For many astronomers who are just getting started, dobsonian reflector telescopes are a popular choice. While many newcomers to Astronomy seek out computerized “go-to” telescopes, some prefer the “no-frills” setup a dobsonian telescope offers.

The Orion XT8 dobsonian is a mid-range reflector telescope. There are a few smaller and less expensive models available in Orion’s classic dobsonian series, and there are a few larger, more expensive models as well. The XT8 offers a good balance between portability, price and performance. In this review we’ll look at the build quality of the XT8, along with how it performs at planetary and “dark sky” objects.

For starters, let’s look at the raw specifications for the XT8. The XT8 features an 8” (203mm) primary mirror. With a focal length of 1200mm, this gives a focal ratio of f/5.9. Advanced observers will enjoy the XT8′s 2” focuser, which allows for larger eyepieces, or even a “T” adapter for short-exposure astrophotography. New observers (or those on a budget) will find the included 2” to 1.25” eyepiece adapter allows the use of 1.25” eyepieces with no noticeable wiggle/slop.

The XT8 does come with a 25mm 1.25” Plossl eyepiece which performs well as a medium-power eyepiece in the XT8. The XT8 features Orion’s EZ Finder II sight. While the EZ Finder II isn’t a terribly bad “red-dot” finder, some observers may see fit to replace the stock finder with something like a “correct image” finder scope, a laser pointer, or even a Telrad non-magnified finder.

Orion ships the XT8 in two boxes. One for the optical tube, and a second for the dobsonian mount base. The shipping box for the mount base was well thought out, minimizing potential damage to the base components. The shipping box for the optical tube was adequate, but as with any piece of delicate equipment – there can never be enough padding.

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With the holiday season in full swing, and many people looking for gift ideas, a telescope is a great choice for anyone interested in Astronomy. For many beginning Astronomers, the hardest part is picking a piece of equipment. The best advice I can give is the “best” telescope is the one you use often.

Too often people end up spending thousands of dollars on overly complicated equipment which is used once or twice, then banished to the closet, never to be used again. Other times, people get cheap, inferior products that provide disappointing views and again, are banished to the closet.

Important considerations regarding telescope are aperture, cost and quality.

Many people will tell you “bigger is better” with regards to aperture, and this is true, to a certain degree.
While it is true that a 12″ telescope will have far more light gathering than say, a 3″ telescope – such a large telescope may be unwieldy and difficult to transport. Consequently, a small 3″ telescope may not bring in enough detail on objects.

In this economy, cost is definitely a factor. Buyers want the best value for their money and want to make sure they are receiving a quality product. It is inevitable that lower cost telescopes will have fewer features or less robust construction than a higher cost unit, but there’s a HUGE difference between “inexpensive” and “cheap. The previous distinction is what I believe to be the most important factor in quality.

There are many different technologies that have been used on telescopes since the 1600′s. Today many manufacturers can use plastic lenses instead of glass, fiberboard tubes instead of metal, black paint instead of flocking, etc. Construction is important in a telescope, and generally speaking, the more expensive, higher end telescopes are built to last for years, due to better materials and better mirror/lens coatings.

There are two lower end telescopes I that I use quite often.  

The Galileoscope was created as an International Year of Astronomy 2009 project and is a great tool to use for outreach events. This telescope mimics one of Galileo’s original refractor (lens based) telescopes. At a cost of about $50 this telescope is priced well for what you receive.

The telescope is of inexpensive design, and is sold in “kit” form, which I feel makes this telescope an excellent teaching tool.  One other feature is the 1/4-20 mounting nut on the bottom of the telescope that allows the Galileoscope to be used with virtually any tripod.

The other inexpensive telescope I use regularly is the Celestron FirstScope 76mm Dobsonian Reflector.  This telescope, while being small brings out quite impressive views of Solar System objects and some nebula like M42 (Orion Nebula).  The “table-top” design makes this a nice “grab and go” telescope to take when camping.  (I’ve since mounted mine to a tripod)

I suggest purchasing the Celestron Firstscope with the optional accessory kit, which includes a moon filter and two additional eyepieces.  While the included eyepieces are inexpensive, the moon filter will be invaluable since that is one object the Celestron Firstscope excels at viewing.

You can find the Celestron Firstscope model in stores or online from around $30, to the $50 range for a “bundle” with the acessory kit.

Both of the above telescopes are inexpensive “starter” telescopes that will easily last long enough to keep a new Astronomer interested until they can “graduate” to a more robust telescope.