Astrophotography setup

Hey.

I know this has been covered to death already, but I need some help in choosing a setup for astro-imaging.

I am planning on using my dslr (350d) and regularly use it as a piggyback on some club scopes.
However, I really want to start doing this properly, ie. My own mount, scope and tracking.

I was going to buy a large (8-10") dobsonian, but have thought about it alot and know that I need an EQ mount to get good images as high powers - through the scope itself.

Can someone help me to pick something that I will enjoy.

My budget is roughly £400.

I would ideally want it to be small enough for me to carry by myself and load into the car.

On another point, I am familiar with programs such as registack and would like to know what is the longest exposure I can use at 50mm before I get star streaks? Also, as the camera at the moment is on a normal camera mount which I don't want to rotate during shots, would it be possible for registack to take 100 or more images and stack them even if they have rotated somewhat due to te time difference between each shot?

Thanks a million.

Jay

Hi Jay, Here's my 2 cents worth..

I was going to buy a large (8-10") dobsonian, but have thought about it alot and know that I need an EQ mount to get good images as high powers - through the scope itself.

A dob since they are usually large would require a large mount, maybe the balance would be affected by a camera on top? I think a reflector would be better because of it's physical size if you want to shoot straight through the scope, for piggyback shots, a small motorised mount is all you really need with a scope on top, big or small, just take into account how easy it would be to polar align, as this would be critical. You're definitley not going to get a dob into a car

On another point, I am familiar with programs such as registack and would like to know what is the longest exposure I can use at 50mm before I get star streaks? Also, as the camera at the moment is on a normal camera mount which I don't want to rotate during shots, would it be possible for registack to take 100 or more images and stack them even if they have rotated somewhat due to te time difference between each shot?

Registax is good alright for stacking , but not good for rotating shots of the sky as I have found. Better to try Deepsky Stacker here: it's a greta program and handles rotated shots well
deepskystacker.free.fr/english/index.html

As for the 50mm, I've gotten 10 minute shots before with a good motorised well polar aligned mount, but if the 50mm lens is on a tripos, then at best 20 seconds I find until the streaks appear.

Hope this helps...
Keith..