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Celestron Astromaster 130 EQ
by Revier
I cut my astronomical teeth on Celestron's refractors and as such the company is synonymous with nostalgic fondness in my mind, however, that was a long time ago and the world of astronomy has moved on since then. Have Celestron managed to keep up with the curve with their low cost reflector, the Astromaster? Well, the answer is ... yes...and no.
The Astromaster's strength undoubtedly lies in it's affordability and all of its attributes should be judged primarily against this criteria. Are there better optical performers out there? Yes! Are there sturdier and more solid mounts out there, without question! But few scopes manage to provide these things at such an alluringly low price.
The optics are solid and perform competently whether you're viewing the lunar surface or taking in those wispy and ethereal 'faint fuzzies' comprised of distant galaxies and nebulae. At F5, the larger more diffuse galaxies stand out well and are beautifully framed in lower powers, as are the myriad open clusters that dot the northern hemisphere but with a focal length of 650mm the use of higher powers will be needed to discern fine detail on planetary discs.
The scope is relatively light at around 24lbs and setup is quick and straightforward , it's always a relief lifting a tube this light when compared to my main 12" Dob which weighs almost as much as I do!
The CG-3 mount is adequate but does suffer from vibration issues and is too wobbly to be considered excellent. It does serve its purpose though and when you're only parting with £150 it's hard to be overly critical.
It even comes with an erecting eyepiece (though very cheap and plasticy) which means you can indulge in a little twitching (if you're that way inclined). The job of the erecting EP is to orient images the 'right' way up so when looking through the eyepiece, the object appears as it would through the naked eye rather than upside down or turned about.
All in all a plucky scope that is ideal for the frugal Astronomer and beginner alike. It provides those on a budget with a basic (but functional) tool with which to view the heavens and as such must come highly recommended.
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Meade ETX-90
by Revier
Since advances in lens/mirror design have made the telescope available to the general populous, Astronomers have continually lusted after bigger and bigger scopes in a phenomenon known as aperture fever, in Astronomy, bigger is usually better. But that doesn't mean we should overlook the smaller offerings out there that sacrifice light ... gathering power for portability and ease of use.
The ETX-90 from Meade is one such example, a short barrelled Maksutov-Cassegrain with an aperture of 3.5". With a focal length of 1250mm and a tube length about as long as your forearm it's very easy to transport to darker skies. A rather slow focal ratio of F13.8 means it will get most of its use on Solar system objects.
Setup is a doddle to, no heavy tubes to stagger about with, you'll be ready to go in no more than 5 minutes. It must be said that the mount leaves a little to be desired, it's not the sturdiest, luckily it doesn't have to deal with alot of weight (the OTA weighs 9.2lbs).
Perhaps the most notable feature of the ETX is the Autostar, the GOTO system with a database of some 30,000 objects. Using the handheld remote, plugged into the mount, you can automatically slew the telescope to track any one of those objects (although the small aperture plus the slow F ratio means most of the 30,000 will remain elusive except in the darkest, most pristine skies) . It only takes a few minutes to get it running, just align the mount to the North, level the tube and align the scope on two stars near the horizon and you're off.
Now personally, I prefer learning my own way round the night sky, it's more satisfying and means you can afford to get a better scope as you're not paying for the gadgetry. Having said which, the technology is useful for the beginner and if you aren't the most patient person in the world it certainly cuts time between observing objects. There is also something quite cool about it (almost like your controlling a cannon).
The ETX isn't the most amazing scope out there, once you strip away the technology what you're left with is a small scope on a lacklustre mount, but it is very portable and the optics are fair, as such I would recommend it to the beginner or those who travel alot.
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HM5 Polar Alignment Scope for EQ3-2
by Revier
If you own an equatorial mount then chances are you will be familiar with the necessity of at least a rough polar alignment. Equatorial mounts allow telescopes mounted upon them to follow the motion of the stars across the sky, keeping objects inside the field of view with only a turn of a right ascension or declination nob. This is ... preferable for visual observation but becomes vital for effective imaging (especially when deep sky objects are concerned).
This light weight polar scope fits snugly into an EQ3-2 (CG-4) mount. Before it can be used effectively though, the polar scope itself must be aligned to the mount. This is a simple process that can be done day or night and only takes about 5 minutes to do.
The polar scope is similar to a low powered eyepiece when looked through, with one very important difference, etched onto the glass is a central X marking true north, a small circle in which to position Polaris as well as two other circles for two other bright stars and a diagram representing the orientation of Cassiopeia and the big dipper. When those three stars fit neatly into the etched circles you have polar alignment. It is important to remember though that the diagrams of the constellations are only there as a sign post as to the orientation of the constellations, you will not be able to align the scope so that the etchings fit over the constellations.
The Skywatcher polar scope is indeed easy to use, amongst other examples it holds it's own and is definitely a great choice for £30. Aligning the polar scope takes only minutes and is achieved easily using the three metal thumbscrews on the mount. Setting the polar scope to the correct position within the mount is easy, simply match the numbers on the mount to the numbers printed on the large silver ring around the scope and that's all there is to it.
If you've decided that a polar scope is necessary for you then there really is no need to look further than Skywatchers offering. In essence it does everything that 90% of other polar scopes do for the lowest cost.
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