Help with a really REALLY stupid question!

[raven flame (Suzy)]

Hello IISers! I'm new to the board and new to stargazing and I desperately need help!

I am looking at buying my first telescope. I have lurked around IIS for a few weeks now gathering information, but seriously, I am as confused as I ever was!

Most people here appear to be fan of the 'dob', but after researching I think I might be better starting off with a refractor. I have seen IIS members talk about "6 inch and 8 inch" as desired entry level scopes. I know this is going to sound really dumb, but exactly what are you referring to? When I read specifications of various telescopes, I can't identify what I should be looking at in relation to the "6 inch rule"!

For example: http://www.ozscopes.com.au/celestron...telescope.html

This is one of the scopes that I had my eye on, but where is the 6 inches in the specifications???


I want to look at planets, moons, stars and nebulaes (although from what I've read, I may need a high quality (expensive) telescope for seeing nebulaes?)

I apologise for my ignorance!

[peter_4059 (Peter)]

Suzy,

The 6 inches is probably referring to the aperture (ie the diameter of the opening, mirror or main lens). The scope you posted a link to has a 60 mm (about 2.5") aperture. The reason a lot of people suggest a dob is because you get more aperture for your money than you do with a refractor. They are also much easier to set up than a typical scope on a german equatorial mount.

The scope you are looking at will be ok for moon and some planets but not great for nebulae as it has quite a small aperture so won't collect as much light as a larger scope.

Hope this helps!

Peter

[jenchris (Jennifer)]

Telescopes sold in USA usually have inches as a size
In Oz that is often in millimetres.
So a 150 will be a 6" - this is the size of the big end or mirror (showing the light gathering capacity.
For a refractor 6 inches (150mm) is the limit as they get too expensive after that.

diam area refractor ……….. area sct
2 ……….. 3.142 ………..
4 ……….. 12.568 ……….. 9.426
5 ……….. 19.6375 ……….. 16.4955
6 ……….. 28.278 ……….. 25.136
7 ……….. 38.4895 ……….. 35.3475
8 ……….. 50.272 ……….. 47.13
9 ……….. 63.6255 ……….. 60.4835
10 ……….. 78.55 ……….. 75.408

As you can see the light gathering capability goes up quite dramatcially at 8 inches.
A Dob at 8" will give you a great look at the sky - whereas a small refractor will give you good portability but not as much view.

If you go expensive you can add goto which will give you the added luxury of asking it to show you a particular patch of sky or object and not have to learn where it is or how to point
an 8 inch dob is about 6 hundred dollars an 8" refractor is 6 thousand

[raven flame (Suzy)]

Oh I see! Thanks so much for explaining! With your advice in mind I think I will reconsider the dob telescope then.

('Goto'... sound perfect for a dense like me!) Lol!

[torana68 (Roger)]

Originally Posted by raven flame

Oh I see! Thanks so much for explaining! With your advice in mind I think I will reconsider the dob telescope then.

('Goto'... sound perfect for a dense like me!) Lol!

your brain is infinately more powerfull , use the money you save on not getting a goto set up on something else. download "stellarium" and maybe join a local club?

[Jen]

Gday Suzy
to IIS

Now take it from a girls point of view go the DOB for sure the bigger the better (SIZE DOES MATTER)
refractors cost so much more unless you want to get into astrophotography then go the refractor but if your happy scanning the sky and enjoy looking at nebulas and galaxys etc.....go the dob for sure

I have a six inch reflector and i so wish i came in here first and got talked into buying a dob

Good luck and happy shopping

Jen

[tlgerdes (Trevor)]

Hi Suzy,

I will go against the grain here. Get GOTO. It will make your introduction to our world a lot simpler. If you set yourself $1500-$2000 as a budget you will be pleased with the results.

Something like this is great
http://www.ozscopes.com.au/skywatche...telescope.html

We started out with a Meade ETX 125, but this is what supercedes it nowadays
https://www.bintelshop.com.au/Product.aspx?ID=8480

Yes there is a learning curve to understand how to drive the things, but that is easier than learning celestial mechanic and where things are in the sky.

[jenchris (Jennifer)]

I went straight for an 8" SCT - I wasn't prepared to mess about trying to learn patterns inthe sky.
I did find that I learned fairly quickly, but I had the telescope teaching me -
I had the money and I'm immensely happy with my pretty little blue tube!

[Jeeps (Sam)]

If you're ok at spending over $1000 then definately get the GOTO but if you're looking to spend less than $1000 a dob is your best bet. You might want to allow some $'s in your budget for better eyepieces and a 2x barlow.

cheers

[Suzy]

Hi Suzy
(Another Suzy )

There are no stupid questions here, we all started as beginners.

Just beware aware that Go-To is expensive, and sometimes people choose this capability over aperture. As an example, and 8" with Go-To costs around $300 more than a standard dob. So for the same price, you could get a 10" and actually be able to see more. http://www.sirius-optics.com.au/orion dobs.htm

I'm an advocate of learning the sky manually for a beginner - many people say Go-To helps them, I don't doubt that, however, if you learn the sky the traditional way, i.e. maps/planeshpere/computer software (highly helpful, which Roger mentioned), you'll get plenty of help, albeit a bit frustrating at times, but brings about much joy and reward locating objects yourself, and you'll get to know the sky very well (this method makes you learn it!) - eventually you'll know exactly where to point your scope on many objects without the need for maps. Going slow in learning constellations & objects within them helps as opposed to going fast and trying to see as many objects as possible in one night with electronic help. For experienced observers, electronic help is very useful as they already know the sky and it's more a matter of not needing to waste the time.

