40 replies to this topic

[denis0007dl]

Should work, but best to check thread size you have on SCT!

[RAKing]

With Baader parts, you can usually connect anything to anything else.  

 

Baader Conversion ring - M68-2 2458232 will convert 68mm threads on the Ultra-Thin visual back to SCT threads.  it's in stock at Agena Astro and costs $68.00. 

 

EDIT - Ooops! Both of those have male 68mm threads.  So you will also need a 68mm female coupler. Part # 2458195.  It makes the visual back about 8mm longer, but it should still be better and shorter than the ClickLock.

 

HTH,

 

Ron

Edited by RAKing, 04 March 2024 - 10:52 AM.

[denis0007dl]

Thats true, many combinations possible to play with + there is always possibility to made something custom made, like I usually do....

[RAKing]

One other thing to think about.  Unless you attach your diagonal directly to the SCT, you will need enough depth with your SCT visual back to cover the insertion of the diagonal's nosepiece.

 

The Baader T2 nosepiece is nice and short, and I use an old 2-inch TeleVue "Shorty" SCT visual back with my C8 and 6-inch Mak.

 

Blue Fireball makes a simple visual back with two screws that is a bit shorter than the regular SCT VBs.  It's only $35.00 at Agena and might work fine for you.

 

https://agenaastro.c...-2-adapter.html

 

 

 

[denis0007dl]

One other thing to think about.  Unless you attach your diagonal directly to the SCT, you will need enough depth with your SCT visual back to cover the insertion of the diagonal's nosepiece.

 

The Baader T2 nosepiece is nice and short, and I use an old 2-inch TeleVue "Shorty" SCT visual back with my C8 and 6-inch Mak.

 

Blue Fireball makes a simple visual back with two screws that is a bit shorter than the regular SCT VBs.  It's only $35.00 at Agena and might work fine for you.

 

https://agenaastro.c...-2-adapter.html

That would be best option I would choose and like besst!

[tturtle]

This is how I prefer to attach the binoviewer to my 9.25 SCT.  The Baader heavy duty quick changer and a very simple adapter ring to match the SCT threads. Very short, very secure and easy to adapt to different scopes.  This configuration is so secure that I often move the scope across the skies by just pushing on the binoviewer.  This really provides the feeling that you are flying through space. 

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Edited by tturtle, 04 March 2024 - 12:44 PM.

[denis0007dl]

This is how I prefer to attach the binoviewer to my 9.25 SCT.  The Baader heavy duty quick changer and a very simple adapter ring to match the SCT threads. Very short, very secure and easy to adapt to different scopes.

Love it!

[cahanc]

I will probably see if I can get an AM5 in a year

I  use the AM5 with ASIAIR+ almost always when doing visual observing and love it. I do star hop now and then but if pressed for time at all being able to use go-to is nice. 

[RAKing]

This is how I prefer to attach the binoviewer to my 9.25 SCT.  The Baader heavy duty quick changer and a very simple adapter ring to match the SCT threads. Very short, very secure and easy to adapt to different scopes.  This configuration is so secure that I often move the scope across the skies by just pushing on the binoviewer.  This really provides the feeling that you are flying through space. 

 

You win the award for the shortest possible coupler.  Great idea!

 

Thanks,

 

Ron

[cahanc]

The combination of an eq goto mount and a binoviewer is not something I am comfortable with since the binoviewer is so heavy and awkward balance wise. Your near disaster is one reason I prefer an alt az totally manual configuration where the BV rig is always oriented the same way as you move around the sky and, as noted, with the weight always tightening the connections.

The AM5 with 4" refractor, Denk super 27 is a solid combo that I use all the time. Concrete pier which makes a difference, its a great set up for me. 

[Kim2010]

The AM5 can be used both on Alt-Az and GEM modes right?

[Kim2010]

Wait, let me summarize first as I am a bit lost in the field of answers so to speak:

 

These are the weak points and possible solutions esp when using a GEM which points the BV in different angles/directions:

 

1) Connection from visual back to SCT --> I am not sure there is a solution yet?

2) Connection from visual back to Diagonal --> solutions include Clicklock or double/triple thumbscrew visual backs

3) Connection from Diagonal to BV --> I am not sure there is a solution yet?

 

So I think what I need is solutions to (1) and (2). Most of the answers I read are solutions to the connection between visual back and diagonal.

