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smenkhare
25-06-2006, 05:59 PM
Hi.
i'm new here and just getting into astronomy (although i've been interested in space since primary school.) and looking to get my first telescope. The one i'm interested in is the skywatcher 76
http://www.andrewscom.com.au/site-section-10.htm
is this any good?
also, i've seen a lot of articles on making your own optical telescope, does anyone here know anything about making my own radio telescope?

thanks.
Peter

mickoking
25-06-2006, 07:00 PM
G,day Smenkhare and welcome to IIS :welcome:

I had a look at the link to andrews and I have a few suggestions for you. It is my humble opinion that the skywatcher 76 is too small for serious observing. Your best bet (on the Andrews site) is the Guan Sheng 150mm (6") Dob for $299 or the GS 200mm (8") Dob for $399. GS Dobs are very capable telescopes, I own 2 my self :thumbsup:

Cheers, Mick.

smenkhare
25-06-2006, 07:35 PM
hi mickoking
thanks for the reply, i had a look at those but don't really like the design of the dobsonian telescopes. Is there anything similar that's tripod mounted?

janoskiss
25-06-2006, 08:33 PM
Welcome Smenkhare!

Once you use a Skywatcher 76 on the wobbly AZ1 mount you will appreciate the studiness and stability of a Dobsonian mount, not to mention the views with a much larger aperture scope. I recommend you go along to an observing session at a local club, or maybe with some Sydney people on this forum, and get to experience some scopes for yourself before buying anything.

[1ponders]
25-06-2006, 08:35 PM
There are plenty of people here who get together for viewing smenkhare, and my suggestion is before you spend your hard earned on that 76, which really will be more of a pain than you can possibly believe, get out and have a look through a few scope. That scope just might be Ok for looking at the moon and maybe Jupiter and Saturn, but the mount will drive you to distraction. A common name for that sort of mount (and the similar eq mount) is a "wobbletronic". They are not worth the money. All they do is discourage the majority of people away from astronomy. I'm not saying that there aren't people who enjoy using them, but the most find their way into back closets and never get used after the first couple of times. We have the same mount with a refractor on it at the observatory where I run classes and we using to demonstrate to people what not to buy. Invariably if inexperienced people are asked what sort of telescope they are thinkin of getting they grab it first (or the similar eq). Wy? because that is the sort of telescope they have seen on TV or in magazines (D.ick Smith Tandy, photo shops etc).

Mickoking is right on the money. Ok the Dob mightn't "look" like a real telescope, but believe me it is far more a real scope than the 76, and you will get far more pleasure out of using it. Plus a 6" Dob will show you far far far more deep sky stuff than that 76 ever could.

Davelrkn
25-06-2006, 09:54 PM
Hi
I would like to support the two previous posts
My advise to would be to stay well clear of the 76mm scope
My society here in Brisbane have been running nights for the general public twice monthly for the last 7 years.The number of times we have had to attend to these types of scopes were the first timer brings one along to these nights, and try to teach them how to use the scope that either has a wobblie mount or cheap plastic eyepieces with bad eye relief can put you behind the eight ball let alone start to show them the night sky

My advise as the previous posts suggest is to find a Society and have a look at the Dob and at least ask if you can have a go with one.

You will be surprised with the ease of use of the Dob, as there is no setting up just sitting it down and start observing.With the Equatorial the scope has to be roughly polar alligned for visual and also the scope has to be balanced.
Regards
Dave

rmcpb
26-06-2006, 09:45 AM
All the above advise is really great and you should try to get to an observing session before parting with any hard earned. In the mean time get yourself a pair of 7x50 binoculars, a red torch and a planisphere and start getting to know your way around the sky.

