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Orbitor 4.5 |
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REVIEW ARCHIVES Refractors Barlow
Lenses LINKS FAVORITE LINKS NASA
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The Review Hello everyone!
This will be a review of the Orbitor 4.5 inch f/8 Newtonian
reflector on a Dobsonian mount. This
telescope is available on the Khan Scope Centre web-site:
http://www.khanscope.com
The telescope comes fully assembled.
There are two of the newer generic Plossls included that seem to be
popping up everywhere. They are 25mm and 10mm with 50 degree fields.
The 25mm is a pretty nice eyepiece with decent eye relief.
The 10m has sharp images, but it’s lacking a bit in the relief
department and eyeglass wearers will have to remove them, if you want to
see the whole field. The cost
of this ‘scope is $159.00 The rocker box is nicely finished, and
has very nice and smooth azimuth motion.
The tube is steel with a fully adjustable mirror cell.
The spider is one of those three vane ones that were being used on
the Orion XT series until this model year.
It is also fully adjustable. The
focuser is an all metal rack and pinion unit that works fine. (1.25 inch
only). Not the smoothest
I’ve ever seen, but at this level, it’s pretty good.
If you have not seen one of these Taiwanese 4.5 inch Dobs in person
before, you would be shocked at how small it seems compared even to a 6
inch. This telescope is marketed as a child's beginner ‘scope and as such, it works fine. BUT, not with out a little help and guidance from an adult. Optically, the ‘scope is an o.k. performer. There is some spherical aberration, not much, but it’s there. Views of the Moon, star clusters, and other deep sky images are not much affected by this. However, Jupiter’s cloud bands are not all that clear, (though they can be seen). The same is true of Saturn’s rings.
They are there, but don’t expect to drive a truck through the
Cassini division. Still, all
in all, the images are decent and much better than beginner ‘scopes in
my day. There were two problems (at least in my kids example) that had to be addressed before I could turn the kids loose with it. One was the focuser had excessive slop. This was easily adjusted, and was straight forward. I think it might have been a quality control problem at the factory, because once fixed it has stayed that way after a whole year of use from my kids. The other thing that had to be addressed was a balance problem. I looked at how others had dealt with this problem, and decided against any mechanical tensioning devices. What I did instead was take the ‘scope down to the local hardware store. I tried all the various eyepiece combinations while adding and subtracting magnets. Once I had acceptable balance worked out, I showed my kids what magnets worked
with which eyepieces, and they were off without looking back. This telescope has taught my children
how to find objects on their own, using a finder scope.
It has also turned my 12 year old into my weekend observing
partner. She is ready to move
on in aperture. The 8 year
old now is looking forward to being the one “in charge” of what she
observes. These things alone, make me pleased with this ‘scope, as
you cannot put a price on them! So.... Is this telescope recommended? Well, yes, with reservations. If you care to deal with the balance issue, it makes a great child’s beginner ‘scope. I would not however recommend that an interested adult start out with this telescope. You would be much better served with one of Guan Sheng’s 6 inch f/8 parabolic Dobs.(available on the Khan Scope Centre site as Sky Mentor, and on the Orion site as the Sky Quest XT6 http://www.telescope.com) The greater light gathering capability, and clarity of the parabolized mirror is worth the extra money. Submitted by Ed Conley - econley@lcisd.k12.mi.us - Michigan, USA
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