2" to 1.25" adaptor (ST102)

[davyludo]

Soooooo...... I've just nearly lost my diagonal and eyepiece out of the back of my ST102, after bumping into it 

The ST102 has a 2" fixing in the focuser that uses 2 thumb screws to hold the 2" to 1.25" adaptor (rock solid, I'm happy with this). Then the 1.25" diagonal is held into the adaptor with a single thumb screw (not rock solid, I'm not happy with this). It just doesn't seem the most secure fixing method - and after tonight, I'm even less confident about single thumb screws.

Recently I upgraded diagonal and barlows to ones that have compression rings. Personally I feel these are a lot more secure - so I was wondering if I could change my 2" to 1.25" adaptor for something that is a more secure fit for my diagonal?

I couldn't find something with a compression ring, but found the following item:

https://www.harrisontelescopes.co.uk/acatalog/revelation-self-centering-2-to-1.25-eyepiece-adaptor.html

I just want to know if anyone uses these, and if it would be a suitable replacement for the adaptor in the ST102? Never come across them before, so might be looking at the wrong thing. Any advice would be greatly appreciated.

Cheers,

Davy

[Dave In Vermont]

The 'Twist-Lock' adapter - one of which you posted - are quite good and solid. Baader makes another model.

These have many devotee's, just be careful using any adapter when securing heavy objects into your telescope so as to prevent their working loose and dropping an expensive camera or similar disaster.

Hope this helps -

Dave

[DRT]

I use Baader adapters for exactly the reason you describe. Either of these would do what you are looking for and would be very secure:

https://www.firstlightoptics.com/adapters/baader-2-to-125-reducer-adapter.html

https://www.firstlightoptics.com/adapters/baader-clicklock-2-125-adapter-2956214.html

I can't vouch for the Revelation item you linked to but it is certainly a reputable brand. I always just plump for Baader because I think the extra few quid is worth it.

[PeterCPC]

I use that one and find it very solid.

Peter

[John]

Does your ST102 use this sort of 2" - 1.25" adapter ?:

[rockystar]

yeah, I've got one of those, I some times struggle to get it lose, I'm happy that my EPs are secure with it. Can't remember if it also comes with a thumb screw but there is a hole for one, for added security.

[davyludo]

43 minutes ago, John said:

Does your ST102 use this sort of 2" - 1.25" adapter ?:

Hi John, that looks exactly like the one that I've got just now. 

Are you going to tell me there is a cool gadget that I've not found yet, that I can screw into T-thread? 

[davyludo]

Brilliant,  thanks so far for comments. At least I know I'm looking at the right kind of thing. Quick look last night, I could only find people with reflectors who used the revelation one, so I wasn't 100% sure it was what I was looking for.

I'll need to do some more looking, because I definitely feel like this is something that needs upgrading before a disaster happens!

[Paul73]

These are pretty good and a lot cheaper than the Baader version.

https://www.harrisontelescopes.co.uk/acatalog/revelation-self-centering-2-to-1.25-eyepiece-adaptor.html

Paul

[davyludo]

16 minutes ago, Paul73 said:

These are pretty good and a lot cheaper than the Baader version.

https://www.harrisontelescopes.co.uk/acatalog/revelation-self-centering-2-to-1.25-eyepiece-adaptor.html

Paul

Hi Paul, yeah that's the one I was thinking about trying. I've got a couple of other revelation bits and I'm happy with the quality and price point. Some of these adaptors can get quite expensive!

[John]

43 minutes ago, davyludo said:

Hi John, that looks exactly like the one that I've got just now. 

Are you going to tell me there is a cool gadget that I've not found yet, that I can screw into T-thread? 

What was going to say is that it's worth checking that the bottom part (the flared bit) is actually a 2" fitting. On some Skywatcher focusers the drawtube that the adapter fits in is a bit over 2" in diameter so a normal 2" - 1.25" adapter (ie: the compession ring or twist lock types) might not be a good fit in place of the stock skywatcher adapter. If the drawtube fitting is a 2" then other adapters should work fine.

Also, the stock 2" - 1.25" adapter (the one I pictured) adds quite a bit of length so if it's replaced with a lower profile unit you will need to move the focuser out a bit more to reach focus.

None of these are big deals just the niggling little details that are worth checking

[davyludo]

5 minutes ago, John said:

What was going to say is that it's worth checking that the bottom part (the flared bit) is actually a 2" fitting. On some Skywatcher focusers the drawtube that the adapter fits in is a bit over 2" in diameter so a normal 2" - 1.25" adapter (ie: the compession ring or twist lock types) might not be a good fit in place of the stock skywatcher adapter. If the drawtube fitting is a 2" then other adapters should work fine.

Also, the stock 2" - 1.25" adapter (the one I pictured) adds quite a bit of length so if it's replaced with a lower profile unit you will need to move the focuser out a bit more to reach focus.

None of these are big deals just the niggling little details that are worth checking

Things i never would have though about! I've just bought a 2" diagonal and it seems to fit into the focuser quite snuggly (with adaptor removed obviously). So I'll assume that the drawtube is actually 2". 

Didn't think about the length changing. Will check that there is drawtube distance left, and that I should still be able to get things in focus.

Thanks John 

[davyludo]

Just ordered the revelation one to try. Thanks all 

[DRT]

You might also be interested in one of these for an even better grip on the 2" diagonal and 2" to 1.25" adapter. It replaces the black ring at the end of your focus tube and can be installed in just a few seconds ?

https://www.firstlightoptics.com/adapters/flo-compression-ring-adapter-synta-skywatcher.html