New user weighing up options...

[bobban]

Hi Everybody

Complete newbie here. Have basically never done any astronomy although genrally interested in space/maths/science etc. I recently started playing with Google Sky Maps and was amazed how easy it was to recognize planets for the first time (could see Mars, Jupiter and Saturn last night at the same time last night). I had a vague idea before this they could be seen with the naked eye but am amazed how bright they were.

I want to get a telescope to see more. I am sure this has been asked too many times but I need help deciding what to buy. As you can see my interest is tickled and I really just weant to see some nice stuff in detail. Moon, planets, some deep space stuff just anything that is out there, and impressive.

So did a lot of research last night but still drowning in options. Money is flexible I want something kind of decent I would think budget anywhere from $200-$700

I was leaning towards the GSO 8"DOB for $499, mainly because they are well recommended here

Also considering the recommendation here in the Au/NZ section. I can't even find any shops with the iOptrons mentioned but can find the Saxon 8" DOBs. In general I read some people advising new people to avoid computerised and put the money into the optics althought I am a bit torn on that. I kind of think it will help me find a lot fof things much quicker but at the same time it might feel a little more organic and rewarding (and hopefully not too frustrating) to have to locate things myself.

If anyone can give me some advice that would be much appreciated.

[cometcatcher (Kevin)]

Welcome to the forum. 8 inch dob is a good choice but... I'm wondering if your expectations may be a little high. I know mine were when I first started. You will see the moon in great detail, Saturn's rings, Jupiter's moons and a couple cloud bands, but the planets though bright are still small through the scope. And as for deep sky sky, well we like to call them faint fuzzies.

Could I suggest finding a nearby local astronomy club that has a viewing night to get a feel for what various scopes can do first?

[The_bluester (Paul)]

That is probably great advice. If you can get to a local meeting you are likely to get a look through various types of scopes to see what works for you. The best thing is though that you can see if it really does fire your imagination at the cost of only a nights sleep before you hand over the hard earned.

All that said, a Dob of about 8" or more apeture does seem to be the default setting when first scope advice is asked for. My first scope experience was with a 4.5" newtonian (Same basic scope as a dob) on a german equatorial mount at 14 years old. Despite having no experience in setting the mount up (But some basic idea) meaning it was pretty hard to use, I chanced a glimps of Saturn on the first night completely at random and I was hooked. If it was not for that chance sighting I would probably have given it up as a bad joke after that first weekend.

Dobs are easy to use, easy to use is good! Cold and frustrated is a good way to go sour on the idea.

About the only other way to have real "Easy to use" is the computerised scopes like I have now but you pay a big premium for the sophistication of the mount and if you go small in apeture to claw back that cost premium then you stand a good chance of ending up frustrated again.

I really do like my current scope (Though work and life in general means it does not see the sky as often as I would like) but there are times I would love to freedom of just carting out a big dob, having a beer while it cools down and then pointing it wherever I like without electronics getting in the way of things.

[jenchris (Jennifer)]

Look up SAS.org.au - they meet at Ormeau (just south of Beenleigh) next week (you can pick up the times from the Ezine online).
Or the Brisbane Club if you're Northside - don't know when they meet.

[pw (Peter)]

A pair of good binoculars will increase your enjoyment of the night sky too.
Some 10 x 50 or 8 x 42 will work well & have more general use too.
Your idea of an 8" dobsonian mounted reflector is a sound one.

[julianh72 (Julian)]

Originally Posted by The_bluester

My first scope experience was with a 4.5" newtonian (Same basic scope as a dob) on a german equatorial mount at 14 years old.

Me too!

I suspect that for many of us "of a certain age" (born in the 1950s or earlier), our first magnified look at the night sky was through a pair of 7x50 or 10x50 binoculars (STILL a "must-have" investment for any stargazer!), and our first "real" telescope was a 4 1/2" f10 Newtonian on an equatorial mount (probably "Tasco" branded).

My father bought one in about 1975 or so, and it was the family telescope for the next 25 years. (And still worked perfectly, with perfectly acceptable optics, when we sold it about 15 years ago.) If I recall correctly, it cost him something like $400 back then, which would be a couple of thousand in today's money. Look at what you can get for ~ $500 - $1,000 today!

[bobban]

Just come home to read all these great replies thanks everybody. I will try and find a local astronomy club and see if I can join for a night to check out some equipment in action first hand.

[The_bluester (Paul)]

Originally Posted by julianh72

Me too!
I suspect that for many of us "of a certain age" (born in the 1950s or earlier), our first magnified look at the night sky was through a pair of 7x50 or 10x50 binoculars (STILL a "must-have" investment for any stargazer!), and our first "real" telescope was a 4 1/2" f10 Newtonian on an equatorial mount (probably "Tasco" branded)

I am a little younger than that, and actually I have not yet got around to some good binos, maybe this year.

And in my case the 4 1/2" newt was a Meade that my secondary school had, to my knowledge I was the only student ever allowed to take it home, probably one of the very few to actually use it at all in fact.

