Skywatcher Twist Lock Adaptor 2" - 1.25"

[MattJenko]

One thing that was not particularly streamlined in my observing sessions was the swap between 2'' and 1.25'' EPs. I also have a 2'' filter which could only be used by some of my EPs. I wasn't sure whether to buy 2'' or 1.25'' or both in future. Along comes this little beauty I got from RotherValleyOptics.

This item is a 2'' to 1.25'' EP adaptor with a twist locking clamp, which allows an EP to be held without screws by simply twisting the nicely sized grip around the tube end. It is also threaded on the 2'' side for filters, so you can use your 2'' filters with your 1.25'' EPs.

The item arrived a few days late due to me missing the next day delivery, no problems there. The item is a nice weight, compact and simply works. The twisting upper ring clasps the 1.25'' EPs nice and tight and in a non scratching/marking way, which is lovely. It also holds them in a much more central and aligned way than the previous screws and I found that it holds a DSLR with no concerns about slipping and it holds it in a nice straight optical path.

The 2'' filter is held very closely for my TV Radian 10mm. The OIII one I have is probably a single mm away from the filter when all snug in, but it all fits. Some eyepieces with long tubes might well hit the filter, which is something I will need to consider going forwards.

How exactly does this streamline my observing you might ask? The answer is that my previous 2-1.25 adaptor has a small 2'' lip and then a longish 1.25 tube. It added 4 more screws to the whole shebang which in the dark complicates things and also it doesn't fit into the EP holders on any of my scopes, so I cannot swap it out with a 2'' EP without either putting it on the floor, or having to take the 1.25 EP out and/or put both away. Sounds like not a big deal, but after a few iterations, the small frustrations build. This simple item has remedied that for me and given me a whole host of other small features which have enhanced my astro experience. All for about 30 quid.

Matt

[Vox45]

I'va added this to my shopping list Thanks for the review

[Vox45]

This item is a 2'' to 1.25'' EP adaptor with a twist locking clamp, which allows an EP to be held without screws by simply twisting the nicely sized grip around the tube end. It is also threaded on the 2'' side for filters, so you can use your 2'' filters with your 1.25'' EPs.

Do you know if we can screw the 2" thread side to a T mount adapter on a DSLR ? I guess this should work but it is not mentionned in the description... The Antares does mention it so I would expect that it is the same for the SW..

[MattJenko]

Yes it does. You unscrew the 1.25" end and once the internal compression ring is removed, you have a nice male T-thread there. Thanks for asking as I never knew

[Vox45]

he he that is so cool ! One less part to worry about as I needed a 2" to 1.25" AND a T-ring + 2" nosepiece

Thanks for looking into this

I was looking at the Baader T-ring with filter but it comes with a 2" nosepiece, I would like to get only the T-ring part with an integrated filter. I have yet to find such a thing

[Xplode]

he he that is so cool ! One less part to worry about as I needed a 2" to 1.25" AND a T-ring + 2" nosepiece

Thanks for looking into this

I was looking at the Baader T-ring with filter but it comes with a 2" nosepiece, I would like to get only the T-ring part with an integrated filter. I have yet to find such a thing

You should note that the Twist lock adapter isn't suitable for use with a DSLR, it creates heavy vignetting because of the narrow 1.25" which is smaller than the diagonal of the sensor.

For the lowest chance of vignetting you want to use a M48 adapter which the Baader protective ring will give you. It also fits the focal reducer for you ED80 perfectly.

[spaceboy]

I'm not a big fan of these twist lock adapters at all ! and it appears that is the way it is going to be in the future as I see most of the thumbscrew brass ring adapters are now being phased out.

The most notable issue I have came across is that the adapter can twist in the focuser so you think your tightening it but in fact all it is doing is spinning in the draw tube.

There is also a concern in the back of my mind that when you use heavy eyepieces you want to ensure the eyepiece is well secured in the adapter so give it a nice snug twist to ensure you eyepiece doesn't slip out but when you do this you are not just twisting the retaining ring on the adapter but also the focuser drawtube is going to feel some of the twisting which in turn may in the case of crayfords put some strain on the thin focuser rod which sits up against the draw tube. If you lay off the heavy handed twisting you then risk the eyepiece coming loose as the night gets colder. It appears that this may well be an issue as I see the twist lock adapter are threaded for a back up thumbscrew. This will mar the eyepiece if used though.

The brass ring adapters are not perfect by any means but with heavy eyepieces I use 2 thumbscrews and the brass ring means there is no marring going to occur to the eyepiece and the surface contact is increased. I know it is held secure in the adapter and all I had to do is quickly turn a thumbscrew that creates no lateral tugging on the focuser at all. If anything good has come from the twist lock adapters it is that they have put me off swapping out eyepieces / magnification as I just don't feel confident using them and would no way use one on my EQ mount where the focuser can end up south facing.

