed in any direction. Uses 1.25" diameter eyepieces. Supplied with a 28mm eyepiece giving 16x and a 3-degree field of view, wide enough to do without a finder scope. The drawbacks are that it is not very good for planets; and that it's difficult to track at high power. Also the "permanent collimation" the Astroscan comes with probably isn't. One respondent's seems to have come slightly out of alignment; this is unnoticeable at low power (e.g., the 16x it gives with the eyepiece it comes with), but is noticeable and rather objectionable at about 100x. Since it's permanently sealed up you can't go in and tweak the mirrors the way you can with most reflectors; you have to send it off to Edmund so they can look at it. Even if you could tweak it your- self, getting it all aligned would be tricky; short focal-length reflectors (which the Astroscan is an example of) are much more sensitive to minor alignment errors than longer ones. Accord- ingly, your high power images may be on the fuzzy side. Odyssey 10.1" ($345). A 10.1" Dobsonian from Coulter Optical. Useless for astrophotography, but far and away the most aperture for the money. Also the 13.1 inch ($575). Note that the 13.1 inch appears to be f/4.5, which means that the tube is almost 5 feet long. Think about how you will transport this before you buy it. The Celestron C-90 Spotting Scope with Multi-Coatings ($370 - $500). This is a catadioptric telescope with a 90mm objective. Note that due to the central obstruction, the C-90 has the equivalent light grasp of an 83mm refractor. The principle advantage is that it is compact and is very easy to carry around. The disadvantage is that it appears to be a telescope almost as an afterthought--the finderscope is pretty feeble, and you have to supply your own tripod. Probably the wrong choice unless you want to use it as a spotting scope in the daytime, or as a camera lens. Note that this last sentence is probably very controversial--many people that have the C-90 rave about it. Around $1000 The Celestron C-6 ($720 - $900), a 6" Newtonian. Comes on a solid German Equatorial Mount (the "Super Polaris"), and with an 18mm 1.25" Orthoscopic eyepiece (42x). The Celestron Super Polaris C-8 with Starbright Coatings ($1150 - $1300). This is an 8" Schmidt-Cassegrain system on the "Super Polaris" mount. It comes with an equatorial mount, and a drive which can track in right ascension. Note that you do not want the "Classic 8," which is the same optics in a fork mount but no tripod for $970 - $1250. The Meade 2080A ($915 - $1150). An 8" Schmidt-Cassegrain in a fork mount, with a decent tripod. Essentially comparable to the Super Polaris C-8. I'd suggest buying whichever is less expen- sive. Note that Meade is currently offering what they call a $600 package which includes three eyepieces and a Barlow (realis- tic value about $300) along with some useless stuff. This is scheduled to expire December 31, 1991, but they have already extended the deadline twice. The Celestron SP-C102 ($1050 - $1250). A 4" f/9.8 refractor (102mm) on the same "Super Polaris" mount as above. Takes 1.25" eyepieces (comes with a 26mm orthoscopic). Odyssey 17.5" ($1150). A 17.5" Dobsonian from Coulter Optical. Useless for astrophotography, but far and away the most aperture for the money. This appears to be f/4.5, which means that the tube is over 6.5 feet long. This will not fit into many cars. Make sure you will be able to transport this if you don't have a great observing sight at your house. Around $1500 The Meade 2120B (? - $1600). The cheapest 10" Schmidt-Cassegrain I could find, except for the 2120A, which appears to be the same 'scope, but without the coatings. The 2120A sells for $1500 from the discounters, so the B is almost certainly a better buy. The 2120B appears to be an f/10 scope with a fork mount. It comes with a tripod and a motor drive in right ascension. Presumably, no hand controller. (As you may have guessed, I've never seen one). All in all, a stripped down 'scope, but you get the aper- ture, which is the most important part of a telescope. Around $2000 The Meade 2120 model 40 ($2000 - $2150). A 10" f/10 Schmidt- Cassegrain system with "Smart Drive" and a hand controller (note that some early Premier models without Smart Drive are still available, usually for $100 - $200 less. Getting the Smart Drive is probably a good idea, as I suspect it will help the telescope's resale value if you ever need to sell. And it's a very expensive upgrade). The motor works in the Right Ascension direction but not declination (the declination motor costs extra). Do NOT opt for the super wedge. It costs about $300 extra, and can be bought separately (ie., later when you decide you actually could use it) for about $300. The same logic applies to all the nice things you get with the model 50--it costs as much to buy them packaged as to buy them individually. The model 30 would