Dobsonian telescope,what can i see?

[TheAstroChannel (Sean)]

Hey guys, im considering buying an 8" Dobsonian and i have a few questions.

What can i see through an 8"?
Will i be able to take long exposures?

-Sean

[vaztr (Andrew)]

Sean,

The first answer is LOTS - I had an 8" dob for three years and can honestly say I never got close to seeing 'everything' that it could display.

No, the Dob isn't a scope for astrophotography at all, you really need a guided scope and I'm sure some of the photo boys and girls can let you know what is needed

VAZ

[mental4astro (Alexander)]

Like Vaz says, an 8" dob is a great instrument, take can provide a lifetime of viewing. It is a great planetary instrument, an terrific with the Moon. It is capable of resolving hundreds of globular clusters & show fantastic detail in nebulae & galaxies.

It can be used to take photos actually, but this is limited to the Moon & planets as these are bright. There is also free software that is used to stack the many frames of video that is taken, & the software is powerful enough to do all the aligning & processing that's needed for fine images to be produced. For fainter objects an equatorial mount that tracks is needed

There's an article project about photography with a dob in the articles heading in the left margin. Have a look.

Mental

[TheAstroChannel (Sean)]

Thanks a lot guys, but i really want a telescope that's good for Astrohphotography that isn't going to cost me thousands.

I first originally wanted this telescope ( http://telescope.com.au/Telescope/Ho...%2cProductName )

But then a few people told me to consider a dobsonian.
But from what i have heard and seen, the Dobsonian isn't a good telescope for imaging the night sky. I dont know :S

[mental4astro (Alexander)]

Sean, the scope you linked to is only as good as a dobsonian for photography. Yes, while it tracks, it isn't aligned with Earth's axis and the result is rotation of the image. For good astrophotography you need an equatorial mount. Good mounts are important for stability & reliability. Especially if you want to do more than take wide field shots.

Other more qualified people can make gear suggestions gear wise for photography. The furtherest I take it if basic video imaging with my old but trusty Celestron C8, but it too is equatorially mounted. No processing, just live viewing on a tv screen. But it's enough to show me a colour image of Eta Carina & Orion nebulae from home in Sydney.

Mental.

[Forgey (Paula)]

Sean,

If you want to do long exposure astrophotography it isnt going to be cheap im sorry to say.
Mount/telescope/camera/guidescope etc you'll be looking at $1000 minimum.
Do some reading and research before you jump into it. It's not as simple as buying a telescope putting it on the ground and off you go. There is lots more to it.

I really think you need to visit an astro society or even drop into BINTEL http://www.bintel.com.au/ and get a feel for some telescopes and look through them, see what they actually look like.
A list of clubs/societys In VIC can be found here http://www.iceinspace.com.au/clublistings.html#VIC

[TheAstroChannel (Sean)]

I guess i might just consider i nice reflector until i get a job( Hopefully after christmas ) so i can afford to buy my own Dobsonian!

[alistairsam]

Hi Sean
The Dobsonian that you're referring to is only a type of mount, that is alt azimuth
Whilst there are tracking dob mounts like the skywatchers, they will cause images in the eyepiece to rotate.
For photography, you need an equatorial mount that has goto capabilities and supports an auto guider input for auto guiding, without which long exposures are very difficult
As for what goes on the mount, it could be a reflector or a refractor
The ed80 is a very good refractor that keeps your weight low, so you could go with a mount like the heq5 pro
If you go with a reflector any more than 8inches mirror dia, you'll need a sturdier mount with a higher payload like the eq6
It all starts adding up
I'd suggest reading throug some of the threads here with equipment recommendations and that'll give you a good idea of what's involved
It also depends on your budget. What are you looking at spending?
Again, the Dobsonian is an alt az mount, mostly used for visual observation