[bobban]

So I visited the Brisbane Astronomical Society's public viewing night at Mt Coot-that. I got to spend about an hour with a very nice gentleman called Chris who recently joined the club and owns a nice Bintel 10" Dob. This was his first scope so it was ideal to hear how he was handling it (very well!) and what he likes and dislikes about it. I got to ask him a zillion questions and he talked me through various adjustment procedures and many aspects of how it works. He was really a wealth of knowledge for someone in my position having just taken the leap himself. Bullseye!

He was thinking 8" but decided to go the extra size unfortunately nobody else had a 8" for me to compare. I'm sure this is a good choice for me but now I cannot decide between 8" and 10". The 10" looked good although a tad bulky. It is also an extra $200 which is possible but stretching the budget. Just not sure how much I would sacrifice by going down to 8". Can anyone advise me on on that?

[jenchris (Jennifer)]

The light getting into a scope increases as the square of the radius.
so 8" would be 4x4=16, 10" would be 5x5=25 so the ight would be about 1.5 times as much - which is quite an increase for a couple of hundred dollars.
I'm not a personal fan of 8" Dobs - they seem a little cumbersome for the size of mirror - whereas the 10" is a definite wow.

[pw (Peter)]

See if the 10" fits in your car for transport to a dark sky site.

[AstralTraveller (David)]

You'll find that the 8" and 10" are about the same length, the 10 is just fatter. This is because 8" are typically f/6 but 10" are generally f/5. You'll also probably find that length is the limiting factor for transport and storage. (Measure you car before you buy). I also went for the 10 and am happy with it.

[bobban]

Originally Posted by AstralTraveller

You'll find that the 8" and 10" are about the same length, the 10 is just fatter. This is because 8" are typically f/6 but 10" are generally f/5. You'll also probably find that length is the limiting factor for transport and storage. (Measure you car before you buy). I also went for the 10 and am happy with it.

Thanks for your comment. If the 8" is not significantly shorter I think this is another push towards 10".

Originally Posted by pw

See if the 10" fits in your car for transport to a dark sky site.

Chris from BAS mentioned that was the main thing that caught him out although he has managed to squeeze it in. Pretty confident form seeing his telescope it would fit in my car.

Originally Posted by jenchris

The light getting into a scope increases as the square of the radius.
so 8" would be 4x4=16, 10" would be 5x5=25 so the ight would be about 1.5 times as much - which is quite an increase for a couple of hundred dollars.

Thank you. I was more thinking just an extra 2" meaning just a little extra better but as you point out that is a significant step up.
I'm not a personal fan of 8" Dobs - they seem a little cumbersome for the size of mirror - whereas the 10" is a definite wow.

Chris had a Bintel which he said is a re-badged Orion which I have heard good things about. I also read someone else saying GSO are virtually on a par if not slightly better. I have found two places that have these and both have 10" for $699 (and 8" for $499).

http://www.bintel.com.au/Telescopes/...oductview.aspx

http://www.andrewscom.com.au/site-section-10.htm

[barx1963 (Malcolm)]

Originally Posted by bobban

Chris had a Bintel which he said is a re-badged Orion which I have heard good things about. I also read someone else saying GSO are virtually on a par if not slightly better. I have found two places that have these and both have 10" for $699 (and 8" for $499).

The Bintel scopes are actually rebadged GSOs!

Malcolm

[bobban]

Originally Posted by barx1963

The Bintel scopes are actually rebadged GSOs!

Malcolm

OMG thanks Malcolm!!

[doug mc]

The 10inch is not much more of a problem to handle. You may require more complex eyepieces to handle the f/5 over the f/6 of the 8inch. If you are older like me and have what are called floaters in your eyes, then the 10inch would have a larger exit pupil per magnification. That helps too.

[AstralTraveller (David)]

Well eps can be upgraded in the future. In fact, if you only have the eps that come with the scope you almost certainly will upgrade anyway. [Then you can have a whole new debate. ] In the meanwhile I'd take >50% increase in light gathering for a few seagulls at the edge of the wider eyepieces.

FWIW I have a Parracorr which I use on the wider fov eyepieces when using the 16" f4.5 but which I don't use on the 10" f/5. I've also noticed that different people find coma more or less annoying then me. I suppose that is true of all optical abberations.

[bobban]

Just wanted to update to say thank you to all who contributed advice. I ended up getting a 10" GSO Dobsonian from Andrews in Sydney (all up about $850 including shipping, collimater and Barlow lens). Unfortunately shipping was delayed due to Easter period and I missed the lunar eclipse but otherwise I have been happy with the purchase.

I was amazed that the first night I was able to unpack and commence stargazing thanks to the awesome tutorials Chris from the BAS gave me on his 10" dob. He must have a real knack for explaining things because somehow I remembered it all and in no time I was checking out Saturn and the moon and very impressed with the results. Definitely quite a big piece of equipment but it does go in the car.

Thanks again to the all the nice people on this forum. Happy stargazing.

[acarleton (Aidan)]

sounds great, congratulations on your purchase

[barx1963 (Malcolm)]

Bob
Well done on the purchase and glad it all worked out. Keep us up to date on how the scope is going and what you have seen with it.

Cheers

Malcolm