Dobsonian Advice

[JPete]

Hi there, my 9yo son has become obsessed with astronomy and we have exhausted the binoculars and we are ready for a scope. We have been considering our options and i was hoping for a sanity check on the forums

We are in the under $800 price bracket, we are semi rural and will do 90% of our observing in the backyard.

We camp and go bush quite a lot so being able to take the scope every now and then would be great.

We arent all that worried about photography yet (maybe iphone down the eyepiece for now ).

We want to be able to explore everything easily and clearly. Solar system objects, nebulae and galaxies in as much detail as possible.

Am i right in thinking that our next bang for buck is going to be a collapsable dob, saxon/skywatcher brand? I am probably not far off a 10" model for our budget.

I realise there is quite a few options at this price point, especially second hand, but once i move away from the dobsonian (and still maintain decent aperture) i guess it's super low end cassegrain or large and not as portable newtonian?

Does it sound like i am half on the right track?

Appreciate any thoughts or comments

PS: yes we are members of the ASV and we will be going to a few star gazing nights...but in the meantime i am keeping my eye peeled for a bargain

[barx1963 (Malcolm)]

Hi JPete
Firstly as you are ASV members I would enquire about the Loan Scope scheme they run. When I did it you get an 8" dob for $10 plus $50 deposit (Prices may be out of date now as it was in 2008) plus 2 eyepieces and a star chart for 3 months.
Great way to see what a decent scope can do without parting with your hard earned. At 8" they are easy to transport so great value for triops away.
If you are going ahead with buying, a 10" collapsible dob is great value. Compared to all other options, dobs give you the most aperture for the $. When you mention Newtonians, just to clarify, a Dob is still a Newtonian, the difference between a dob and other Newts is the mount, not the scope! With all other options you are paying for more expensive mounting systems.

Malcolm

[JPete]

Thanks...i have enquired about the loaners from them.

Yep, i get the difference. I guess i am just trying to make sure that for what i want to do i am getting the best value.

I see a lot of smaller refractors for the same dollars...do people buy them cos they can afford the fancy mount so they can take longer exposures to compensate for less aperture?

Does anyone know of any comparo pics of stuff through different sized scopes? There is reams of stuff written about them but it could be easily explained to us noobs by pictures i reckon

[Forgey (Paula)]

Hi JPete,
I have a 10" Dob and you are welcolme to come and have a look at to give you an idea, im in Cranbourne. Otherwise the Mornington Peninsula Astronomical Society http://www.mpas.asn.au has public viewing nights the next 2 fridays at 8pm at The Briars which i'll be there with my dob.

[barx1963 (Malcolm)]

Refractors are mainly used for imaging these days. A good refractor makes a fine deep sky scope, with no central obstruction you can get really nice contrast in your views. However most visual observers still prefer the aperture that a big dob can provide. It is simply bang for buck!
Obsessions web site has a comparison of an 8" to their bigger scopes starting at 12.5" here http://www.obsessiontelescopes.com/index.php I am sure there are other sites but no aware of them.

Malcolm

[wavelandscott (Scott)]

A refractor can be a nice scope but to me visually it is about capturing as much light as possible. In this respect in terms of bang for buck a reflecting scope is hard to beat. A refractor that can capture similar amounts of light is expensive.

[JPete]

Thanks for the tips, feel like i am on the right track...now to find a good deal.

Will see you are the Biars on Friday, thanks for the offer, look fwd to it.

[JPete]

Is this a realistic comparison? http://www.telescope-simulator.com/i...ware&Itemid=58

[Poita (Peter)]

Not really, all that is showing you is the field of view and magnification and different focal lengths and different powered eyepieces.

Youtube is full of 'through the eyepiece' videos.

If you look for something like Jupiter C8 etc. you will see videos through actual scopes which are pretty representative of what you will see.

[CarlJoseph (Carl)]

Hiya Pete,

Did you end up getting to MPAS last night? I heard the skies cleared and they had reasonably good seeing. Sorry I didn't end up making it myself.

Cheers,
Af (Carl)

[JPete]

No Carl, didn't go. It really was quite cloudy so we pulled the pin and had a BBQ with friends instead