Another option (and one that many do) is to buy the dob and later fit it out with Go-To. You'll get to learn the sky while saving up for it. I think total it costs around $1,000 for the complete kit for an Argo Narvis. Many here speak very highly of them and the support offered.

Just a bit of food for thought from another perspective.

[Suzy]

Originally Posted by Jeeps

You might want to allow some $'s in your budget for better eyepieces and a 2x barlow.
cheers

Well said Sam. The eyepieces that come with the dobs are okay, but you will eventually want to replace them, mark my words .

[Rob_K]

Well my advice is a bit different to most (as usual) Suzy. If you are just entering the hobby, go small and cheap. A small refractor (80mm minimum objective size) or a small reflector (perhaps 114mm). Ideally get an Alt/Az mount which is simpler and more intuitive to use - you move the telescope up or down, across or back.

Astronomy is an expensive hobby - we talk about a couple of hundred bucks as being nothing, but of course to a lot of people that's huge money, especially for a hobby! It is to me. We could take up origami or flower arranging at no cost at all!

A small scope will really deliver the beauty of the night sky - wider field views of the delights of the Milky Way, and a big range of the brighter interesting objects out there. If you want to see faint mag 13 galaxies right at the start then by all means go for the big dob though!

Small scopes are great tools for sharpening your visual abilities, and everyone's eyes do need training to get the best out of whatever scope they're using - it does take time, a long time. They don't represent a massive investment in something it might turn out that you're not interested in. They are portable, low maintenance, and unlike big scopes they can be taken outside and used straight away (no long mirror or tube cooling period). Refractors require no collimation (routine adjustment of the optical train) and small reflectors are much more forgiving in this line than large ones, only occasionally needing checking.

In time, and after viewing through a variety of scopes at club meets etc (recommended), you might decide that this star stuff is really right for you and you might want to go bigger (although not everyone does!). Then get a big dob, expensive eyepieces, GOTO etc. Your first scope will then serve a useful purpose as a travel scope, or for a quick set-up when you can't be bothered dragging out the big 'cannon' or polar aligning your two-tonne mount!

Good luck with it!

Cheers -

[NorthernLight (Max)]

Hi Suzy,

and welcome on IIS!

Since we are living in the post-Hubble era I think especially a beginners scope need to be as large as practicable/affordable.

Most people aren`t impressed by looking at stars and dim fuzzies as they don`t know what it actually is in the first place.
So what the newcomer wants to see is most of the time something like a Hubble picture - big and bright nebulae or highly detailed spiral galaxies.

A 80mm refractor wont show much in suburban areas and is in my opinion the choice for people who know what they want from it (and that is mostly imaging).

My advise is: get as much aperture as you can handle. My wife i.e. can`t handle a 12" newton but an 8" dobson mounted newton is not a weight issue for most women. It has a lot light gathering power - big-bright nebulae even from suburbia- and is easy to set up for the odd hour stargazing on say a wednesday night between 9 and 10.

I must admit that it is damn true what they keep praying here on IIS: "the best scope is the one you use very often" - and not necessarily the most sophisticated, that you can`t be bothered to assemble, power up, pol align- everytime you just want to check out Jupiter or the Moon!

PS: if you`re keen on GOTO but want to keep it simple and intuitive - check out the fork mounted SCT`s with all star alignment or light switch technology of Celestron/Meade respectively but again - get the 8"+ ones.

[Jeeps (Sam)]

Andrews is currently doing a Full GOTO 8" Skywatcher DOB for $999 at the moment. That's not a bad price at all. You get both a larger aperture and full computer automation & tracking.

cheers

[Jeeps (Sam)]

Also,

Orion does a 50" dobsonian for only $123,000.000. But that depends on your budget.





http://www.telescope.com/rsc/img/cat..._size_comp.jpg

[jenchris (Jennifer)]

That's right Jeeps - but that doesn't include the ladder to see in it, or the truck for carrying it.
You also need to hire a team to set it up and probably have to pay a rigger union rates to put the top on.

[Trixie (Carey)]

Hi Suzy,
I thought I would add my thoughts as I am a complete newbie to all this as well (by the way Im pretty sure I asked similar questions before I bought my telescope as well). I just recently bought an 8" skywatcher dob after cruising a few astronomy forums for a while. It is pretty heavy but I can still haul it around by myself if I need to.

I couldnt afford the goto setup and was a little worried I would suffer because of it as I knew about 3 constellations and how to find the moon and that was about it! Anyway I have had a great time with my telescope so far. I have been using stellerium, a star disk and a couple of books. So far I have been sticking to the easier to find things but that has kept me busy enough for the past couple of months and I am learning to find my way around the sky.

My favourite book (as a complete beginner) is A guide to the night sky. It was great because the starhopping chapter works through one section of the sky at a time. I found the other books a bit too complex for my level of knowledge at the moment. For the planets I have been using Stellerium, which I have been taking outside with me.

My only problem is hours seem to go by so fast and I end up going to bed really late!

[wasyoungonce (Brendan)]

I would add...as a newbie..go to Bintel (Melbourne) and look at the scopes. They are very helpful and will steer you in the right direction.

Plus you may need after market service or advice and the shop you purchased it from is the best place for this..thus a shop with a salesperson you can talk to..not an online shop.

[OneOfOne (Trevor)]

If you live down the peninsula way, the Mornington Peninsula Astronomical Society (MPAS) has their public viewing night this coming Friday, unfortunately the weather is not looking so good at the moment. We will have a number of scopes out if it looks like becoming clear, so you can have a look through a variety of types and sizes. I will be in the shed giving the talk.

http://www.mpas.asn.au/Maps.htm

Maybe I will see you down there.