The Dilemma of what Dob...

[JohnnyBGood]

(My first post on this forum so treat me gently)

Am about to upgrade from my current Nexstar 6SE (decided it was a good compromise scope when I bought it a few years ago).

Now, after much pondering have decided to buy another scope, this time a dobsonian (my first dobo!).

Have read these forums but still to do a bit more research to do (Neil English book "Choosing a Dobsonian telescope" on it's way from ebay).

8", 10", 12" (or larger!)?, Manual, Auto or GOTO?, Solid or Flex?, White, Black or Polka dot?

All sorts of variables to ponder.

Decisions, Decisions....

Having fun just reading up on the subject.

Watch this space.

[ItIsOnlyMe]

Welcome !!

I have a 300p Flex Auto and have added goto, I get little value from the goto as much of the joy of a dob is the instant push and find without the need to set the thing up first, Auto is genuinely useful, go and make a cup of tea...come back and it's still pointing (roughly) where you left it.

Flex is useful for storage and transport on a back seat/boot e.t.c (sits behind the sofa without being too obvious) and isn't too bad for collimation which is close on but worthwhile each serious use.

Bigger IS better but think about your circumstances first e.g. does it need to go in the car, how heavy is it e.t.c.

DON'T BUY A BIG DOB UNTIL YOU HAVE SEEN IT..and thought about transport, moving to the garden..storage e.t.c.

If you can get one go with Polka dot :-)

[John]

A recent survey on here indicated that, of those that responded, a 10" dob was considered by many the optimum size in terms of portability balanced with viewing capability. 12" or more is even better for viewing of course but these are quite large beasts. I viewed though a 20" dob once and that seemed about as big as a small car !. The views were to die for though !.

If you can keep the scope in a roll-off roof shed or similar or just roll it out of a garage (you can fit handles and wheels for this) then go for as much aperture as you can.

It is worth looking at some of these scopes before taking the plunge though, as ItIsOnlyMe suggests.

[swamp thing]

Hi

Before you reach a decision, think about where you will keep it and what transport arrangements you may require, if any.

The principle advantages of the Dob are it's cost per aperture and it's ability to transport to dark skies.

This last reason for me is the deal clincher. Any scope at dark skies will run rings round a much larger one badly placed in a LP position.

If you have a dark country sky at home this is of no concern, but if your sky is suburban the ability to take the scope on dark sky forays is a real advantage.

Pick the scope that you are able to transport.

A good analogy I think is this: it's OK to substitute aperture for dark skies but never sacrifice dark skies for a larger aperture.

Regards Steve

[ismangil]

Hi Johnny,

Welcome from fellow Sheffielder!

If you don't know already, there's Stargazing event from Sheffield Astronomical society on 10 Dec (SAS | Sheffield Astronomical Society | details of our latest meetings and events)

Usually there's at least one or two Dobs there, so you can get a feel for the size.

You need to get the 'right size' for your circumstances... Transportability and handling is important.

[JohnnyBGood]

Thanks for all your replies to date.

Had thought of popping over to Mayfield on the 10th but am engaged on thge day (driving a friends kids, complete with pet snake!, down to London).

Think I have a handle on the variations aound the size and type of scopes. Don't really consider the larger dobs as portable (not with my back), more "transportable". Furthest I'm planning on travelling for the moment is in and out of the shed/observatory. ;-)

Not really a stranger to astronomy.

Have dabbled since I was a nipper. I can even remember trying to find Apollo 8 orbiting the moon with my dire (but loved) 50mm Tasco back in 68. More recently I was "assisting" a friend with his AAVSO research under the dark skies of Arizona (Braeside Observatory: Telescope).

The thrust of my post is probably not so much the mechanics of choosing this or that instrument but deciding what kind of astronomer I have become and will evolve into...

Or is that too deep? (evil grin!)

PS Have also thought of trading in my current faithful 6SE which might give me a few more options/cash to play with (maybe go for an in-situ 14"?). What might be the sort of part exchange deal I might expect for a good condition 6SE? (with JMI case and numerous accessories). Had thought about driving down to the likes of Astro Engineering to "do a deal" (and a recce for next upgrade in 4-5 years time?)

[JoLo]

I moved from a 10" solid tube Dob to a 12" truss Dob....great choice on my part, if I may be so bold. I find the 12" easier to move around and transport...the 10" tube was lighter, but bulky to move in and out of cars, etc. For my part, I would not go beyond a 12", don't want to deal with the weight, can't afford an ultralight......

Don't have GoTo or tracking experience with a Dob, but after imaging with Atlas / 4" refractor I do like to return to the simplicity of visual with a big ol fat Dob. I'm a fan of star-hopping with the Dob, so, for me, consideration of GoTo or tracking platforms never entered my mind.

[Gina]

I had never even considered a Dob until I was using my 5" Newt on it's mount without power and just nudging it to follow what I was looking at. Then it came to me That's just what you do with a Dob! LOL