have been the winner, but Meade discontinued it (it was the same as the model 40 but without the $300 hand controller). The issue is that beginning astronomers do not need all the fancy equipment. You want the cheapest telescope that lets you look at stuff, and is upgradeable if you decide you want more later. The big disadvantage, which I did not appreciate until I bought this telescope, is that while the optical tube weighs only 45 pounds, it is unwieldy as hell in the case they give you. I find that I cannot maneuver it around corners in my house, so I either have to get my wife to help me, or I have to carry it by holding the forks, which do not give as good a pur- chase as one would like, given that one is holding a $2000 piece of very sensitive, and reasonably heavy, junk. It also takes up enough room in the back of the car that it won't fit if we are filling the car for a camping trip. I'm not yet sure how I will handle this, as camping is where I plan to use my telescope a lot. Around $2500 The TeleVue Genesis (? - $1600) and Systems Mount (? - $900). A 4" Fluorite Refractor, which many people rave about. The only disadvantage I can think of is that fluorite crystal is very moisture sensitive, so the whole thing could degrade. I have never used one, but it seems to me that it should have much less light grasp than the 10" Meade mentioned above (only about 1/6th as much). However, enough people swear by it that I suspect that it must make up for the smaller aperture in some other way; most likely in sharpness and contrast. On the other hand, given com- parable optics, a 10" telescope has 2.5 times better resolution than a 4". In any case, it is much smaller, and much more port- able than the 10" Meade. The Genesis II has been designed to fit into an airline overhead rack. The Meade 10" LX200 (Introductory price until 5/31/92: $2295). Tons of wiz-bang features (see above), for not a lot more than the Premier 2120s. The finder scope looks like the feeble one that came with my 2120/40, but you can certainly live with that for a while. Over $3000 This is well beyond my knowledge. I would recommend avoiding all the fully loaded and computer controlled versions of cheaper telescopes available at this price level. The fact is that you are a beginning astronomer and don't need all the fancy junk. If you have the money, look into a Star Fire refractor and a JMI NGT reflector. I have heard very good things about both, but never seen either. David Smith contributes the following about the NGT: I have spent a couple of evenings with an acquaintance who has an NGT-18. It is a very good scope. It's comparable in size to a Dobsonian, and I don't need a ladder to see into the eyepiece. I could see dim stars among the Trapezium which I couldn't see in other scopes nearby (4" refractors and 8-10" Newtonians and SC's). The rotating nosepiece works well, although it places increased demands on accuracy of physical and optical axes: the view was sharper from one rotation of the nosepiece than from another. Disadvantages of the NGT-18 are price, time to set up and take down, and lack of fine adjustments for polar alignment. 7. OK, Where Do I Buy My Telescope? Well, there are three basic places: A Store Yes, the obvious--you find a store (NOT a department store) which sells telescopes and write a check (or, if they won't give you a cash discount, use a credit card that offers buyer protection, or gives you bonus miles, or some such). The advantages of this method is that you have someplace to return the telescope to if you have problems with it. Some places even offer your money back if you change your mind within some grace period. The 'droids that work in the store may even attempt to offer some advice. My experience is that this is usu- ally 100% wrong, but that's actually as useful as advice which is always correct, but you have to know to invert the sense. The disadvantage is that you generally pay more for the telescope itself, and you pay sales tax. Mail Order There are two sorts of mail order: the discount stores that sell all sorts of stuff through the mail, and telescope stores that sell through the mail in addition to selling from their store. The advantages and disadvantages of mail order are obvious: you cannot take the merchandise back easily if something goes wrong, but it's cheaper (and you probably pay no sales tax). Other People You can find some great deals in used telescopes. Many people buy expensive telescopes, use them two or three times, get bored and sell them. The advantage is strictly monetary: you pay sig- nificantly less (and, of course, no tax). The disadvantage is that you are buying something "as is"--which you may want to think twice about doing if you are buying an expensive telescope. Also, both Meade and Celestron offer (lim- ited) lifetime warranties on their optics, which are not transferable. All that