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spikeface
08-04-2008, 09:10 PM
hey all!

i've just asked this question in the beginners spot, but now realised it probably belongs here...

i'm about to buy my second telescope after being fairly dissapointed with a 130mm reflector... so i'm looking at buying at least a 12" dosonian... maybe a 14"... but i wanted to know a few things first...

How big can i go before i start running into problems such as..not being able to fit it in my car?( i have a sedan {ea falcon})... can you take the tube off the mount easily, or do dob's have to generally stay assembled? what are the best brands to be looking at? and finally... whats a good price? i have around 3K to spend...

so if any of you wise astronomers have a spare moment... you would make me very happy if i could get some help! bring myself and a dobsonian together for our first embrace! :D

omnivorr
08-04-2008, 09:45 PM
Hiya spikeface, :welcome: ..don't let the rush sweep you off yer feet..;)

that "$3,000" could buy you a brace, indeed a gaggle of Dobs!!...

...and much else besides. So take yer time , ... mebe a nice lil 8" or 10" to become familiarised with it... a basic one for $350-500, plus shipping...

or hold on and see if the other kinds of scope might better fit your aspirations. ...once the IIS extreme-enthusiasts have bent your ears to the many and splendid options abounding in more numbers than the dollars you'll ever have to shake at them :P;):lol::rofl::rofl:

don't blow ALL your Ccccchristmases at once :D

Cheers
Russ

taminga16
08-04-2008, 10:05 PM
A 10" Dob would go well in and out of your car and provide you with plenty of seeing, the telescopes from Bintel and Andrews are the same gear with different sales packages, aperture has never been less expensive! A 10:1 Crayford focusser is a good feature, some might gripe about the GSO Plossols, but they are a good start, If you have change puchase a Telrad finder, and hold onto the balance of the $3000.00 FOR AND EYEPIECE UPGRADE AFTER YOU ESTABLISH WHAT YOU NEED. Good Luck.

Regards,
Greg.

erick
08-04-2008, 10:38 PM
Hi Spikie

I can tell you that a GSO 12" tube will not fit across the back seat of an EL Ford. The distance between the molded door handles is a few cm too small. I think it will fit in an EA. The base is pretty big too. A bit of work with the tape measure will be needed before you make a final decision.

Eric :)

Blue Skies
08-04-2008, 11:58 PM
I think you need to get down to an ASSA meeting and check out other peoples' truss-tube dobsonians and ask them about the pros and cons of dealing with a big scope.

GrahamL
09-04-2008, 08:34 AM
hi :)

At least a 12" and 3 k.?. you can do a lot with that budget:thumbsup:

A lightbridge 16 " is doable with a little cash left over for a few accesseries

A lightbridge 12" , argo navis and two nice quality eyepieces
would also take care of most of your cash

A solid tube 12" argo and the eyepieces and a you have another few hundred left over .

gso ,and the meade lightbridge are made by the same company btw

I had a 10" for quite a while and it was a great scope
my only problem I had wasn't to do with the solid tube and its physical size
but the base ..my boot was a few mm off fitting in the assembled base ..
not a problem to take it apart or let it ride up front but still a ..pita..
all the same .

If you look at the 16" pictured here and notice the standard doorway behind
http://www.cloudynights.com/item.php?item_id=1674
you get an idea of how big these sopes are .
The 12" bases in the LB and gso are also big but with the LB at least the
ota breaks down into two pieces .

blue skys advice is great .. have a look at a few scopes before you decide .

cheers and good luck with your choice

rmcpb
09-04-2008, 08:39 AM
Listen to the Nightstalker!!

spikeface
09-04-2008, 06:38 PM
thanks so much everyone! i sense a dob around the corner...

and nightstalker... thanks for the help... you've really cleared up a bunch of things... one more question though... the lightbridge dob... is the finderscope one of those red laser things that meade often uses? my last telescope had a faulty one... and i'm a little bit down on the whole product... and are lightbridges generally the best way to go? i realise i may be asking questions whose answers require personal opinion only...

i'm so freakin excited... i'm going to (humbly) brag my arse off when i get it! thanks again, everyone!;)

edwardsdj
09-04-2008, 07:03 PM
Hi spikeface,

I have the 12" Lightbridge and they do come with one of those red dot finders. Personally, I would have gone a solid tube if it would fit in my car (I drive a Celica coupe).

The Orion 12" Dob with computerised object locator looks considerably smaller to me than an assesmbled 12" Lightbridge and if I was spending the type of money you are talking about and drove a Falcon, I'd be tempted to get a quality product like this.

With the Lightbridge, you pay for the portability. Don't expect a really well engineered package. Some parts of the package are really good, others need work.

Some things I would point out about the 12" Lightbridge:

The shipped 26mm 2" QX eyepiece is next to useless;
The primary mirror springs are too soft and need to be replaced with stiffer springs to hold collimation;
The base is much larger than it needs to be and can't be dissassembled (without modifying it to make assembly and reassembly possible without destroying the base);
The finder is a red dot finder;
There is no cover for the secondary mirror; and
There are no caps for the tube sections.

Aside from all these limitations, the portability of the system has been a boon to me. I found purchasing a proper 8x50 finder and Bob's Knobs primary and secondary collimation knobs and stiffer primary springs to be essential to get the most out of the Lightbridge.

To sum up: if you need portability go the Lightbridge; if not, go a quality solid tube preferably with a computerised object locator.

Hope this helps.

Have fun,
Doug

PCH
09-04-2008, 08:44 PM
Hi Spikeface,

I ahve the 12" LB and would say ditto edwardsdj for all points made, except that I like the red dot finder.

Regarding ep's, I found that a Televue 25mm Plossl was a better choice for me, rather than the supplied 26mm 2" Meade ep which seemed to suffer from what I think is acute coma.

But otherwise a great scope and a real light bucket as they say.

Cheers,:thumbsup:

GrahamL
10-04-2008, 06:47 AM
yeah finders are a personal thing ..I use my telrad most of the time
http://www.backyard-astro.com/equipment/accessories/telrad/telrad.html
I have an 8x50 as well That I use a fair bit but once used to star hopping with the telrad probbably only use it 20% of the time .

rmcpb
10-04-2008, 08:55 AM
Unless you have a van then a solid tube 12" will be too big to transport, and you will want to transport it at some time. 8 & 10" solid tubes are generally no problem to transport.

This is the edge that the Lightbridge series gives but be prepared to modify the mount to make it foldable, its strange that they make a scope that can be folded but leave the base as a HUGE chunk of particleboard.

Exciting, isn't it :)

koputai
10-04-2008, 10:01 AM
Au contraire.
I have the GSO 12 inch and it fits no problems into the back of my liftback 1989 corolla. Of course, I don't think it would fit in a Foul-can or a Commode.

Cheers,
Jason.

programmer
10-04-2008, 10:44 AM
I think this is vaguely related to the thread..:whistle:

Does anyone carry their big-ish dob (say, er, 10" GSO) on the car roof? Is that silly? I'm thinking it would have to be well insulated against vibration and shock, but should be possible... It's about the only way I'll ever take mine away on a trip WITH the family.

Tannehill
10-04-2008, 11:03 AM
only way I'd consider roofing a newt tube is after removing the mirror, which isn't really that big a deal, if you are very keen to take your scope with you on holiday.

....other option: roof the spouse to make room.

Hey, who said that??!!....geesh that's cold, man....

please no one tell my wife....


S

programmer
10-04-2008, 11:47 AM
I guess.. The secondary shouldn't be bothered too much(?) I wish one of those cool aerodynamic roof pods came in a big enough size:D