Telescope Reviews

• Celestron Celestar 8
• Meade #226 60 mm refractor
• Unitron 3" f/16 equatorial refractor
• Carton 60 mm f/7 refractor
• Vixen 80 mm f/15 refractor
• Meade 12" LX200 (Brief Impression)
• Coulter 13.1" Dobsonian
• Meade 102ACHR/500 Refractor
• Sky Designs 24" Dobsonian
• TeleVue Oracle 3

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  1) Celestron Celestar 8 (8" f/10 Schmidt-Cassegrain, DC RA drive, 6X30 finder, 25 mm SMA, $1200) A good all-purpose Schmidt-Cassegrain, similar in style and function to Meade's LX10. The sample I saw had very well-corrected optics, but was slightly out of collimation. This resulted in some oblong stars at high magnification (ie, while trying to split Algeiba and Castor). A Good All-Purpose Scope: The Celestar 8 So, should you buy a Celestar 8 or an 8" LX10? There are a few differences. The LX10 comes with dual axis drives and a hand-corrector; the Celestron has an RA motor only (no controller). Celestron's forks and its combination wedge/ tripod look beefier than Meade's, but I didn't notice any stability differences between them. The Celestron has a nice shelf for your eyepieces under the wedge. I thought that the RA and Declination locks and slo-mo controls were a little smoother on the Meade. The height of Celestron's tripod is a matter of some debate. Some feel it's too short. I'm a little on the short side myself (5' 5") and it didn't bother me. Keep in mind that any equatorial fork mount is going to be a bit of a nuisance near the celestial pole. These C8 models do work well on Super Polaris class mounts; consider getting one. Finally, there's the weight. The LX10 weighs 49 lbs, while the Celestar tips the scales at only 37 lbs. This may be a factor if you plan to travel with the scope a lot. Both the LX10 and the Celestar are recommended for general observing. 2) Meade #226 60 mm refractor (60 mm f/11.66 refractor, OTA only, .965 25 mm MA, 5X24 finder, $? NLA) Fairly typical of entry-level refractors, these older blue-tubed Meade units show up occassionally through close-out catalogs like Damark. The finder scope is ridiculous; it has a field stop that narrows the aperture to around 7 mm. Forget it and just sight along the tube. The optics are pretty well corrected, although spherical and chromatic aberrations are there for the seeing. We used it on my cheap equatorial mount and split Algeiba and Castor, and the Orion Nebula was glimpsed, with 4 stars visible in the Trapezium. If you're new to astronomy and get one of these as a gift, you could do worse. How- ever, you will get bored with it quickly. Use it up, see all you can with it, then move on. Replaced by the model #227 in 1994, and the #230 in 1996. 3) Unitron 3" f/16 equatorial refractor (3" f/16 equatorial refractor, no drives, 1" f.l. eyepiece, NLA, new model $1995) Time stands still for Unitron, whose refractors haven't changed much in nearly 50 years Prized by hobbyists for their durability, solidity, and conservative designs, the Unitron refractor line remains unique. Indeed, the world in which telescope manufacturers try to out-do each other to see who can create the shortest focal ratio using the most exotic materials seems to have passed Unitron by. The sample I saw was a late 1950's model, but could easily have passed for a 1998 version (they haven't changed much). The 3" f/16 (not f/15, mind you, but f/16) tube is long, and has the identical focal length (48") of a traditional 6" f/8 Newtonian. The scope is well-built. I could not find a single plastic part on the telescope or mount. It's all metal and solid wood. The massive RA gear is silky smooth. And the focuser has no side-play whatsoever, even fully extended. Everything about this telescope tells you that its maker expected you to keep it for a long, long time. The diagonal is a spring-compression type. It was built long before Naglers existed, so we had to be careful with our heavy eyepieces. The 1" f.l. eyepiece supplied is nice, but modern eyepieces will put it away in short order. Finally, everything came packed in two heavy-duty wooden cases. Unfortunately, the sturdy mount is a real pain to assemble. Two of us working on it felt as if we needed five arms between us to put it together. What's worse, the ultra-high (non-height adjustable) tripod is built in such a way that you have to break it down and re-assemble it out in the field. I strongly suggest using a different mount, if you wind up with one of these. So, how did it perform optically? We set it up next to my 20 year old 6" f/8 Meade and the 4" Takahashi. The Unitron's objective was very well-corrected for chromatic and spherical aberrations. I could detect almost no false color, even at high power. There was a trace of astigmatism. Epsilon Bootes was split, as were Algeiba and Castor. The splits were all clean, although the 3" objective lens produces rather large airy disks (Castor at high power looked like 2 small planets sailing through the field of view.) Nice as these views were, the FS102's were brighter, more contrasty, and had that magic "snap" to the images that one associates with a modern apochromat. Looking at the objective lenses in daylight, the Unitron's was somewhat reflective, with a bluish tint on one surface. You could see a good image of yourself. Looking at the Takahashi in comparison was like looking down a black hole. The 6" reflector's images were even brighter, and the splits were even wider. However, the images were a little soft and "unclean" looking in comparison. The new version of this scope sells for $1995. This is somewhat expensive, but remember that you're only going to have to buy ONE of these. If you love planetary, double star and lunar observing, consider making a permanent spot in your home for a Unitron telescope. 