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michaelh82
29-04-2012, 11:11 PM
Hi all,

I've always had an interest in astronomy but only in the past 12 months have I started looking into it more seriously and am now looking to get started.
Most important to me is something easy to setup and use so I will spend more time enjoying it! Generally I'd imagine most viewing would be done at home (which is currently in Adelaide, but likely to be Sydney soon). Astrophotography isn't really a priority to begin with (but who knows what the future holds).

I've read a lot of the threads posted here and have come up with a few ideas, total budget with accessories around $2,500. Prices from http://www.andrewscom.com.au/site-section-10.htm .

Sky-Watcher Reflector - 200mm on a HEQ5PRO - $1,499
http://www.skywatcher.com/swtinc/product.php?id=64&class1=1&class2=104

Sky-Watcher Refractor - 150mm on a HEQ5PRO - $2,099
http://www.skywatcher.com/swtinc/product.php?id=38&class1=1&class2=103

Sky-Watcher Dob - 200mm GOTO - $1,199
http://www.skywatcher.com/swtinc/product.php?id=170&class1=1&class2=106

My current thoughts are that the Sky-Watcher Reflector with the HEQ5PRO is hard to beat at $1,499, and if I wanted a Refractor later I could just buy the OTA and swap them over as desired. The cost of the Reflector isn't much above the Dob either, so I feel as if the mount is really only costing $300.

Am I on the right path or am I overlooking something?
Is there any reason to choose a refractor over a reflector?
Would a Dob be easier to setup and use than the other options?

Any other thoughts or suggestions are also welcomed!

Thanks :)

barx1963
30-04-2012, 12:15 AM
Hi Michael.

You have obviously done some research. All 3 scopes are not bad. The thing to remember with an EQ mount like the HEQ5 is it is not the easiest to setup. It MUST be polar aligned at least moderately accurately to be useful even for visual use. Also on a Newtonian on an EQ mount you will often find the eyepiece is some body contorting positions.
Refractors with a diagonal will usually work better on an EQ mount as the eyepiece position is friendlier BUT you end up paying more for a smaller aperture.
IMHO the dob is usually the best choice. I note you have selected a GOTO dob. This will require you to learn the setup procedure, as long as you are comfortable with that go for it. The only thing with GOTO is you are trading aperture for the convenience of GOTO. In my opinion, aperture should always win. I know from practical experience that for many objects I can find the quicker with star hopping and other with GOTO can get them, but you have to learn the night sky with can take a while.

Anyway, good luck with your choice. Oh and by the way, I have purchased from Andrews and was very happy with the service.

Malcolm

Wavytone
30-04-2012, 01:57 AM
Yes. What do you want to use this for ? The optimum scope for you depends on what you do most of the time, and there are distinct categories:

a) if you are mainly into casual visual observations of whatever is 'up there', aperture is king and you don't need an equatorial mount. For this the ideal scope is a cheap 10" f/4 dobsonian. This will give you good views of the bright nebulae and galaxies for a start, but somewhat disappointing when it comes to high magnification on the moon and planets.

b) if you are more interested in high-magnification views of the moon and planets but don't care so much about nebulae and galaxies, then you want a long focal length and a cheap mount that will track well enough for visual use. A good all-round starter scope is the 20cm f/10 SCT such as the Meade Lightswitch, and easily in your budget. You could also consider an f/15 18cm Mak, but adding a decent mount within your budget will be a problem.

c) if you really are itching to try astrophotography you'll need an f/7 refractor and an EQ6 mount, and an auto guider. A 10-15cm APO is within budget, but for visual use this scope will be quite disappointing.

d) Think carefully about eyepieces. Many waste a lot of money by buying cheap junk eyepieces, then realising they're junk, spending more to buy a midrange set, then finally winding up spending even more to buy 2-3 really good ones (which they should have done in the first place). The other thing is that price isn't always a good indicator of quality; some low-cost eyepieces perform very well.