[Vox45]

You should note that the Twist lock adapter isn't suitable for use with a DSLR, it creates heavy vignetting because of the narrow 1.25" which is smaller than the diagonal of the sensor.

For the lowest chance of vignetting you want to use a M48 adapter which the Baader protective ring will give you. It also fits the focal reducer for you ED80 perfectly.

Correct ... the adapter is for my webcam's 1.25" adapter and a couple of EP's someone lent me until I buy 2" EPs

Now I thought that once you remove the compression ring you get a 2" T thread adapter that can be screwed in a 2" T-ring ? isn't that the case ?

[Vox45]

I'm not a big fan of these twist lock adapters at all ! and it appears that is the way it is going to be in the future as I see most of the thumbscrew brass ring adapters are now being phased out.

The most notable issue I have came across is that the adapter can twist in the focuser so you think your tightening it but in fact all it is doing is spinning in the draw tube.

There is also a concern in the back of my mind that when you use heavy eyepieces you want to ensure the eyepiece is well secured in the adapter so give it a nice snug twist to ensure you eyepiece doesn't slip out but when you do this you are not just twisting the retaining ring on the adapter but also the focuser drawtube is going to feel some of the twisting which in turn may in the case of crayfords put some strain on the thin focuser rod which sits up against the draw tube. If you lay off the heavy handed twisting you then risk the eyepiece coming loose as the night gets colder. It appears that this may well be an issue as I see the twist lock adapter are threaded for a back up thumbscrew. This will mar the eyepiece if used though.

The brass ring adapters are not perfect by any means but with heavy eyepieces I use 2 thumbscrews and the brass ring means there is no marring going to occur to the eyepiece and the surface contact is increased. I know it is held secure in the adapter and all I had to do is quickly turn a thumbscrew that creates no lateral tugging on the focuser at all. If anything good has come from the twist lock adapters it is that they have put me off swapping out eyepieces / magnification as I just don't feel confident using them and would no way use one on my EQ mount where the focuser can end up south facing.

Good point, I'll try to remember that ! Would not want to see my DSLR or 2" EP's fall in the middle of a muddy field.

[Vox45]

 It also fits the focal reducer for you ED80 perfectly.

Ha! that was my next puzzle to solve: "What adapter will I need to buy once I get the FR"

Thanks for bringing that up. Then I don't feel bad buying the Baader Protective ring AND the click lock as they will both serve their purpose

[Vox45]

I'm not a big fan of these twist lock adapters at all ! and it appears that is the way it is going to be in the future as I see most of the thumbscrew brass ring adapters are now being phased out.

The most notable issue I have came across is that the adapter can twist in the focuser so you think your tightening it but in fact all it is doing is spinning in the draw tube.

There is also a concern in the back of my mind that when you use heavy eyepieces you want to ensure the eyepiece is well secured in the adapter so give it a nice snug twist to ensure you eyepiece doesn't slip out but when you do this you are not just twisting the retaining ring on the adapter but also the focuser drawtube is going to feel some of the twisting which in turn may in the case of crayfords put some strain on the thin focuser rod which sits up against the draw tube. If you lay off the heavy handed twisting you then risk the eyepiece coming loose as the night gets colder. It appears that this may well be an issue as I see the twist lock adapter are threaded for a back up thumbscrew. This will mar the eyepiece if used though.

The brass ring adapters are not perfect by any means but with heavy eyepieces I use 2 thumbscrews and the brass ring means there is no marring going to occur to the eyepiece and the surface contact is increased. I know it is held secure in the adapter and all I had to do is quickly turn a thumbscrew that creates no lateral tugging on the focuser at all. If anything good has come from the twist lock adapters it is that they have put me off swapping out eyepieces / magnification as I just don't feel confident using them and would no way use one on my EQ mount where the focuser can end up south facing.

You should note that the Twist lock adapter isn't suitable for use with a DSLR, it creates heavy vignetting because of the narrow 1.25" which is smaller than the diagonal of the sensor.

For the lowest chance of vignetting you want to use a M48 adapter which the Baader protective ring will give you. It also fits the focal reducer for you ED80 perfectly.

In the end I bought a diagonal that comes with a 2" to 1.25" brass compression ring adapter for the EP's

I will get the 2" Baader protective ring for the DSLR and use it in the diagonal without the 1.25" adpater or directly in the 2" focuser as I have a 2" Baader clicklock on it.

Rock solid