4) Carton 60 mm f/7 refractor (OTA only, $?) Another "cute-scope". It's about the size of a TeleVue Ranger, but lighter. It is white aluminum, with a dark blue .965" visual back. There's a dovetail mount that looks as though it will accept the Orion Short-Tube's finder. The focuser has huge knobs and is very smooth. I attached my own 1.25" visual back and went observing. From suburban skies, I caught all of the Messier Virgo Cluster except M88, M89, and M91. Most of these were very dim, but they were within reach. "Fancy" eyepieces like Naglers and Panoptics seemed to bother the little scope, soaking up too much light. As such, I stayed with Plossls. Nice as it was, the Carton was significantly outclassed by the Ranger, which seems to have a lot more than its theoretical 36% light-gathering advantage. The Ranger is a Serious Telescope; the Carton borders on being a toy. If you want one, I am not sure you can get Carton scopes in the U.S. The larger Cartons, by the way, have an excellent reputation and are quite expensive. 5) Vixen 80 mm f/15 refractor The 80 mm Vixen, aboard a driven Super Polaris Available second-hand, these OTA's were sold under the Vixen name. Orion's older 80 mm Sky Explorer appears to be the same scope -- someone out there correct me if I'm wrong. The Vixen exhibited almost no false color, which helps explain why f/15 was such a popular focal ratio in years' past. The star test showed some moderate astigmatism. Also, on deep sky at higher powers, images began to break down (stars became halos.) In short, a competent planetary/double star scope. I found I preferred the images through the Unitron (above), however. New versions of this scope, sold under the Celestron name, are f/11. 6) Meade 12" LX200 (Brief Impression) (12" f/10 Schmidt Cassegrain, 8X50 finder, drives, computer, 26 mm Plossl, tripod, 2" focuser and diagonal, $3995 net total + $215 shipping) A great telescope. Not for purists. Although it's much larger than the 10" LX200, it doesn't appear to take much more time to set up or break down -- the parts are just heavier. The field tripod is massive, and appears to be the same one supplied with the LXD750 APO mounts. Unlike most scopes, where the drives and computers are little more than an after- thought, the computer is designed as an integral part of Meade's LX200 series (i.e. it is virtually impossible to operate the scope without the electronics turned on.) Operating Alt-Az, you simply point the scope at one or two known stars, and the scope takes over from there. And what a computer it is. Want to look at the Siamese Twins? Hit the "CNGC" key, type in "4-5-6-7", "Enter", and "Goto", and there you are. What fun! Actually, the computer is a necessity with a scope like this, due to its 3000 mm focal length (you wind up using lots of low power 2" eyepieces) and its Alt-Az mounting. I shudder to think what would happen if the electronics were to break down. The optics showed up minor spherical aberration, but at least the secondary was perfectly centered. I've seen a lot worse in a mass-produced Schmidt-Cassegrain. The scope was stunning on globular clusters. M13, M3, and M5 were completely resolved to the core. In fact, while playing with the focuser, it was easy to imagine oneself traveling through the globular, layer by layer. The dark dust lanes in M51 an M104 were also easily resolved. A great scope, provided you have the finances and the means to carry it around! 7) Coulter 13.1" f/4.5 Dobsonian ($799.99 new from Coulter, model tested NLA) Let's gather some light, Bubba! (Note 3/10/00: The newest versions of this scope are sold by Murnaghan Instruments. They are also red-tubed, and are said to feature a number of significant mechanical and optical improvements. I haven't seen one yet.) First, the bad news: The optics are loaded with coma. Astigmatism is visible even when the stars are "in focus." The azimuth bearings are too tight, and the rocker box, made of cheap chip-board, looks as if it's going to disintigrate at any moment. The good news? Who cares! It's a Coulter!! The name "Coulter" is synonymous with cheap, large telescopes; the company is generally credited with starting the modern Dobsonian revolution. Coulter buyers know what they're getting into, and don't expect cutting-edge optical design. In Coulter's heyday (the early 1980's), customers could choose between the 10.1" ($299), the 13.1" ($499), a 17.5" ($1195), and a goliath 29" ($3495). What's more, if you account for inflation, the prices for these scopes during the past 15 years have pretty much stood still. These telescopes will never be considered heirlooms, but Coulter doesn't exactly help its cause, either. For example, in late 1995, customers sending $395 to the company could buy the "Odyssey 8 Combo," which consisted of the rocker box, a 27 mm eyepiece, and TWO 8" optical tube assemblies -- an f/4.5 and an