SW 80ED - "Visual Back" / Focusing tube connection

[iwatkins]

Hi All,

Recently purchased a Skywatcher 80ED DS-Pro which I'm very happy with and hope to get first light over the next few nights.

I have been trying various EPs, diagonals, extension tubes etc. and all is pretty much OK.

Where everything attaches to the focus tube, there is a screw on ring with additional locking ring. This main ring allows you to slide in an EP and then lock it in place with with two screws. I believe this part of the telescope is called the "visual back"?

Anyway, if I add an extension tube then my DSLR, even if I tighten the two screws on the visual back, I still get some slop and it moves quite easily.

But where the camera connects to the extension tube, that has a single screw and a brass compression ring. It is easy to tighten and is rock solid.

Anyway, is it possible to buy a single screw with brass compression ring "visual back" to replace the current one on this telescope. If so, I would welcome any recommendations or even advice as to what it is known as so I can search for them.

Thank you in advance.

Cheers

Ian

[Horus]

I have exactly the same same set up , I don't get any movement if you tighten the main ring on the block

[jgs001]

I have the same setup... lock the two rings together, then give both locking screws a small (about 1/4 turn maybe, that's what I used) turn with a pair of pliers.. Do the same with the screw for the brass compression ring... I found I could not get them tight enough by hand to remove all movement (albeit ever so slight, I couldn't tell)

[Horus]

Spot on John , I meant to add " lock the two rings together "

[ollypenrice]

I use pliers too, when I have to, but easy does it! You can shear off the lockscrew and that IS a pain. Can't you screw the camera adapter straight onto the back of the drawtube with SkyWatcher? I don't have one here but thought you could?

Olly

[jgs001]

That's why I said a small amount more or less... I don't have the SW version, but the Celestron version. The screw thread is designed and works perfectly with the focal reducer, and the camera screws onto that with a T ring... that's probably the best option, but it's a lot more expensive option.

I know what you mean about sheared locking screws, my original diagonal had one... no idea how, but it was never abused..

[iwatkins]

Thanks guys.

I've tried all combinations but I simply cannot get a solid connection with the camera attached. Problem lies where the extension tube attaches to the focus tube. I'm going to try another extension tube.

Certainly won't be doing it all up with pliers, already have marked my current extension tube quite badly.

Cheers

Ian