NOTE: This review was published on my original site back in June 2002 – leaving it here with the original date, pics and text – plus for my now adult children to see some old photos of themselves!
So, how much telescope does $1000 buy you these days? How does a metal tubed 10″ Dob sound?
Too good to be true, or a real celestial bargain? In this review we make some surprising findings. Read on…..So, you want to buy a telescope……Well, you’ve got a fair number of choices!
Dobsonian, SCT, computer controlled, APO etc – all a bit confusing for the budding star gazer who want to make the move from their “first” telescope into something a bit more serious. What’s more, the amount of $$$ you’re going to have to fork out varies depending on features. For example, the prices of 8″ reflecting telescopes advertisted in the Jun-July 2003 Sky Space range from less than A$500 to over six grand!
Of course at the higher end of the scale you’re going to get a computer controlled, all singing, all dancing scope that has every feature under the Sun (or stars….) But what if you don’t want a computer controlled telescope ? What if you either just want the largest telescope you can get for your dough, or your budget doesn’t stretch that far?
The way to go might be to look at either getting or making one of the simpler forms of reflecting telescope – a Dobsonian. I won’t go into what a “Dob” is here. There’s plenty of stuff on the net about them, or simply ask at your local Astronomical Society.
There’s no doubt that a “Dob” will give you the largest aperture for your dollar. The downside is they’re often bulky and not as portable as a folded optical system such as a SCT. They also are aimed mainly at the visual observer. Yes, you can take photos through them – but with difficulty.
There’s been a number of retailers in Australia who’ve started selling imported Dobsonian telescopes, mainly sourced from China or Taiwan. This in itself is not a bad thing. The Taiwanese especially, have been making optical components and accessories for some time. But what about a whole telescope? The telescope on review is here a 10″ Dobsonian, the GS-880, from the Guan Sheng Optical Company in Taiwan. It was obtained from the their Sydney dealer, Andrews Communication. This style of telescope is also available in 8″ and 6″ sizes.
I should point out here,this telescope falls into the category of being an “Orion XT Clone”. It’s very similiar, although not 100% identical, to the SkyQuest XT10 from Orion.
It’s also sold in other parts of the world such as Canada and South Africa under a range of other names including SkyMentor. I won’t get into the debate as to whether it’s worth paying the extra price for Orion name or if you should (according to Orion) Beware of Inferior Look-alike Telescopes. I’m not going to touch this one with the proverbial ten foot barge pole. You might like to discuss among yourselves.
What do you get ?
The telescope comes in two boxes. One measuring 140 cm x 48 cm x 46 cm at 24 kg that holds the main tube and accessories and another at 64 cm x 64 cm x 14 cm that holds the base. The base is flat packed, sorta like an Ikea coffee table (more on that later…) One thing’s for certain – this is not going to fit in a regular sedan or hatchback! Considering the port of origin and length of journey, the boxes show no signs of damage or hard knocks.
The telescope itself is a 25cm (10″) F5 Newtonian. The tube is metal, beautifully finished in black enamel. It has thick metal endrings with hammered metal finish. A very smooth 2″ focusser sits up top. The overall impression is of a solid, well made bit of gear.
The finder is 8 x 50mm, with a neat dovetail locking system. The finder adjustment is via two nylon screws acting against a spring loaded pin. Three Plossl eyepieces are included – 25mm, 9mm and 6mm. These give 51x, 141x and 212x respectively.
Not an ideal choice of sizes, but considering the cost of the whole setup, the fact you get more than one eyepiece seems a bit of a bonus. There’s a neat eyepiece holder that screws into the side of the base with room for three 1 1/4″ and one 2″ eyepiece. Oh, you also get a screw-in Moon filter.
The base is laminated chipboard. It looks pretty solid, but anything made of chipbard and held together with a few screws is not going to last forever. A quick ring around a few local cabinet makers indicates a replacement of high quality plywood and made to “pass onto your grandkids” is going to set you back around two to three hundred dollars.
The chipboard base is not going to wear out in a hurry, but when it does, you know it won’t cost you a fortune to replace. For $999 inc GST you get a 10″ F5 steel tubed telescope, mount, 8 x 50 finder and three eyepieces.
Now we come to about the only major drawback to the whole telescope.
It came with virtually zero documentation – just one page showing an exploded view of the base.
Despite this, the base went together with no problems. In fact, most of the assembly was done by my 12 year old son. The only two slight hiccups were, there were no pre-drilled holes for the rubber feet, or for the eyepiece rack. All the screws, nuts, allen keys and other bits of hardware were included. You’ll need a screw driver and, maybe a small shifting spanner.
