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View Full Version here: : 12” dobsonian GSO or SW collapsible “HELP”


Davekyn
25-09-2008, 05:51 PM
Before taking the plunge into astrophotography & all its expensive accessories, I have decided to buy a 12” Dobson to learn more about the night sky. I will be ready to order within the next two weeks and can’t decide among the following two Dob’s. (Andrews Communication)
Guan Sheng GS-980 12" ASDX 300mm x 1500mm
VS
SKYWATCHER Collapsible Dob 300X1500mm

Dobson Measurements???
Could any 12inch Dobson owners please tell me the Length & Width of their OTA’s (THE TUBE)& list the type of Dobson owned….Thanks!
I own a “Hyundai hatch back” and have measured that I can fit a tube length of up to 160cm with a width of up to 45cm with hatch closed…I can push the length to 170cm but without passenger.

Despite the option of Portability which is the Better Dob…What are the pros & cons between when sizing up these two dobs (OTHER than portability)

The Skywatcher looks tempting but if I can fit the GSO in my car, I may tend towards using the GSO due to the benefits’ of having more of the components better protected from the elements.

If using some kind of “light Shroud” how would you attach it to the collapsible Dob??? The truss design does not seem to really cater for a shroud (only three tubes making for a triangular shape?)

What eye pieces are better to use…the 2inch ones or the 1.25inch???

Accessories:
With the GSO Dob you get:
Super Deluxe version includes a right-angle correct image 8 x 50 finderscope, 2" Crayford style microfocuser with 10:1 fine focusing and a 2" to 1.25" adaptor, fan, GSO 6mm, 9mm, 15mm and 25mm 1.25" Plossl eyepieces - and a bonus SP32mm 2" eyepiece, too![/font]
That's five high quality eyepieces included (not just two or three)!!

The Skywatcher Collapsible does not Advertise and Extras!

What accessories would I consider to make my using these dobs more effective?
Is it worth investing in filters???
What about “Barlows??”
I would also like to use from my light infested residence if possible.

That’s about it for now…
And info is always good…Cheers,
Dave

erick
25-09-2008, 10:01 PM
147cm long, 37cm in diameter. But that diameter doesn't include the focusser, side bearings and finderscope (if you left it in place). Mine is a Bintel GSO which was new early in 2007. I expect it will be pretty close in size to the one Andrews is selling.

Dave, I'd be more worried about the base - they are quite big. I haven't measured the one I have but can do so in the next few days if you want. Alternatively, feel free to try and estimate it from the attached :)

norm
25-09-2008, 10:16 PM
Hi Dave,

Have you also thought about the 12" Meade Lightbridge or the Orion
Intelliscope ?

http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=09793

I haven't seen the latter, but looks pretty good.

As for the shroud, you could knock one up by sewing a plastic or wire band at the centre to stop it from straying into the light path. Checkout Astrozap's website, they may have one now for the Skywatcher. Alternatively if u go the Meade path, PM me I have one available;).

Cheers,
Norm

rmcpb
26-09-2008, 08:35 AM
If I owned a Hyundi I would be looking at one of the collapsible 12"ers. Even with the OTA collapsed the base is huge but a bit of inventiveness with some piano hinge and spring catches should enable it to store flat in the bottom of your car.

As for accessories, you only need a few to get started. A stool, a red torch, a planisphere and a cheshire eyepiece for collimating. All the other bits n pieces will come in their own time but make sure you have had a lot of time with the scope before getting into the accessory market.

erick
26-09-2008, 09:21 AM
I measured the base of my GSO 12". Around 63cm in daimeter and 66cm high.

Davekyn
26-09-2008, 11:45 AM
Thanks guys,
It would seem from the measurements I have obtained here and elsewhere, that I could indeed fit the 12” GSO Dob in my car “JUST” (Oh yea…good point on the “Finder” ThanksJ)

Anyways…My research shows thus far…That I may be able to minimize the contaminants (when using the Truss design), by using a can of compressed air to remove unwanted dust from a distance of around 1 foot from the mirror.

I have also considered using VELCRO and ultra light weight Tent Poles to help assist a home made shroud.

Thanks also for the recommendations on the other dobs…I will check out the Light Bridge reviews later, however the inteli scope will be too much for current budget. I was thinking the Skwatcher might have ironed out a few kinks the light bridge had seeing as it seems to be a much newer release.

The Truss Dobs certainly make for a good travel scope…I’m still wondering…now that I know I can fit a GSO in my car…what the major difference are going to be between using a fully enclosed tube compared to a truss? Because if it’s only minimal and I have maintain my mirror more often, then I guess that is not so bad… Doh… Never in my life have I had so much difficulty when buying such things…I’d rather be choosing a mother board or graphics card J

Thanks again…let me know if I should be thinking of something else here…I’m thinking I might damage the GSO TUBE & mount, with all the dismantling I will be doing to fit in my car with all the trips I will be doing.

I guess the Truss will do…After all…this DOB is just so I can learn the night sky and get started now…I will be more pedantic about my imaging equipment…if & when I acquire it.

erick
26-09-2008, 11:57 AM
I've only been around about two years, but starting with a 12" just to learn the night sky - whoda thunk it! Go for it, Dave! :)

Paddy
26-09-2008, 01:18 PM
I have a 12" GSO and find it cumbersome to get into my Camry wagon. The OTA is OK but the base can be a pain. Bear in mind that you have to get it into the car, so internal measurments are not the only consideration. We have the car on gas so there is a tyre in the back which prevents loading the base through the back so it goes through a door, just. If you plan to move your scope a lot, I would suggest that go for something more portable. Having said all of that, I am very happy with my GSO dob, but I rarely put it in the car

Have a look at July's sky at night - they had reviews of various 12" dobs and had the Meade 12" lightbridge as front runner.

rmcpb
26-09-2008, 01:45 PM
Another possibility is that a smaller scope may do the job for you and allow extra mobility in the small car. If you are going to progress to astrophotography quite quickly and the dob is just to learn the sky why not think about an 8". You can certainly learn the sky with one, I have yet to run out of objects to hunt down after quite a few years, it is easily transportable in a Pulsar hatchback and remember the best scope is the one you use the most.