Lastly, think about buying secondhand - your dollars will buy a lot more. Not just here - www.astromart.com and www.cloudynights.com are also worth watching.

dannat
30-04-2012, 07:06 AM
If you want easy to setup then the dobsonian or an Alt/az mount will be easiest

MattT
30-04-2012, 08:53 AM
Hi Michael,
I have the 8" reflector and 6" refractor scopes on the HEQ5pro mount. Took me the best part of a year to learn how to set up the mount. I prefer the refractor to the reflector. I was often up a ladder in all sorts of positions with the reflector and lying on the ground or sitting with the refractor...which is much better than up the ladder.For times when I want to get out there quickly I recently got a manual EQ5 mount (hand control no power needed) and a 4" refractor which I pick up and move around easily set up in under a minute, so much easier to use.
My advice... get a 10" non goto dob(or one that is goto but also can be used by hand) and enjoy the sky with simple ease. 10" gathers 50% more light than a 8" I think:question:
Cheers Matt

jjjnettie
30-04-2012, 11:23 AM
Quite a few of us here started with a 10" non goto Dob. Big aperture and no fuss setting up. You can even catch some happy snaps of the Moon and Sun (properly filtered of course) and Planets through it, by butting the camera lens up to the eyepiece.
The fact that it's significantly cheaper than the one's that you were looking at, means you'll be able to buy yourself a Barlow lens, a collimator. Any money left over can go towards a quality eyepiece down the track. The eyepieces that come with the scope will serve you very well to start off with.
I'd advise attending an open night at your local Astro Society. There you'll see a range of scopes and have a chance to look through them and see for yourself their individual strengths and weaknesses.
Personally I'd steer clear of EQ mounts for the time being. You want to enjoy the experience at this stage, not dread the setting up and aligning process.

michaelh82
01-05-2012, 07:35 PM
Hi,

Thanks for the replies.

I am not 100% sure the type of viewing I wish to do. Planets are a good place to start, but obviously the numbers are limited compared to other objects, so I don't think they should take priority.

I have looked through a few telescopes, but they have all been SCTs from memory.

Appreciate everyone's thoughts. I have ruled out a Newtonian based on size and how difficult it may be to use (ladder and ground don't sound appealing).

As the cost of the refractor is high, I thought a Meade LX90 8 inch might be worth coming up with the extra money for ($2600 currently). This would appear to solve the setup issues with an EQ mount and it seems quite transportable if I ever want to move it elsewhere.

How is a non go-to dob? Is it really that simple to just point it somewhere and find something for beginners? Just concerned that I'll get frustrated and wish I had bought a go-to. Although at $549 the cost is very appealing.

Thanks again.

AstralTraveller
01-05-2012, 08:14 PM
You won't need a ladder for a 20cm scope - it's only 1.2m long. In fact what you will need is that most valuable observing aid, the adjustable observing chair. I have a refractor and like it but overall aperture is king. Get a dobs. Get a big one.

BTW a hidden added cost with the refractor is the focusser. The standard Synta focusser is not ... ah ... particularly useful (not unless you have some papers which are about to blow away). The act of moving the focusser will shake the image so much you'll find it hard to get an exact focus. I almost immediately added an aftermarket motor drive to the focusser which made a huge difference. However after a few years the poor excuse for a tube guide wore out and the image shift became more than unpleasant - it was unusable. So I added a moonlight focusser (worth about the same as the OTA) and it's now beautiful. I can see stars perhaps 0.5 mag fainter than I could with the inferior focussers. You won't have nearly as much problem on a newt because the mounting is more stable.

barx1963
01-05-2012, 09:32 PM
Michael
The LX90 is not a bad bit of kit but pricey for an 8" scope. Remember if you are transporting it you will need power, either a nice big battery or mains.
My main prob with go to technology is that is just one more thing to go wrong. I have lost count of the number of people at camps and observing nights with gear that spend all night trying to get it working intead of doing what those of use with dobs are doing .... observing.
Its not to say they don't have their place, but for a beginner they are not always the best choice.
The LX90 still needs aligning, while a 10" dob you just put on the ground and start observing.
Naturally, you will need to learn your way around, when I started with an 8" dob it took 3 or 4 nights before I was comfotable with navigation, and with time you get better. It is a skill that needs working on, but it is very rewarding.

