SKYWATCHER SKYLINER-400P FLEXTUBE SYNSCAN GO-TO

If I were in the market for a 16" goto dob right now, my choice would be the Orion XX16g. Same synscan goto system, Same Synta optics. Same conical Primary mirror. Same dismantelable rocker-box.

The main difference is in the truss/strut system and the knock-on effects those design choices had on the rest of the scope.

A 3 pair or 4 pair truss system is very rigid. The trusses can be really long. That means a shorter Lower OTA and rockerbox. A parallel 3 or 4 strut system is not as rigid. To maintain enough rigidity so that collimation holds you can either make the struts thicker or you can make them shorter. Skywatcher went for shorter for this reason and also because longer poles would bottom out on the groundboard when the scope was collapsed before the UTA got close to the Lower OTA. Not much point in a collapsible dob if the OTA doesn't collapse all the way like the rest of the flextube line This means the lower OTA is taller and thus the rockerbox is taller too. Skywatcher went for 3 struts for their collapsible flextube system. It works fine on the smaller apetures where they can get away with longer struts because the scopes are lighter and longer relative strut lengths are still rigid enough. However the design doesn't scale up well but they did it anyway because if they didn't it wouldn't be a member of the flextube line. Hence you end up with a massively oversized Lower OTA and rockerbox. (As if these chinese dobs weren't massively oversized enough compared to the ATM designs)

Because Orion continued their use of 4 truss pairs from the rest of their XX line, they have much long trusses, thus shorter Lower OTA and thus shorter Rockerbox. Look at the height of the top rim of the Lower OTA in both vids. Both lads are 6 footers. The skywatcher Lower OTA is abover yer mans waist and the Orions is only half way up yer mans thigh.

I'd say the Orion will be easier to handle, hold collimation better because it uses trusses instead of struts and you won't have to get a fancy shroud with stiffening rings to hole the shroud out of the lightpath on the Orion whereas you would for the skywatcher.

Keith, they only downside i can see to the xx16, is i cant find somewhere in europe thats selling it

Hi Calibos
Thanks for that, looks like a very well designed and portable Dob.
Worth consideration!

Lovely looking scope, didn't realise they came in GoTo. SCSASTRO in Somerset sell them but they don't deliver outside the UK.... did I hear someone say "RoadTrip". : cheer: Oh and they aint cheap 3000 sterling... fine looking scope though.

Telescopehouse and Widescreen Centre both in London sell Orion Telescopes, just sent them an e-mail!

3000 sterling! wow thats pushing it