Tag Archives: Reflectors

Is an 8″ Dobsonian the Best Telescope for a Beginner?

A boy and his Dob viewing the Moon.

Follow any discussion of a beginner asking about a first telescope and it won’t be long before an 8″ Dobsonian is suggested. It might be the most recommended scope for beginners, and not without good reason, though there are several factors that should be seriously considered before buying one.

A Dobsonian is a Newtonian reflector on a simple alt-az mount. Before John Dobson popularized his simple, inexpensive mounting method, German equatorial mounts were commonly used, which were by necessity large and heavy, and thus expensive. By comparison an 8″ or greater Dobsonian becomes relatively affordable and portable.

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A Night to Remember

I haven’t looked through a telescope in weeks. The second half of April seemed an endless string of cloudy nights and while I’m sure there were a few clear ones in there, one thing or another kept me from getting out under the stars with a telescope.

I am starting to miss observing and I can’t help but recall one of the last sessions of April, which happened to give the best views of Jupiter I’ve yet seen.

I was enjoying a pleasant evening out in the back yard with the kids when I first noticed Venus visible in the southwest and shortly after that was able to spot Jupiter, with some difficulty as the sky was still blue, near the zenith so I decided to bring out the 10″ Dob. Only a few weeks earlier I would’ve chosen a smaller scope but due to the mild weather that day I suspected the telescope would not need much, if any, cooling before being usable at high powers.

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The Leo Triplet

Annotated finder chart for the Leo Triplet. Original chart from the TUBA Atlas.

Annotated finder chart for the Leo Triplet. Original chart from TUBA.

During the month of April the constellation Leo is high in the sky shortly after dark, making it a good time to view the many galaxies residing there. As seasoned observers know, viewing galaxies at higher altitudes puts less air between you and the subject giving a clearer view. I’ve spent the past few weeks eagerly awaiting a clear, moonless night so I could revisit M65, M66, and NGC 3628 – collectively known as the Leo Triplet.

After a long stretch of cloudy or moonlit nights, last night’s skies were clear and reasonably dark from my red zone backyard so I brought out my 10″ Dobsonian along with a 5″ refractor to view this trio of Galaxies.

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Using the AWB OneSky as a Travelscope

Photo: OneSky travelscope

My OneSky travelscope in action. This photo was taken before adding the shroud described below.

The surest way to improve any telescope’s performance is to get it out under a darker sky. Living in suburban Massachusetts I’d have to drive significant distances to get to skies much darker than the one available from my red zone backyard. The darkest skies I regularly encounter are on family trips to rural areas.

Of course trying to fit a telescope into a car already packed with the whole family and all the associated cargo can be a challenge. Thus begins the search for a more portable telescope or travelscope. To my thinking a travelscope can be any telescope setup that prioritizes volume and/or weight over other concerns such as aperture or mount stability. Every one has their own circumstances and priorities and so travelscopes can look quite different from observer to observer.

As I mentioned in the general review of the AWB OneSky Telescope, my intent when buying the OneSky was to use it primarily as a travelscope. The OneSky appealed to me for its packed aperture to volume ratio and ease of setup.

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Celestron FirstScope Review

Photo: Celestron FirstScope

The FirstScope and included 20mm and 10mm eyepeices.

Small, inexpensive telescopes have an appeal all their own. Ideally they are simple to use and though they don’t collect the most light or have the highest quality optics or most robust construction, under a clear night sky they can reveal a host of wonders. In practice few of these cheap telescopes actually live up to these aspirations and many of them are so flawed in optics or mechanics as to be more frustrating than fun.

The Celestron FirstScope (you can also find it at Amazon) is a small, 76mm, reflector that has interested me for some time. It is incredibly inexpensive; the regular price is under $50 and I’ve seen it on sale for under $35 from time to time. So what makes the FirstScope any different from countless other cheap telescopes?

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AWB OneSky Telescope Review

Stock photo of the OneSky courtesy of Astronomers Without Borders.

Stock photo of the OneSky courtesy of Astronomers Without Borders.

A well designed, compact 5″ telescope and mount for $200? It may sound too good to be true but despite a few caveats this 130mm f/5 reflector is a capable telescope at an outstanding price.

Astronomers Without Borders (AWB) is an organization that offers astronomy outreach programs all over the world. The OneSky telescope is made for Celestron in China and sold in the US by AWB to help fund these programs. My intent in purchasing the OneSky was for use as a travelscope but for now I want to focus on its suitability as a general use telescope.

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