having been said, here is a list of places you can buy tele- scopes, with comments as applicable. Note that all will sell direct or will ship. Orion Telescopes 2450 17th Avenue Santa Cruz, CA 95061 (and two other locations) 800-447-1001 800-443-1001 in California Orion Telescopes carries a wide selection of binoculars, telescopes, and accessories. They also have a 30 day "no questions, satisfaction guaranteed" refund policy. The people who work there strike me as knowing very little about telescopes. In particular, they are almost entirely ignorant about Meade products, and seem largely indifferent about selling them. However, a number of people swear I am dead wrong: that the salespeople are very knowledgeable. I can only con- clude that I've been getting all the wrong salespeople. In any case, their products work, and they seem serious about their guarantee, which is the best I have ever seen. A fair number of people have said that they have bought at Orion and all are very satisfied with the way they were treated. This place is fairly expensive, and they have the sleazy policy of charging a "stocking fee" if you buy from the store, which always seems to be the same as the postage and handling fee for mail ordering from their catalogue. Lumicon Livermore, California (see S&T or Astronomy for Address) This is where I ended up buying my telescope. No complaints, but there really was no opportunity for anything to go wrong: I drove up knowing exactly what I wanted and what their price was, paid by credit card, and drove my new telescope home. And it is not all that impres- sive that they had it in stock--I bought one of the most popular tele- scopes around. Wholesale Optics of Pennsylvania (see S&T or Astronomy for Address) One respondent reports having no complaints in buying accessories from here. Kenneth Novak & Co. (see S&T or Astronomy for Address) One respondent reports having no complaints in buying accessories from here. University Optics (see S&T or Astronomy for Address) One respondent reports having no complaints in buying accessories from here. Adorama 42 West 18th Street New York, NY 10011 orders: (800) 223-2500 info: (212) 741-0052 Along with Focus Camera (see below), the lowest prices you will find. Expect no dealer support, and make sure you find out how much they will charge for shipping before placing your order. And pray that the optics arrive intact. I really would recommend that you not buy tele- scopes from these guys. Eyepieces and other accessories, however, are probably worth the risk if the price difference is significant. Focus Camera 4419-21 13th Avenue Brooklyn, NY 11219 orders: (800) 221-0828 info: (718) 436-1518 Refer to Adorama. Same comments apply. 7.1. What About Buying Used? Think long and hard before spending a lot of money on a used tele- scope. You will not have a warranty, and you have no assurance that the optics are in good shape. If you decide to buy used, get a sub- scription to The Starry Messenger, and look at their ads. Also check your local paper for classified ads selling telescopes--this is where you will find your best deals, as they are selling to the smallest audience. It appears that most people want to get about 75% of list when advertising in the astronomy rags (Starry Messenger, S&T, etc). This is probably not enough of a discount to make it worthwhile. If you can find something at 50% of list, you might want to think about it. You certainly want to see the telescope before you buy. A used tele- scope is just as good as a new one if it's been properly stored, tran- sported and used. A little dust on the optics is generally a sign of a telescope which hasn't been cleaned frequently, which is usually better than one which has. Get the issue of Astronomy magazine from around December 1990 (I don't remember the exact month) which had an article on star testing a telescope. If you don't live close to the seller, try to get someone from the net to go inspect the telescope for you. (You probably want to send them the money in this case and get them to ship it for you. This is a major imposition, please note, so you will probably have to do some serious begging to talk anyone into it, but it lessens the chance of fraud). 