Malcolm

Peter.M
02-05-2012, 09:02 AM
When I first got my telescope I didnt have the attachments for my camera (which was why I got the scope) so I decided on doing some visual work while i waited. I have an EQ mount so setup was not easy for a fresh beginner and I ended up undoing the clutches and using my mount as a push to. The fact is that to get goto to work you will need to know and be able to point to certain stars, by the time you learn where these stars are in the sky you probally have familiarised yourself with star charts. When you know how to use star charts you are well on your way to finding your own DSO's. Some people buy goto and then get frusterated with setting that up. So you need to decide where you want to spend your time (starting) working out that your hand controller uses the american date format, or looking around the milky way for that elusive glob cluster omega cent.

The setup may be different with goto dobs, but your still going to have to learn where the stars are.

alistairsam
02-05-2012, 11:39 AM
I agree with Malcolm, the more technology you have, more areas for failure even if it is rare.
you can always get a non-goto dob and use good printed setting circles to locate objects. no power required and you learn the night sky and you'll learn star hopping as well.
Most of the Dob's do come with printed Alt and Az setting circles and once you know how to use it, it becomes very easy and stress free.
It can be frustrating to manually locate objects in the begining, but that's part of the fun, cause the elation you feel once you've located it manually is really good.

Aperture also helps. A collapsible 10" non-goto is a good start IMHO.

I've got an EQ5 pro, and while the goto works well most of the time, you have to get an accurate 3 star alignment to start with and it can always vary which makes you want to correct it or align again and so on. A reflector on a GEM is not neck-friendly.

A Dob for planetary can be a bit frustrating if the mount movements are "sticky" and you're at high magnification as you need to keep adjusting to follow the planet and you might have difficulty making small adjustments. Good eyepieces help a lot as well. There are lot of threads here where people have improved movement on factory shipped Dobs.

I haven't seen many people using refractors for visual and what their experience is, but you might want to do some research on that.

niko
02-05-2012, 11:55 AM
I, like many here, started with a dob (8") - loved it and learnt the sky. Seeing the rings of Saturn through it for the first time is something never to be forgotten. They have great re-sale value too.

So, I'd recommend the biggest aperture dob you can afford/manage and use any left over cash for eyepieces down the track as mentioned previously. Try as many out as you can before you buy. They are expensive but worth it if you pick the right one for you.

I progressed from the dob to an alt/az mount and then to the EQ5. The EQ5 still frustrates me but I'm slowly conquering the challenge. I don't use it for visual - only photography. I now have a 10" dob for visual and showing the others the wonders of the sky.

Everything I own I bought secondhand here and have never had any complaints and I saved a heap of dough (only to spebd it on other atsro bits and bobs, of course!)

niko

andyc
02-05-2012, 05:54 PM
I'd suggest saving your $$$ and going for a non-goto Dob myself, but then I'm very much a visual observer and number of photons matters more than GOTO capability for me! I started with a little refractor then moved quickly onto an 8" dob, and that gave me many years of quality observing (in Scotland), and could easily fit into the car for travelling to a darker sky site. I've loaned an 8" scope here in Oz and it's quite enough to track down a lot of the objects on John Bambury's list of 600 southern skies deep sky objects.

The pros are: speed and ease of setup, low cost (meaning plenty spare cash for good eyepieces and any other accessories), and little to go wrong. Speed of setup can't be underestimated, especially if there's a high chance of clouds or other distractions. The only significant mechanical problem I ever had in 20 years observing with my Dob was my secondary detaching from its mount and colliding with my primary mirror around the 19th July 1994 :eyepop:- I remember that because it was my first chance to observe the impacts of Shoemaker-Levy 9 onto Jupiter! Much swearing and a hasty repair later I did get to see the amazing impact scars, before sending the chipped primary and secondary for repair a few days later - I got a new mirror free as it was the glue holding the secondary to the holder at fault :D - but this is certainly not a common problem!

