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Spend more, get more: money can't buy you love--but it can get you a great telescope.

You can buy a very good telescope for less than $1,000--one that will serve you well for the rest of your life. So why would anybody want to spend more? Plenty of reasons!

Do you want to take pictures of galaxies and nebulae, and are you sure that you have enough time and dedication for that difficult pursuit? You can do long-exposure astrophotography with a modestly priced telescope, but it will be a lot easier if the scope's on a rock-solid mount that can track the sky with pinpoint accuracy--which will cost more than a standard mount.

Are you a visual observer eager to explore the structure of galaxies through the eyepiece? Dark skies are a prerequisite, but you'll also need all the aperture you can get. On the other hand, you need to pay careful attention to portability unless you have a permanent observatory. Squeezing the maximum performance into any given size and weight inevitably raises a telescope's price.

Finally, everybody likes fine quality; flawless images and silky-smooth mechanics are wonderful in their own right, quite aside from their practical benefits. Sure, you can get surprisingly good scopes for very reasonable prices, but if you're going to devote yourself to the hobby, why not get the best, even if it does cost more?

Reflectors

If you want a really large aperture for the lowest possible price, a solid-tube Dobsonian reflector is your only choice. The downside of such a scope is that it's likely to require a pickup truck for transportation and two or more people for setup.

The truss-tube design goes a long way toward solving those problems; it uses a lattice of rods in place of the solid tube, allowing the telescope to be disassembled for storage and transportation. Truss-tube Dobs cost more per unit of aperture than ones with solid tubes, but most people consider that price to be well worth paying.

Large Newtonian reflectors on equatorial mounts aren't as popular as they used to be, but they still have plenty of aficionados. The combination of motor drive, large aperture, high optical quality, and relatively modest price is appealing to many planetary observers and astrophotographers.

Refractors

High-quality refractors offer the best optical performance that can be achieved with any given aperture, as long as false color can be kept to negligible levels. Until recently, that required a long focal ratio, but modern apochromats can achieve superb color correction in short, convenient tubes. These refractors are not cheap, and for the same money you could buy a reflector or catadioptric that would always show fainter objects and would often show finer planetary detail as well. But nothing can match the aesthetic appeal of optical perfection. Refractors also have great practical value in situations where large-aperture instruments cannot be used effectively because of portability constraints, insufficient cooldown time, or unsteady atmospheric conditions.

Apochromatic refractors with short focal ratios offer unparalleled wide-field performance, a characteristic valued highly by many deep-sky observers and astrophotographers. They are also very popular among travelers because they're extremely rugged and pack a lot of performance into a small package.

Catadioptrics

No single telescope can do everything for all users, but 8-inch Schmidt-Cassegrains come pretty close. They've got enough aperture for serious deep-sky observing, yet they're small enough to carry easily in a car. Best of all, their short, lightweight tubes allow them to be packaged with custom-designed motor-driven mounts that are solid, are accurate enough for astrophotography, and have computerized Go To capability. For a little more money (and weight), you can also get Schmidt- Cassegrains in larger sizes.

Maksutov-Cassegrains are very similar to Schmidt-Cassegrains, but they tend to be optimized for high-power viewing. Maksutov-Newtonians offer even better optical performance per unit of aperture, but they're not as compact. Most Schmidt-Newtonians are optimized for a well-corrected wide field.

Mounts

Premium telescopes are often sold without mounts; "optical tube only," as the advertisements say (though note that the price we list always includes the cost of a mount). This is convenient for experienced astronomers, who often own several mounts and several optical tubes and mix and match according to their needs. For instance, one might put an apochromatic refractor onto a heavyweight equatorial mount for astrophotography but use the same scope on a lightweight altazimuth mount for airplane travel.

Other Options

We have covered only the most common categories of telescopes; there are dozens of others, including, but not limited to, classic Cassegrains, Ritchey-Chretiens, off-axis Newtonians, and old-fashioned long-focus achromatic refractors. Each suits a particular need and has its own adherents. And while we tried to include scopes from as many manufacturers as possible in our guide on the following pages, space limitations made it impossible to list them all, especially the one-person companies whose proprietors typically construct telescopes as much for love as for money.

Another thing worth considering is that a few thousand dollars buys quite a lot of an experienced telescope maker's time. If you can't find exactly the telescope that you want, you might be able to get somebody to custom-build it to your specifications. And of course, building it yourself may be an option.

But whatever you choose, research carefully before you buy. Even in this price range, there are variations in quality and capability. For instance, not all the mounts are suitable for long-exposure astrophotography--nor do they need to be if you plan to use them only visually. Read all the reviews you can lay your hands on, especially those in reputable sources like Sky & Telescope. Ask at your local astronomy club if people in your area own similar scopes; they will probably be delighted to show them off to you. If you're going to spend a few thousand dollars on a telescope, you owe it to yourself to do the job right.

* SOLAR TELESCOPES

People rarely think about doing astronomy during the day, but the Sun is viewable for more hours every year than any other celestial object. When the Sun is in an active phase, you can see sunspots just about any time you want with the aid of an inexpensive white-light solar filter. But if you are willing to spend some serious money, you can buy a hydrogen-alpha filter, which lets through only the light emitted by the Sun's upper atmosphere. The hydrogen-alpha Sun has to be seen to be believed; instead of the usual blank disk with occasional sunspots, you see activity everywhere, like a giant pot of boiling water, changing from one minute to the next. Best of all are the great solar prominences, many times larger than Earth, that can otherwise be seen only during total solar eclipses.

Hydrogen-alpha filters can be purchased as separate accessories from several manufacturers, but two companies (Coronado and Kendrick) have created dedicated telescopes incorporating hydrogen-alpha filters and designed for optimum performance at that wavelength.
Manufacturer           Coronado         Coronado      Coronado
Model                  P.S.T.           MaxScope 40   MaxScope 70
Price (US$)            $499             $1,699        $2,999
Aperture               40 mm            40 mm         70 mm
Focal length f/ratio   400 mm f/10      400 mm f/10   400 mm f/5.7
Comments               Tabletop mount   Comes with    Comes with
                         optional.        mounting      mounting rings,
                                          rings.        25-mm eyepiece.

Manufacturer           Coronado            Kendrick
Model                  MaxScope 60         SolarView-50
Price (US$)            $3,685              $4,393
Aperture               60 mm               40 mm
Focal length f/ratio   400 mm f/6.6        400 mm f/8
Comments               Comes with          Star diagonal
                         mounting rings,     and eyepieces
                         25-mm eyepiece.     not included.
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Title Annotation:Telescope Buyer's Guide
Publication:SkyWatch
Date:Jan 1, 2005
Words:1239
Previous Article:120 scopes priced from $199 to $999.
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