7.2. What About Building A Telescope? This section was written by Andy Michael. We just took a rather unusual approach to getting a beginning tele- scope: we took John Dobson's telescope building class and built an 8" and a 12.5" reflector on Dobsonian mounts (of course). We went this way for a few reasons: to get large aperture for seeing deep sky objects and higher magnification with good resolution when compared to small refractors in this price range, to keep the price down, and to soak up John's wit and wisdom. The down side is that these telescopes are not suited for astro-photography (at least not without building a different mount) but that didn't bother us. Also they are large. The 8" tube we broke into two pieces for easy portability, but the 12.5" one will probably go on the roof rack. These are about f/7 telescopes so the tube lengths are 56" and 7' respectively. Of course, when you build yours you can make whatever size you want. On the other hand you can pack your clothes in them; try that with an SCT. The cost was about $250 for the 8" telescope, $450 for the 12.5"er plus about 24 to 30 hours of work and 16 - 24 hours of class. It's a challenging pro- ject but the first time you focus on something with a mirror you ground is an incredible thrill. Another benefit is that we now know a lot about telescope design and if we ever have problems with them we know how to fix them. If you don't have access to John's (or other peoples') classes then you can try building one by reading his book and by watching the video. Our class was the first to see parts of the video and had great success at finishing the telescopes fast and without needing to correct the mirrors very much. Coincidence? Class consensus was no. The book (excerpted from the order form): "How and Why to Make a User-Friendly Sidewalk Telescope" by John Dobson with Norm Sperling. To appreciate why Dobson makes each factor just so, learn how he thinks about it. His philosophy of star-gazing perfuses his tele- scopes and his book. The book includes the only detailed biography; wonderful vignettes from the Sidewalk Astronomers' many expeditions; their own special way of describing celestial objects; and, of course, complete details for making a Dobsonian. 169 pages; 154 clear, friendly line drawings; 9 photos. Hardbound in plywood, Dobson's favorite material. Exclusive source. Send $39.95 + $5 shipping to Everything in the Universe, 5248 Lawton Avenue, Oakland, CA 94618. The video (also excerpted from the order form): For the first time on video, John Dobson shows how you can build your won low-cost Dobsonian Telescope. The 90-minute video is a complete step-by-step guide, cov- ering telescopes from 8 inches to 16 inches in diameter. Make check to "Dobson Astro-Initiatives" and mail to: Dobson Astro-Initiatives, P.O. Box 460915, San Francisco, CA 94146-0915. Form with your name and address has these choices: Rush my tape(s) as soon as available, I enclose $37.50 per tape for __ tapes. OR Please just let me know when the tapes are available (should be by the end of 1991). 8. What Accessories Will I Need? In addition to a telescope, you absolutely must have a mounting and a tripod. You will also need a few eyepieces--a telescope with only one eyepiece is like a piano with one key. These accessories don't come cheap--expect to pay as much for the mounting and tripod as you paid for the optical tube. For a first telescope, you probably will want to buy an entire system--it tends to be less expensive that way. It's also easier. Which eyepieces should you start with? I'd suggest three or four, maybe a 30mm, 25mm, 20mm, 8mm and a 2x Barlow (which will give you coverage of 30, 25, 20, 15, 12.5, 10, 8, and 4 mm). Buy eyepieces of like quality to your telescope. Putting a $300 Nagler eyepiece on a $150 telescope is pointless (it would also probably tip over the entire telescope). Buy accessories of like quality to your optics. 9. Why Should I Start With Binoculars? The quick answer is because you already have them, so you do not have to spend any money. Certainly going right out and buying the Fujinon 25x150 Astronomical Binocular ($11,000 list price) would be a pretty stupid thing to do, no matter how good the binoculars are. You should also avoid the quick-focus binoculars, as they are easy to de-focus as well. The remainder of this section was written by Paul Zander. Based on my experience, I suggest that you start with a pair of 7x50 binoculars. This is the most popular size and hence good ones are available from many stores, even some of the discounters. Be sure to get ones that have anti-reflection coatings on the mirrors and lenses. If you wear eyeglasses, you may be able to find binoculars which can focus without them (unless you have significant astigmatism). Make sure the image is sharp at the center and edges at the same time. "7x" is the magnification. Most people can hand hold these without needing to bother with tripods, etc. The "50" means 50mm (~2 inch) objectives (aperture). This gives light gathering ability similar to many small telescopes. Many advanced star gazers regularly use bino- culars to either locate items to focus telescopes on, or just for the wider field of view. When trying to view near the zenith, use a reclining lawn lounger: you can lie back and support your arms on the chair, giving a steadier view. You also will not get a crick in your neck. You might also use a plastic pad to lie on. 9.1. How Do I Hold Binoculars? This section was written by Jay Freeman. If you don't have a tripod (and tripods are