The cons are that you will have to learn about the sky a bit in order to find the things you want to look at, but this is surely a good thing, right? By finding your way about the sky it'll become like an old friend each time you see it, and you'll get to find all sorts of hidden gems, and get the rewards of successfully star-hopping to a good deep-sky object! It gives you a much better 'feel' for how objects relate to each other in the sky, which is absent if you just type in the number and press 'go'. You will also need some star charts, ideally those that show down to 8th mag stars or so, as they'll be the ones that show up in a 30mm or 50mm finderscope. 6th mag will do for finding a fair few obects, especially as you learn the constellations (if you're not already familiar with the main ones). A magnifying finder is pretty much essential from suburban skies, where fainter stars are not visible for the zero-power finders. If you don't like the idea of star-hopping with charts (e.g. if you find map-reading a nightmare then lots of time with star charts may not be ideally for you?), then obviously a goto scope will largely eliminate this need, so long as you know what you want to find.

But it all depends on what you want to look at of course!

Jen
02-05-2012, 07:39 PM
:D GO THE 12inch GOTO DOBBIE you wont regret it :thumbsup: and if you cant be bothered setting up the goto you can also use it manually and you can also have a go at some planetry imaging later down the track if you like :) happy shopping :thumbsup:

michaelh82
04-05-2012, 06:17 PM
Hi all,

Thank you very much for the insightful advice.
You have convinced me a non-goto Dob is the way to go, and this is of course well within budget. I do get to learn the sky and I suppose one of the points of a hobby is to develop new skills. The resale value is also appealing for when the inevitable time to upgrade comes.

So I think I'll go for an 8 inch Dob, plus the other recommendations in a post on beginner starter packs.

Thanks again!

brian nordstrom
05-05-2012, 01:05 AM
:hi: Good choice there Micheal , you will get years of enjoyement out of one of these .
Hope you keep us all informed as to how your new journey pans out , :thumbsup: .
Brian.

KG8
09-05-2012, 08:53 PM
I almost rushed out and bought what I thought was the right scope 6 years ago and luckily I went to an astro camp and spent a couple of nights watching people setup gear and using it. I had owned a 8" sct 20 years ago so I wasn't a newcomer from that perspective but I walked away from that camp with a whole new conception of what I wanted.

There will be a camp or an evening somewhere near you in 2 weeks at the new moon, just call a few local clubs. Choosing a scope to suit really relates more to your natural mechanical abilities. If you like tinkering, can fix a toaster and do a service on your car you may want something a little more challenging than a dob. Some people love them but to me I need more complexity, more of a challenge in my astronomy experience.

BTW, you can use any telescope manually. I often put a small celestron 6" atop a german equatorial mount out in the back yard with no more alignment than pointing it roughly south. I loosen the clutches and can pan around and look at anything, as easily as a dob would. If I plug a battery into it it will also track pretty nicely, agin with no special alignment needed.

issdaol
10-05-2012, 08:19 PM
I had a Meade LX90 for many years through lots of interstate moves. It is light and easy to carry and I never had any fault in all the time I owned it (over 8 years). Alignment was really easy: just point south select 2 star alignment and less than 5 minutes you are running with full GOTO and it is pretty accurate. The good thing is if you want full manual control just turn the GOTO off.

MattT
11-05-2012, 12:38 AM
Hi Michael have you got a scope? If not... I said earlier to get a 10" Dob as did some others but if you want an 8" think about getting an optical tube and putting it on an eq5 motor driven mount that can also be manually used.These come up in the classifieds all the time. KG8 knows what its about.

