best telescope to buy?

Question

I am looking for a telescope and I saw two I like but I dont know which one to choose....

1) Orion Skyquest 8" dob
or
2) Celestron starhopper 8" dob...

Which one has better optics....

also what is a 2x barlow, i heard about it on answer but dont know what it is... thanks

I want to use it for viewing deep sky objects.... this will be my first telescope...

Are there any other good dobs with good price out there?

Answer 1

In all honesty, both telescopes would likely have about equal optical quality, which means they would have good or very good optics. The mirrors could be better perhaps, but the optics of both are made aboard and many are surpisingly good for mass produced optics. Premium optics fetch a premium price, but there are lots of telescopes out there with good or very good mirrors that would please all but the most demanding observers. You would find that most if not all of them deliver nearly identical images of star on both sides of best focus, a sign the optics are of good quality. Indeed, it should be remembered that to really be able to distinguish a good from an excellent mirror, you need a very steady night and magnifications well above 300X. Most nights won't allow this before the image blurs due to turbulence in the atmosphere. I think you will be happy with either one, and rememeber you can upgrade them at any time with things such as a better focuser, a Telrad finder, better eyepieces, nebula filters, even digital setting circles.

An 8-inch F/6 Dob is an excellent choice for all around observing of Solar System and Deep Sky objects. A barlow lens is for doubling, tripling or otherwise increasing the magnification your telescope gives with any eyepiece. A 25mm eyepiece that gives 48X would give 96X with a 2X barlow. They are very useful for high magnification observong of the Moon, planets and double stars because you can get high powers without the usually tiny eye lenses and short eye-relief high power eyepieces have. They make high power viewing more comfortable, and most of the time you would be using your low and medium power eyepieces anyway. A barlow in effect double the number of eyepieces you own. Make sure you buy a good one, which will have multicoated optics, and well blackened inside to surpress ghosting from stray light. Avoid the variable power barlows, they tend to be not as good optically as the fixed power models. A standard 2X will serve you well.

You'll want to buy a sight tube so you can properly collimate the optics. Like a piano, Newtonians and Dobs require occassional alignment of the mirors, which is easy to do and critical for good performance. You will also need a chair or a stool, a star atlas and a red filtered flashlight. I reccommend the Sky & Telescope Pocket Star Atlas. It's very readable and had many great objects for this size telescope plotted in it. As telescopes go, a 6 or 8-inch Dob is one of the best choices for a beginner. Below are a couple of links for you, the second one is to my site where I have sketches of all manner of deep sky objects. Some of them were made under pretty bad conditions, but others were made under near perfect sky conditions.

Answer 2

First, they are the same telescope, the only difference is the Price and the Paint Job.
These scopes make excellent beginners scopes with very good optics and good quality materials.
They are made by the Synta Company in China, in the same factory.
My personal favourite is the Orion, because the Orion company is famous for it's customer service, which can be a great help to a beginner.
If you look at the Orion catalog, you will see that hese scopes come in two versions:
1. The XT8 Classic 2.) The XT8i intelliscope with electronic setting circles which catalog lots of objects for you.
For a beginner, I suggest the classic version. The electronics on the intelliscope are "nice to have", but don't make the scope see any better. Spend the money on an extra eyepiece or two ( especially one low power eyepiece, the 32mm Ploessl for example).
The Telescope comes with two eyepieces already and also comes with planetarium software. This software is the most useful accessory of all. After you load and initialize it, it will display an exact view of the sky from your house. This makes it a great tool for learning where and how to find objects in the sky. It lists literally millions of them. Learn how to use it.
The Barlow Lens increases the focal length of your telescope from 1000mm to 2000mm.
Why should you care?
It has the EFFECT of multiplying the magnifying power of each eyepiece you own by a factor of 2X
To figure out how much your telescope magnifies, divide the focal length of the telescope by the focal length of the eyepiece.
For example, with a 10mm eyepiece the telescope alone with it's 1000mm focal length will magnify 100X, ( 1000mm/10mm = 100X )
If you insert the barlow lens in addition to the same 10mm eyepiece, the magnification is 200X ( 2000mm/10mm = 200X )
Now you can see why the advertising hype of 675X for example, is meaningless B.S. , because you can change the magnification at will, just by changing the eyepiece.
Claims like 675X are ridiculous anyway, all you would see ( if anything) would be a blur.
Even in my 16" Dia Telescope, the Atmosphere alone will not allow that much magnification and still have a usable image.

Adolph

Answer 3

They are equally good telescopes so I'd choose the one which gives you the better deal.

A 2x barlow is a special lens attachment that basically doubles the magnification of any eyepiece. Technically it increases the focal length of the telescope though.

Magnification = (focal length of the telescope)/(focal length of the eyepiece)

A 25mm eyepiece is lower powered than a 12.5mm eyepiece, but if you use a 25mm and a 2x barlow you will get the same magnification you would if you used a 12.5mm eyepiece. You might wonder why someone would use a barlow instead of a higher magnification eyepiece. The answer is, generally the lower magnification eyepieces have a larger hole to look through and you don't need to be as close to the eyepiece, so it's more comfortable to view through them. When you attach a barlow to increase the magnification, you retain the physical properties of the lower magnification eyepiece so you get more magnification with a more comfortable view.

It's important to note that most viewing you will be doing should be done using a lower powered eyepiece. High power is difficult to use and really only needs to be used to see detail on planets and resolve certain binary star systems.

Answer 4

Either of these is an excellent choice for a first telescope. The optics will be about the same in both, maybe slightly better in the Celestron.

A Barlow lens is a negative lens you place between the eyepiece and the telescope, which has the effect of doubling the telescope's focal length or halving the eyepiece's focal length; the end result is doubling the magnification. This is a relatively inexpensive way of doubling the magnifications available with a given set of eyepieces, and also of getting high magnifications without resorting to the tiny lenses of smany short-focal-length eyepieces.

Answer 5

Hi. Larger optics usually will show more detail but ALL Dobs need you to know where to point in the sky. Learn the sky first by using either a planisphere or a program such as http://www.stellarium.com/ . You will have more fun if you know where to look!

Answer 6

I believe they both have the same optics. get the one with the best options

Answer 7

Don't buy a dobson, I suggest CELESTRON 114 NEXSTAR SLT!