Cheers

ving
26-06-2006, 10:04 AM
hi peter :) welcome aboard!
where in sydney are you? I have a 76mm reflector like that one which i am trying to sell for a friend... but thats another story. the mount is wobbly as and its only good for bright planets and the moon. I wouldnt go there if i were you :)
try and squeeze another $100 out of your budget and get the 6" dobsonian... yeah i know it looks ugly but it will out perform the 76mm by 1000%. trust us, we are not trying to lead you astray, nor are we trying to get you to part with your hard earned cash. we just want you to enjoy looking at the sky :)

smenkhare
26-06-2006, 12:07 PM
Thanks for the replies all.
I'll have a look at some of the suggestions.
On the dobsonian mounts, how do you tell where the scope is pointing?
ie. i discover a new planet, how do i tell NASA/CSIRO where i'm looking?
I'm in Loftus and already have a pair of binoculars.

janoskiss
26-06-2006, 12:17 PM
You use a finderscope to point the scope. You make note of nearby stars and refer to charts for precise location. With a tripod mount it works the same way. Those setting circles you see on EQ mounts are a rough guide at best. I don't think most people use them.

You can also attach a computer like the ArgoNavis system to a Dob, which will give you instant readout of where the scope is pointing.

ving
26-06-2006, 12:28 PM
like steve said, take notes of nearby stars, take notes, even draw wht you see i guess. :) but really for your price range the 6" is going to be most practical in every sense.

Starkler
26-06-2006, 12:57 PM
Geez they have product warnings on all manner of things, why not cheap telescopes ?

WARNING: This wobbly frustrating piece of junk is not suitable for viewing the night sky.
It is designed to catch unsuspecting newcommers and to actively discourage an interest in astronomy by making it too hard.:screwy:

Yes the tripod mount looks cool and makes it look like a real telescope, but what may look sturdy enough in the shop becomes a wobbly resonating contraption once those shakes are magnified at the eyepiece by 100x or more.

Geoff
30-06-2006, 07:41 AM
Hi,
I thought I would add my 2 bits of advice.
I did'nt like the DOB when I first started just over 6 months ago, so I bought a Celestron 9.25 inch on a HEQ5 tracking mount. not a goto.I got sucked in with science. A very nice outfit. Expensive though.
The disadvantage is set up time, about 15 min at best. And it is difficult to point straight up and work. Even with a diagonal. And in a suburban back yard most viewing is up high. Which is better anyway.
I bought a 10 inch Bintel dob and modified the mount for smooth action.
The advantage is very quick setup (2 min.), Easy viewing straight up (I built an ajustable stool also as my back is bad) I have a red dot finder and a Rt angle finder mounted fairly close to the eyepiece holder so I can move from one to another easily. I can find things quicker with my DOB, and move to other areas faster and easier than the newtonian.
The DOB is a great all round scope. But for photo's and intense studying, the tracking mount is great, but is must be a good one, not a cheap wobbly as described above.
Regards
Geoff :)

dhumpie
30-06-2006, 02:08 PM
Hi Peter,

I had one of these and while I would not recommend them, they are also not half as bad. I saw a lot of things through my 76mm newt (the ring nebula and the dumbbell nebula for one and also some resolution, with averted vision in the Ara and Pavo globs). The problem is the aperture is too small to see any significant detail and you will soon be wishing you had something bigger. From experience, I say start with at least 6" of aperture. There is something magical about that size scope and it allows quite a fair bit of detail in globular clusters and galaxies. If you were looking at an equatorial, I say go for the 6" f/5 GS EQ. If you were looking at alt-az mounts, the dobs are the way to go. Since Andrew's raised the price of their 6" GS dob, I will be more inclined to pay a little bit extra for an 8". 8" buys you 78% more light grasp over a 6" and most globs will be resolved to the core in an 8" dob.

Just my 2 cents.

Darren

xelasnave
30-06-2006, 02:39 PM
With the 76mm there will be no hope of finding a new planet.. but with the 6inch you are bound to find a few...
Mate drop your preconcieved ideas and go the dob... and I would imagine Loftus is reasonable in the light pollution department so you will have a ball.
The 76mm by itself is good for a finder scope or a guide scope I have a 70mm and it is cool for that, unless you are going to do photography go dob...if you are going to do photography please realise that then it is all about the mount.. start at $2000 mount only and from there would you believe you reach $10,000 real fast ....$30,000 for mounts? oh yes.
Mind you the 76mm on a $30,000 mount could work.
Good luck I wish I could have got the advice herein before I started believe me. btw dont make one the parts will cost you more than the completed unit.. if you ever complete it.. I started a 235 mm and it was too expensive to complete so I got a finished dob instead.
alex

Soldant
30-06-2006, 11:45 PM
Honestly, I'd say go with the dob as well. There is nothing more frustrating than a poorly designed mount. You don't want to be messing around with terrible mounts that wobble/have slack controls, especially if you're new to astronomy or it's your first telescope. I had an EQ mount made in hell (actually it was made in Poland, as was the telescope, which was also quite poor) and I ended up breaking it and taking the rest of the tripod, which has various other uses.