sometimes a little clumsy, and are often difficult to use when the binocular is pointing near the zenith), it is important to know how to hold a binocular correctly to achieve maximum steadiness. The way most people tend to hold a binocular is with one hand on each side of the middle of the body--roughly where the prisms are in a con- ventional 7x50, say, so that the left hand is directly to the left of the center of gravity of the instrument and the right hand is directly opposite it, to the right of the center of gravity. For most people, there is a better position. Imagine that you are holding the binocular to your eyes, with your hands positioned as just described. Now, slide your hands along the body of the instrument, toward your face, until only your pinky and ring fingers are curled around the back end of the binocular body. In this position, the binocular feels a little nose-heavy, because you are supporting it behind its center of gravity. Now curl each thumb up as if you were making a fist, and flex your hands so that the second bone in from the tip of your thumbs are pressed up against your cheekbones (counting the bone in the part of your thumb where the thumbnail is, as the first bone). This makes a quite solid structural connection between the body of the binocular, through your hands and thumbs, to your face, and markedly improves how steadily you can hold the instrument. Similarly, curl the first and middle fingers of each hand around the corresponding binocular eye- piece, to provide a little more structural connection (and perhaps also some protection from stray light). In this position, your hands are not far from where they would be if you brought them to your face to block out stray reflections while peering through a store window at night. For most people, this position leads to markedly steadier viewing, but if the binocular is especially long and heavy (say, a 10x70 or an 11x80), the out-of-balance position can be quite tiring. In that case, move *one* hand out to the objective end of its side of the binocular, so that you are supporting the instrument on opposite sides of its center of gravity, but with some structural connection between it and your face; namely, the other hand. When the hand way out there gets tired--just switch hands. For each person, there is a limit to how heavy and / or how powerful a binocular can be, before there is no way for that person to hold it steady enough. I am an averaged-sized adult male in reasonable physi- cal condition, and I find I can hold a 10x70 (Orion's) steadily enough to use indefinitely on astronomical objects. But I have an old Celes- tron 11x80, that doesn't look much bigger or heavier than the 10x70, that I can only use for a few minutes before my arms get tired. As a 12-year old I am sure I could have used a 7x50 indefinitely with no problem, but at a younger age I might have had difficulty using one continuously. Your experience may vary with your strength, size and condition. Try before you buy, if at all possible. 10. What Books and Star Charts Are Recommended? If you don't know the constellations, you might want a book that will help you learn them. A "fun" book for those just learning the stars is The Stars, A New Way of Seeing Them by H. Rey, which presents a non-orthodox way of drawing the constellations so they are easier to visualize. You will probably want a beginner's guide, such as the book by Sherrod mentioned above. Sky Publishing has some introductory materials which would probably be as useful, which you get for free when you sub- scribe. Petersen's Field Guide to the Stars and Planets comes highly recom- mended. It is very inexpensive ($13), small and handy to use at the telescope. It has a good discussion about stars, planets, nebulae, and galaxies; and has a very complete albeit small-scale star chart, along with a the usual tables. It has long lists of deep-sky objects for each area of the sky. You will need a bigger star chart than is included in Petersen's. Try Sky Atlas 2000.0, by Wil Tirion. The field edition, which has white stars on a black field, is probably more useful than the desk guide. It is also printed on heavier paper, so is more resistant to dew and the rigors of the night. For beginners, buying Uranometria 2000.0 is probably a mistake. Yes, it is the "best" star chart, but the scale is impossibly small--when the Orion constellation takes up four separate pages it is really hard to use for beginners. Burnham's Celestial Handbook ($36). This three volume set is billed as "An Observer's Guide to the Universe Beyond the Solar System"--a rather all-encompassing claim, which it manages to live up to. Infor- mation on every item of interest you can think of: galaxies, double stars (optical and binary), variable stars, nebulae, etc. More infor- mation than you could use in a lifetime. I consider this a necessity. Sky and Telescope's 100 Best Deep Sky Objects. About $5, which is kind of expensive for a list, but it sure makes it easier to figure out what to look at when you are just beginning. The items are sorted by Right Ascension, which makes it real easy to figure out which ones are currently up. All the materials listed are available from: Sky Publishing Corporation P.O. Box 9111 Belmont, MA 02178-9918 USA Their catalog is free. Sky Publishing is the parent company of Sky & Telescope magazine. 