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Baader SCT to T2 adapter.

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#1 Eddgie

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Posted 16 March 2013 - 11:53 AM

Does anyone have one of these?

From the picture, it appears that with this in place, to rotate the diagonal, one would have to loosen the collar that holds the adapter in place to rotate the diagonal.

Is this correct?

If so, how secure do you think this is. It would seem to me that when the binoviewer was tilted to the left of the centerline, the tendency would be for the collar to slip.

This was an issue with the old SCT diagonals when used with heavey eyepieces. By the time you got it tight enough to prevent torque from twisting, it became difficult to back it off to rotate the diagonal.

So, anyone that has some experiecne with this, I would appreciate letting me know how it works.

Thanks!

#2 Tamiji Homma

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Posted 16 March 2013 - 12:39 PM

From the picture, it appears that with this in place, to rotate the diagonal, one would have to loosen the collar that holds the adapter in place to rotate the diagonal.

Is this correct?


Are you referring to this one?
Posted Image

If so, that is correct. You can rotate diagonal before you tighten the collar (larger ring).

Tammy

#3 Eddgie

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Posted 16 March 2013 - 02:32 PM

Well, it is like this, but I don't know if it is this exact one.

One side is T2, the other is SCT thread. In the picture, it looks like this, but I don't know if your focuser tube has SCT threads.

But As I understand it, is it the little knurled ring that goes up against the face of the diagonal body?

So, can you loosen that, rotate the diagonal, and then tighten it?

And will this allow enough grip to keep it from rotating to the side if I have the binoviewer at an angle?

Sorry, it is not obvious from the picture.

Also, in the picture, there appears to be a little set screw hole in the ring just in front of the diagonal face.

Is this to secure it into position against the forementioned possibility of rotation?

Thanks!

#4 Eddgie

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Posted 16 March 2013 - 02:35 PM

Ah, Ok, you mean the thick ring at where the big knurled ring attaches to the focuser.

If that is the case then it is like an SCT diagonal where a flange on the nose inside the front ring is simply clamped so it has friction to prevent rotation.

I never liked that arrangement on SCT diagonals, though I suppose if they left a generous flange so you have ample clamping power, I suppose that would be OK.

I use Hyperions though, and they are so heavy that I worry about rotation.

#5 Crow Haven

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Posted 16 March 2013 - 03:29 PM

I really wish manufacturers would stop making these pieces for the sct to t-2 adapters out of highly polished anodized metal -- it just makes the parts too slick, and when you tighten down the large sct ring it's still able to rotate enough that it's not secure for heavy accessories...and if you tighten it down too much you can hardly even remove it. At least that's what I've found, the Baader adapter must be better. This weekend I took apart an old Celestron refractor/comet catcher t-adapter (part#93634A) which was just the sct ring/t-2 removable parts on one side and another removable threaded ring part on the back, but it was not shiny slippery metal, it was the old matte-black textured finish inside and out (which also I prefer on the interior threads since these then don't shine and reflect). I took the sct/t-2 part off my 2" sct diagonal and replaced it with the old textured flat black sct/t-2 assembly and it tightens down way better and stays put at last! :grin:
---Maya

#6 Space Dragon

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Posted 16 March 2013 - 05:40 PM

Eddgie
I have this adaptor and while it is very short, maybe less than 10mm, I wouldn't be happy hanging a load off to the left.
I use it alt/az with a CPC so it just stays put.
I wouldn't like to alter the position with a load on it either, it's ok when it's just the diagonal.
It would be very secure off to the right however.
To be clear it's this one in the link:
http://www.teleskop-...ader-Adapter...

#7 HTJ

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Posted 16 March 2013 - 05:48 PM

I have the adaptor. I pretty much agree with what Space Dragon said.

I would not hang something heavy on them on a GEM mounted scope. I cannot tighten it enough to make the T2 part steady enough.

It might be possible to modify it, e.i., gluing the entire thing or putting rubber on the T2 inner side somehow.

#8 Eddgie

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Posted 16 March 2013 - 05:56 PM

Yes, this is my concern. It will be fine on one side, but prone to slipping on the other.

I have already ordered it though.

Maybe cutting a ring of some kind of rubber gasket material and cementing it to the inside of the flange would help.

I don't know why I am fussing with it. I don't use the EdgeHD 8" hardly at all. I guess it is just that when I do, I want it to work as well as possible.

I can mount the C5 Alt/Az so that will be OK I think.

Another option may be to take a rasp, lay it across the flat face of the adapter and use a hammmer to dimple it to give it a bit of texture. Might have to do it to the flat at the rear of the SCT port to.

This was the reason I avoided it to begin with, but I am determined to get most of my aperture back. Shortening the focal lenght 60mm won't hurt either.

Of course it might work fine. Just have to be sure to reallly lock eyepeices in tight in the event that it decides to rotate.






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