f/8 unit. And regarding that 27 mm eyepiece. Well...let's just say that I'm curious as to how many surplus binoculars gave their lives to the Coulter company. The model tested here is one of the red-tube "Coulter" units. The early Coulter models were blue-tubed, and were squared-off on the lower half of their tubes. The blue-tube units had a horrible mirror cell, just a piece of rope that held the mirror in place like a sling. You had to insert and remove the mirror before and after every observing session. A newer series, with a red tube (not squared-off) appeared some time later. The red-tube units had a permanent (even adjustable!) mirror cell, but the focuser was just a piece of plumbing with a locking ring. This "focuser" drove me mad as I tried to focus M13 in my 7 mm Nagler. In any case, these scopes are a lot of fun. You adopt a different attitude when using a cheap Dob (while loading this unit outside, we accidently banged the tube on the side of the door, scaping off some of the red paint. Neither of us cared, or even looked to see the damage.) If looking through a modern apochromatic refractor is like drinking fine, aged wine, using a Coulter is like grabbing a freshly-tapped keg and tipping the open spigot towards your opened mouth. Recommended (burp.) 8) Meade 102ACHR/500 Refractor (4" f/9 achromat, LXD500 mount, no drives or polar scope, 6X30 finder, 25 mm Series 3000 Plossl, $995 + $55 shipping) (No Longer Available) Gorgeous telescope. Meade has again succeeded in creating a beautiful piece of industrial design. This is not one of Meade's USA-built scopes; this one says "Manufactured in Taiwan ROC to Meade Specifications." This scope was tested side-by-side with the 13.1" Coulter (above.) First of all, the mount seems to be a half-cousin of the ubiquitous Cheap Taiwanese Equatorial Mount (see Various Eyepiece Review, Part 2, elsewhere) that's springing up everywhere these days. Like the others I've seen, there's some undesirable play in the equatorial head. Also, there is some unpleasant pre-travel in the slo-mo controls. The dew shield is attached using only one bolt (this curious one-bolt arrangement also appears on Meade's flagship 178ED), causing it to sag a bit even when attached. Also, the supplied 6X30 finder would not focus at infinity. The scope has chromatic aberration. There is a purple halo on even moderately bright objects. Targets like Vega or the limb of the moon have considerable false color (while using a 4.8 mm Nagler on Vega, for example, the entire field of view is purple-colored.) To be fair, the chromatic aberration is unavoidable at f/9. This is one of the fastest 4" achromats on the market today (Celestron's C102 operated at f/9.8.) On deep sky, images appeared razor-sharp compared to the Coulter, above. You definitely know you're looking through a refractor. The optics show excellent spherical correction. In addition, the scope's contrast was impressive. While splitting close doubles, however, I found the mechanical slop in the mount annoying. Update, 7/98: This scope developed a rattle inside its lens cell. Upon further inspection, it was discovered that the lens elements were loose inside the cell. What's worse, the retaining ring was screwed down so tight that it couldn't be loosened, even by the dealer. The dealer contacted Meade, who promptly sent out a new OTA. However, upon inspection of the new OTA, it too had rattling lenses inside its cell. Using the push-pull screws, the lens was aligned and re-tested. Unlike the original lens, this new one exhibits some spherical aberration. The objective shows up some rather extreme overcorrection - the in and out focus patterns are worse than the "1.7 wave error" diagrams on page 183 of Suiter's book. Again, Meade was contacted. They apologized for the poor OTA and agreed to send out a third unit right away. The third OTA arrived, and it too had loose lens elements, but it wasn't as bad as the other two. Unfortunately, this third tube had severe astigmatism, and was undercorrected by about 3/4 wave to boot. Add this to the chromatic aberration, and its images were unacceptable, even at low power. In many ways, this third OTA is the worst of all of them. Update, 8/98: Meade sent a fourth tube. This one, we had been told, had been personally inspected and used under dark skies by a Meade employee. The OTA arrived. It, too had a rattling lens cell. The owner called Meade and shook the tube into the phone, so the rep could hear it. He told us to test it anyway, which we did. This fourth OTA shows only minor overcorrection, and no astigmatism. Also, it seemed to have somewhat less false color, as well. Optically, it is by far the best of the four units received. Had we wound up with this one to start with, we would have been very happy. On Jupiter, there's a purple halo around the planet at 130X, with a 7 mm Nagler. Detail is good, but somewhat mushy and ill-defined compared with my FS102 (we had set the two scopes up about 4 feet apart for quick comparisons.) No further gains were made by pushing to 189X with the 4.8 Nagler (the Tak still held up well at this power.) M13 and M57 showed good contrast, and the Veil was easily visible -all of it- with the help of a UHC filter and the 30 mm Ultima eyepiece. The Lyra double- double was an easy, clean split, as was Epsilon Bootes. I