[donniesoprano]

Wait, let me summarize first as I am a bit lost in the field of answers so to speak:

 

These are the weak points and possible solutions esp when using a GEM which points the BV in different angles/directions:

 

1) Connection from visual back to SCT --> I am not sure there is a solution yet?

2) Connection from visual back to Diagonal --> solutions include Clicklock or double/triple thumbscrew visual backs

3) Connection from Diagonal to BV --> I am not sure there is a solution yet?

 

So I think what I need is solutions to (1) and (2). Most of the answers I read are solutions to the connection between visual back and diagonal.

They're all solved in one way or another by products on the market, and depending on your desire for security, by performing  modifications.

 

1. The Denk IVB Powerswitch Diagonal has set screws that bite into the male threads of the SCT.

2. You could use a SCT threaded diagonal to overcome this.  The Denk mentioned above also overcomes this.

3. Using dovetails or threads is the most secure.

 

Another advantage to the Denk Diagonal mentioned is that the IVB prevents rotation of the diagonal WRT the SCT with the interlocking teeth, particularly on the right hand thread side.

 

All of the above (and other threaded methods of mating) can be further solidified by drilling holes through both parts and either tapping them and putting a screw in place to secure them together, or drilling the outer mating side, and using a setscrew to hold the threads of the inner mating side.  I would also suggest removing compression rings.  They're mostly for vanity and IME don't hold as well as direct setscrews, particularly when there are tapered nosepieces involved.

 

Overall though, the best solution is to be cognizant of your BV orientation and overall tightness of all retaining screws through the optical train when slewing and observing.  If you have doubts in your setup, then supporting the binoviewer while slewing is also advised.

 

Finally, this issue is not unique to binoviewers as the same issues exist for significantly heavy mono eyepieces, like (I'm sure there's others):

• 31 Nagler 2.2 lbs
• 21 Ethos 2.25 lbs
• 30mm ES 82 degree 2.2 lbs
• 30mm Meade Series 5000 UWA: 3 lbs
• 31mm Celestron Axiom LX 3.1 lbs

 

ds

[Kim2010]

They're all solved in one way or another by products on the market, and depending on your desire for security, by performing  modifications.

 

1. The Denk IVB Powerswitch Diagonal has set screws that bite into the male threads of the SCT.

2. You could use a SCT threaded diagonal to overcome this.  The Denk mentioned above also overcomes this.

3. Using dovetails or threads is the most secure.

 

Another advantage to the Denk Diagonal mentioned is that the IVB prevents rotation of the diagonal WRT the SCT with the interlocking teeth, particularly on the right hand thread side.

 

All of the above (and other threaded methods of mating) can be further solidified by drilling holes through both parts and either tapping them and putting a screw in place to secure them together, or drilling the outer mating side, and using a setscrew to hold the threads of the inner mating side.  I would also suggest removing compression rings.  They're mostly for vanity and IME don't hold as well as direct setscrews, particularly when there are tapered nosepieces involved.

 

Overall though, the best solution is to be cognizant of your BV orientation and overall tightness of all retaining screws through the optical train when slewing and observing.  If you have doubts in your setup, then supporting the binoviewer while slewing is also advised.

 

Finally, this issue is not unique to binoviewers as the same issues exist for significantly heavy mono eyepieces, like (I'm sure there's others):

• 31 Nagler 2.2 lbs
• 21 Ethos 2.25 lbs
• 30mm ES 82 degree 2.2 lbs
• 30mm Meade Series 5000 UWA: 3 lbs
• 31mm Celestron Axiom LX 3.1 lbs

 

ds

Thank you for that!
 

I guess you'd need to spend more So for now, I will probably just touch the BV when the scope is slewing and position it upright when ready to view-- a bit of a hassle, but worth it I guess for safety!

[Kim2010]

Will either of these work for a more secure and rotation-free BV connection to my C8?

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[RAKing]

Will either of these work for a more secure and rotation-free BV connection to my C8?

 

Both of these are nice visual backs and I have used both of them over the years.

 

But both of these screw onto the SCT threads at the back of every SCT, as well as many other catadioptric designs, such as Maks, etc.  So, if you fasten anything into these with a long heavy moment arm - such as a big heavy eyepiece, a heavy eyepiece inserted into a Barlow, or a binoviewer with heavy eyepieces - there is a possibility that the threads could break free, and the piece could rotate.

 

A small drop of blue Loctite might help.  Then you might need a strap wrench to remove the visual back someday.

 

Cheers,

 

Ron