non-compresso

[Moonshane]

hi all

I have a Celestron 120 OMNI refractor which I think is great but I am looking to buy a new 2 inch diagonal and don't want to mash the tube on the new toy with the thumbscrews on the drawtube of the scope.

I have bought a 2" 'extension tube' with compression connection but fear that when I get a 2" diagonal, the eyepieces will be too far out to 'near' focus (I currently use 1.25" kit). This will be even worse with the barlow.

Has anyone seen a shorter 'extension tube' which just effectively converts thumbscrews to compression? If not, anyone fancy making one as I bet they'd be popular!? I could possibly get a mate to turn away the 'excess' extension so the extender will slide into the drawtube more I suppose but if I can get a ready made solution this would be better I reckon. Ultimately I suppose I could always get a new crayford with compression fittings but I'm not ready for that yet (moneywise).

Cheers for any help

Shane

[skye at night]

maybe?

Adaptors - Moonlite 1.5" Focus Extension Tube

[John]

Don't forget that when you use a 2" diagonal you use up a fair bit of focus travel because of the longer light path through the diagonal. You will therefore need a low-profile compression ring adaptor which is usually referred to as a visual back rather than an exension tube. Mercury Systems used to do them for Synta scopes (the Omni 120 is made by Synta) but I don't think they are available any more.

In the end I've just had to accept some marking on the barrel of my diagonals.

[Moonshane]

cheers both of you

John in partic. put me onto this

Moonfish Group® Store

had never considered visual backs.

the hunt is on for a used one now!