don't know if it was dumb luck that we wound up with three questionable units in a row, or whether this experience is indicative of a larger-scale problem, but I would urge prospective buyers to use some caution before purchasing one of these. Update 11/98 Meade has just announced a major price cut for this scope. The LXD500 version (reviewed here) has dropped from $995 to $695. You can also get the scope on a less-expensive LXD300 mount for only $595. Now, observers looking for a ~$600 achromat can choose between the Celestron C102HD (reviewed on a later page), and this 102ACHR/500. Note: This scope was discontinued in the late 1990's. Dealers sold them off at very attractive prices, as low as $399. Some owners report issues similar to the ones discussed here, while others had no problems at all and appeared happy with their purchases. Just thought I'd pass that on. 9) Sky Designs 24" Dobsonian (24" f/4 Open Truss Dobsonian, $8300) Though their scopes have never achieved the popularity of the Obsession, Starsplitter, and Starmaster products, Sky Designs has been building premium open-truss type Dobsonians for many years. Run by Bob Combs, Sky Designs lists telescopes up to 20" in aperture. However, he has built at least two 24" models -- the one pictured here, and one for the McDonald Observatory. This is a beauty -and a beast- of a telescope. Although it breaks down into suprisingly managable parts, the assembled scope weighs 270 lbs, with the heaviest component (the mirror) weighing in at 70 lbs alone. The secondary mirror, if turned around, could collect more light than the objectives in most amateur telescopes. Setup can be done by one ambitious person (I've watched the owner do it several times) in about 45 minutes. At the end of every setup, re-collimation of the optics is required. The bearings are quite smooth, although they do stick a bit in cold weather in certain positions (it could be me; a few times I pulled the tube to center an object and almost yanked myself off the ladder. A body at rest tends to remain at rest...) Otherwise, the scope goes where you want it to go, with a gentle tug. It's a tribute to the engineering that you never really feel the telescope's true porkitude. The optics are very well corrected for an f/4 system. I don't notice any aberrations while at the eyepiece. Of course, this could be due to the fact that the owner uses mainly Naglers and Panoptics. It could be due to the fact that the owner usually does an unusually thorough job of collimating the optics. What is more likely, though is that I just don't notice the aberrations because I get a "Holy Cow!" sensation whenever I use this telescope. This is a stunning deep-sky instrument. M51 and M104 look just like their photographs, dust lanes and all. The Orion Nebula will just about ruin your night vision. I've also seen the Horsehead with direct vision. During a club star party, I was fortunate enough to play with the scope for about a half hour, working my way through the Virgo Cluster. What happened to me in that half hour can best be described as "an education." I kept getting lost in simple hops, like the one from M59 to M58. There are so many galaxies, I kept going off-course. In an area around M84/M86, I saw as many as a dozen galaxies in one field of view. Markarian's Chain lives up to its name, and the scope will "split" the Siamese Twins. True story: My first time at the controls of this scope, I decided to go for M31 as my first object. To tell the truth, I wasn't impressed. It looked just like the view through my 6", only brighter. I stepped down the ladder and said as much, to the next person in line. As I walked away in the darkness, I heard, "Ed. Where are you? Come back!" It turns out I had found M32, the small companion galaxy. My sense of scale was completely off with this scope. Now, viewing M31 revealed a massive galaxy, with its dust lane careening through the field of view. That incident had some club members referring to me as "M31" for several months. Highly recommended, to those in the market for a large, premium Dobsonian. 10) TeleVue Oracle 3 (76 mm f/7.4 triplet apochromatic refractor, 2" focuser/diagonal, 26 mm Plossl, OTA only, case, NLA) Classy, compact, and unfortunately no longer available. TeleVue's wonderful Oracle 3. Sold through the early 1990's, TeleVue's Oracle 3 was the predecessor to the Pronto/Ranger and TV85 of today. In fact, it could easily be mistaken for a white-tubed TV85. It comes attractively packaged in a custom fitted aluminum case, although the sample I saw had been sold in the Pronto's soft-sided case. The scope performs marvelously. Its color correction is far superior to the Pronto/Ranger scopes, with just a trace of color on Vega. In addition, the star test was about as perfect as I've ever seen, with perhaps a touch of over-correction on the objective. There's a retractable metal dewshield, and a screw-on dust cap. The focuser is extremely smooth. About the only thing I didn't care for was the fact that the Pronto-style clamp ring isn't drilled or tapped for a finder of any kind. With such a wide field, however (the focal length is only 560 mm) you shouldn't have much trouble finding anything. Nice scope. I wish they still made these. End Telescope Reviews, Page 3

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