Brand v Brand

[Sconesbie (Scott)]

Yet again, this topic has probably been done to death over the years.

Hopefully at the latter part of this year I can afford a new scope. I have narrowed it down to an 8" or 10" goto Dobsonian (pending the treasurers report once the books have been done).

I had the final decision narrowed to a Skywatcher flex, then I found the Orion Skyquest full tube which is cheaper. I can virtually get a 10" full tube at roughly the same price as an 8" flex (just from rough guides online). I haven't done in depth price research at this stage on the Orion.

Goto is certainly what I want but need to get an understanding if there is really any difference betyween truss and full tube. It's highly unlikely I will be transporting it anywhere and won't be doing photography. Just gazing.

Thoughts please ladies and gents.

[AG Hybrid (Adrian)]

If you don't have any trouble transporting and moving it about. Go with the solid tube. The Orion and Skywatcher telescopes are both Synta built. Including the optics. The Skywatcher collapsible truss mechanisms are more difficult to construct then a plain solid tube. Your paying a bit extra for more convenience you said you wont be needing.

[-George-]

Solid tube is more stable. You can also manage thermals better in a solid tube, thus more preferred for planetary viewing. I have a 12" solid tube, I still have to lean over to view... feel like I could have bigger.

[raymo]

I have to disagree with George. The blanket statement that a solid tube
is more stable does not always apply. My 10" Flex Dob is rock solid, and
requires no more frequent attention[including collimation] than my old 10" solid tube did. As for tube currents, my FD primary mirror
equalises quicker, and tube currents are comparable with the solid tube
scope. In case anyone is wondering why I would swap one 10" for
another; the old mirror needs recoating, and the FD fits into my hatchback more easily, and because I am getting on in years, anything
larger is just too heavy.
raymo

[barx1963 (Malcolm)]

Originally Posted by -George-

Solid tube is more stable. You can also manage thermals better in a solid tube, thus more preferred for planetary viewing. I have a 12" solid tube, I still have to lean over to view... feel like I could have bigger.

I am with Raymo on this. My last 3 scopes have been a solid tube 12" GSO, a 20" truss dob and an 8" homemade travel scope. Of these the one that needed the most tweaking on setup was the 12". Several times with the 20" I have put it together and it is spot on! I do however always use the tubes in the same order and assemble in the same sequence so reducing any risk of error.
As for tube currents, logically a solid tube is going to be affected more by these and the solid tube will also slow down mirror cooling.

Malcolm

[AG Hybrid (Adrian)]

Originally Posted by -George-

Solid tube is more stable. You can also manage thermals better in a solid tube, thus more preferred for planetary viewing. I have a 12" solid tube, I still have to lean over to view... feel like I could have bigger.

Who told you that?