Still, if you spend $1000 on anything you have the right to expect better documentation than this.
There are no details on how to install the finder or the side springs that help the scope’s balance. There is no mention of how to focus the finder. Not even a rough beginner’s guide on how to use the telescope.
It’s basically figure it all out yourself, ring Andrews Communications, or if you’re a bit naughty, you can download the SkyQuest XT10 manual from the Orion website…… The other problem the lack of documentation is going to cause a beginner, is collimation. The telescope arrived in need of a fair bit of secondary mirror tweaking. The main mirror was pretty much spot on.
Size – it’s big!
This telescope is at the upper end of what one person can comfortably handle. The combination of size and weight make this a bit of a handful. If you’re not happy with the idea of carrying something like this around, I’d suggest maybe look at going down to the 8″ or 6″ models. You will see less, but then again you might get to use it a bit more.
How does it handle ?
In general, the motion of the telescope is very smooth. The mount is extremely steady and easily positioned. Even with the fancy tension spring system fitted, there’s a slight tendency for the telescope to be marginally bottom heavy when pointing towards the zenith. The suggestion from SkyMentor owners seem to be to either remove the bottom metal plate over the rear of the mirror cell (which also helps in cooling), or simply place a weight, using a magnet, at the top of the tube to help balance the thing. I must point out that the balance issue is very minor.
The straight through finder is a real neck breaker! You’re going to save a lot of money on chiropractor’s bills if you get a right angle finder. I did find the two screw/one spring loaded pin finder alignment very easy to use. This system probably doesn’t hold the finder as steady as the two ring/six alignment screws arrangement, but it is far easier to align the scope and finder.
Through the eyepiece.
After you’ve figured out how to put it all together, lug the thing outdoor and collimate the optics, what’s the view like?
Superb! I have to admit, I was a bit sceptical about just how good the optics on a Taiwanese 10″ telescope for under a grand could be. After spending some time at the eyepiece of the GS-880, I’m impressed. Star images on both sides of the focus show that this telescope has well figured optical surfaces. I haven’t yet pulled the mirror out and put it under the Ronchi tester, but when I do I suggest it will look ok.
Not surprisingly, the ‘scope performed well on the “usual suspects”. It gave very detailed views of Jupiter, as well as some really thrilling lunar views, even under high power. It split a number of close binaries.
However, when it came to some of the deep sky objects, the GS-880 came into its own, showing what a good set of optics and ten inches of aperture can do. It gave spectacular views of some of the brighter stuff such as Eta Carina, M6 and a whole swag of open clusters. Omega Centauri, even at low power, fills more than half the field of view. When viewing galaxies such as NCG5128, M83 and M104, I can understand how people get “aperture fever”!
At F5, it’s almost a wide field instrument, but with that much might gathering power, as you swing around the sky you’ll keep running across small grey “fuzzies” you haven’t seen before, that will have you reaching for the charts!
The supplied eyepieces were Ok. Not bad, not fantastic. I certainly noticed a big difference when I put in a Televue Plossl of the same length. Once the tube was balanced, the mount proved to be rock solid and makes viewing under high power a breeze. It’s always hard to compare what you can see through various scopes. I’d take a stab at it and say that it compares very well with say a Celestron 8″ SCT for bright objects such as the moon or planets. If you’re into looking at galaxies, nebulae, clusters etc then the extra light gathering power of the 10″ mirror will really come in handy.
Have you ever read a camera/software/hardware/whatever review where the person writing it decides at the last moment, that they can’t make up their mind and suggests the reader “decide for themselves” ?
Well don’t worry – I’m not going to do that to you!
There’s no doubt the Guan Sheng GS-880 is a very good telescope. It’s well made and has great optics. It is let down very, very badly by the almost complete lack of documentation.
As it’s basically a “no-name” telescope, just waiting for someone else to put their own “brand” on it, it’s not surprising. On the flip side there is an active Internet community for this type of telescope, so between that and the dealer, you’re unlikely to get stuck.
Given this, and the size of it, I would suggest that the GS-880 is not an ideal telescope for a beginner. However, if you’re a more seasoned observer and are looking for something with a bit more oomph I think you’ll want to look very closely at the GS-880. I’d suggest some higher quality eyepieces, and investing a little time in getting the minor issues with the balance and mount sorted out. At the end of the day, the thing that stands out, is just how much telescope you get for your dollar. I wouldn’t be concerned or worried about this being a cheap clone or knock off. It’s certainly built to last and will give you many years of happy viewing.
Factor in the $999 price tag and you’ve got a winner!