10.1. What About Computer Programs? There are basically two types of astronomy programs: calculations of astronomical things and computerized star charts. I don't consider either of them worth buying as a tool to help an observer. On the other hand, some of them (particularly the star charts) can be a lot of fun to play with during the day or on cloudy nights. Before you buy any, you should probably check out the ones available on the net (see next section). For a good example of the variety of programs which will calculate things, look for Zephyr Software's ad in Sky and Telescope (or, presumably, Astronomy). They list two pages of programs, for about $60 each, which can calculate things like solar eclipses, or lunar phases, or ephemerides, etc. To my mind, your money would be better spent on eyepieces, or a bigger telescope to begin with. As for computerized star charts (usually $100 - $250), these can be very nice. Most will draw in the constellation lines if you like, will let you click a mouse on an object to have it identified, find objects by name, and so forth. Also, the fact that they can scroll the sky is much nicer than having to turn pages in a printed chart. The fact that they can show the sky as it is tonight, as opposed to a fixed time (such as 2000.0) is so pointless as to be laughable. The only problem is that you will probably never be able to use your com- puter at your telescope, which means that this is something you will use indoors. This strikes me as a nice recreation, but again, you would be better served by spending the money on a better telescope. As for recommendations for programs, both Dance of the Planets ($200), and The Sky 4.1 ($75 - $175, depending on the size of the database of objects) tend to get rave reviews in the magazines. Both are only for IBM PCs and compatibles. The former is available from A.R.C Science Simulation Software P.O. Box 19558 Loveland, CO 80539 (303) 667-1168 The latter is available from Software Bisque 912 12th St. Suite A Golden, CO 80401 (303) 278-4478 Brian Cuthbertson has a program HyperSKY, which he was kind enough to send me to review. Unfortunately, the first disk was corrupt, so I could not load it onto my computer. However, from the brief instruc- tion list he sent it appears to do what you would expect a computer- ized star chart to--zoom, pan, identify objects, is mouse-based, and so on. (Yes, I know that I don't have much here to base a review on, but: 1) he is on the net, and I admit to a net.bias; and 2) he said nice things about my FAQ and sent me a free copy of his program.) HyperSKY is available from Willman-Bell publishers (see add in any copy of S&T or Astronomy). A correspondent recommends the program Distant Suns as being a good computerized star chart, that was written by Mike Smithwick, who some- times reads this group. If Mike would care to contact me, I'll include price and address here. If he wants to send me a review copy, I'll even give my opinion. 10.1.1. What Programs Can I Get For Free? Well, I use a program called ephem, for calculating a whole lot of stuff (like ephemerides, phase (of moon and planets), dawn, dusk, etc. I have heard good reports about a program called 'starchart' and another called 'observe', the former prints out star charts, and the latter calculates where objects are, in a format accepted by 'star- chart.' All three are available from mandarin.mit.edu by anonymous ftp. You definitely want to get these before paying for anything else. For IBM PCs, there are a bunch of files at wuarchive.wustl.edu in /mirrors/msdos/education (descriptions are from the index): ASTRO20.ARC Calculate planetary ATA, rise and set time COSMOS14.ZIP Astronomy pgm displays skies viewed from earth EPHEM421.ZIP Astronomical ephemeris: stars/planets positions GRAVITY2.ZIP Simulates motions of planetary bodies in space MOON.ZIP Graphic display of moon's face w/pan/move/find SATVIEW2.ZIP Mathematical model of sunlit planet Saturn/CGA SFS0002.ARC Space flight simulator, CGA/HGC/EGA/VGA SKYGLO25.ZIP Skyglobe v2.5: Educational map of the sky SKYPLOT.ARC Star map graphic display SOLAR.ARC Solar system simulator STARVIEW.ARC Astronomy at its best - (requires mouse) -- ------------------------------------------------------------------------------- Ronnie B. Kon | "Boy, they were big on crematoriums, weren't they?" ronnie@cisco.com | (415) 688-4592 | -- George Bush at Auschwitz, Sept 1989