Its really easy to set up a manual eq mount in 1-2 mins and have the the scope tracking objects with motor drive. I have just come in from doing just that... Saturn was very nice before the clouds rolled in, but thats Melbourne! Plus you get the added benefit of learning to use the setting circles just like the old days:thumbsup:

:hi: Matt

KG8
11-05-2012, 06:00 AM
I loved those old days matt, there was something exciting about having the star atlas beside you and adjusting the old fork mount meade via the big setting circles. The controls were beautifully smooth and accurate. An 8" fork mount sct comes up for sale here from time to time and cheaply too, if I didn't have so many scopes....

MattT
11-05-2012, 05:43 PM
Yeah the good old days....I learnt on a 3" Unitron in the late 70's really wish I could have it back:sadeyes: I prefer the manual eq5 to the goto version, just dead easy to use and can still find things with the setting circles, the only batteries are 4 size D ones....less is more! I'm only visual though with no thoughts to go imaging. Matt

ausastronomer
11-05-2012, 05:59 PM
Hi Michael,

I certainly could not argue with that choice. It would be my 2nd choice. I would however recommend a 10" as a better option, over the 8". For a bit more money you get a lot more telescope. Two inches extra aperture may not sound a lot but on globular clusters and galaxies there is a significant difference. A 10" telescope gathers 56% more light than an 8" telescope. IMO an 8" is the largest of the small telescopes and a 10" is the smallest of the large telescopes. In the interests of portability/storability and transportability I would give consideration to spending a little extra money and getting a 10" Meade Lightbridge which is a rebadged GSO semi truss scope and very portable, or a 10" collapsible tube Skywatcher.

Cheers,
John B

Aidan
12-05-2012, 01:26 PM
I am in a similar boat. I am turning 30 this year and as a present I am looking at a new scope.

http://www.ozscopes.com.au/dobsonian-telescope-skywatcher-black-diamond-collapsible-10-inch.html

Any thoughts on this, or does any one have one the same or similar?

Pros/cons and price?

thanks as always

Aidan
12-05-2012, 01:31 PM
Further to last how would this go for basic astrophotography?

Thanks again

ausastronomer
12-05-2012, 02:50 PM
Hi Aidan,

It could do limited photography of the moon and bright planets that is all. If astrophotography is on your agenda their are better options.

As a visual telescope this would be my first choice on the basis the 10" Meade Lightbridge is no longer available in Australia. I just found that out when I went looking. Bintel have stopped importing the 10" version because the shipping costs are excessive. The 12" Lighbridge is only $1,099 and they are excellent.

I might suggest you consider a 10 or 12" telescope for visual astronomy and consider purchasing a small tracking telescope for astrophotography at a later time. You can use small telescopes for astrophotography they are usless IMO for visual astronomy.

Cheers,
John B

brian nordstrom
12-05-2012, 08:10 PM
:thumbsup: Hi KGB , yea I think almost all of us have (almost) made a bad descision like that at one time or another :rofl: .
Brian.

ausastronomer
13-05-2012, 08:09 AM
Well not quite as easily. I have been there and done that. When you have a 6" refractor on a GEM you need to stand on something when you point it down low and when you aim it up high, which is where I prefer to observe because the air is better, you are crawling around on the ground with the black snakes :)

Cheers,
John B

michaelh82
13-05-2012, 11:41 PM
Hi all,

Haven't purchased anything yet. In no enormous rush to do so as plenty of other things are going on just at the moment.

I'm going to stick with the 8-inch manual dob. If I really get into this hobby I'll be happy to upgrade later on to something more fancy (or 2).

Aidan
14-05-2012, 10:32 AM
Thanks John.

I think I will go with that one. the 12" is getting too expensive.

The expensive of Astrophotography will have to wait.

All I need to do is find a scope with a wine glass holder and I am set :)

Aidan

cjamo9
17-05-2012, 04:37 PM
i recon you could fit a nice little shelf on the dob mount but make sure you put it under the eyepiece holder.

Aidan
18-07-2012, 09:51 AM
Finally got my new scope 10" Dobsonian, first light last night really impressed .. It is a significant step up from my old Bushmaster Starexplorer...

Thanks for the advice and info on these forums, either directly or indirectly.