If you're starting out, go for a dob. It'll give you much better views for an excellent price. Really, who cares what it looks like, if it works better than the guy who spent a boatload on the "real" telescope, who's laughing?

smenkhare
01-07-2006, 08:37 PM
As mentioned in my other thread, I plan to study astronomy also.
so is it worth getting a dob and then upgrading to something else? or just get a better one from the get go?

janoskiss
01-07-2006, 10:43 PM
Ratio of the cost of an astrophotography setup and the cost of a Dob is roughly 10:1 for a given telescope aperture. So start with the Dob. :) If you get a 6 or 8" you can always put the tube on an EQ mount later - ditto 10 or 12" Dobs, but they will need much heavier and more expensive mounts. Dob is easier and quicker to setup, so many people prefer it for visual astronomy.

smenkhare
02-07-2006, 10:41 AM
so i can just take the dob scope off and put it on a different mount when i'm ready to move up?
ok.
i'll look look at the 6inch Guan Sheng one.

Davelrkn
02-07-2006, 10:54 AM
Hi There
As mentioned in my other post above.The Dob is a unit that is well used and probably will out number the equatorials at astro camps ect.
They are so cheap (price wise) at the moment and have seen 20cm going for around the $500 mark when 10 to 15 years ago you could expect to pay that just for the mirror and for the complete optical tube assy( OTA) not much change out of $1000 and then extra for the mount.The big light buckets 16'' and above are Dobs why price and portability
Have recommened to plenty of people over the years to go with the Dob and they have not looked back.
If visual for the moment is what you intend to do with your scope then I still like many other posts here, go with the Dob

Regards
Dave

janoskiss
02-07-2006, 10:57 AM
You can move the OTA from between the two mounts as you like. Ving's 8" is looking good on an EQ: http://www.iceinspace.com.au/forum/showthread.php?t=6156

astro_nutt
02-07-2006, 11:06 AM
Hi Smenkhare!!...:welcome: good idea..with the dob mount you'll be able to move around the sky fast!..great for learning the patterns of stars which form the Constellations.:thumbsup: A 6" is a good learning scope..and later you can set it up on a good sturdy EQ5 or EQ6, (should you update to a larger scope, say a 10" then this will save you buying another mount!), with the appropiate tube rings and adaptors!:D

smenkhare
02-07-2006, 11:16 AM
EQ5? EQ6?
tube rings?
In english?? :-):help:

janoskiss
02-07-2006, 11:32 AM
For photography you take your OTA (optical tube assembly or simply the telescope tube) and stick it in tube rings (http://www.myastroshop.com.au/products/tuberings.asp) which you attach to a dovetail plate (http://www.myastroshop.com.au/products/details.asp?id=MAS-148) which goes on an EQ mount (http://www.myastroshop.com.au/products/mounts.asp). :)

astro_nutt
02-07-2006, 11:37 AM
Oooops!..sorry Smenkhare..an EQ5 or EQ6 is a heavy-duty German equatorial type mount on top of a tripod, (you'll find them advertised in the astro mags). This type of mount, when proplerly set up, will allow you to track celestial objects either by hand operated slow-motion controls, or with a motorised unit. This would be preferred for astrophotography. To convert a dob optical tube to fit an EQ mount, a pair of rings clamped around the tube is then fitted to a dove-tail mounting plate then attached to the top of the mount. Again, check out the mags and see how it looks.
A lot of guys in the astrophotgraphy section use a type of EQ mount, some have even engineeered and built their own! Cool stuff!