6 replies to this topic

[Procyon]

Attaching and aligning a 50mm Mini Borg (Or other small refractor) to an SCT 

 

I'm trying to add a small refractor and create a superfinder like Televue calls it here: X-Y Mount Superfinder System

 

The little borg already has mounting rings or clamps which is great because I never

liked those overly sized rings with all the screws and stuff sticking out.

 

The bottom holes are regular 1/4 - 20. I'm trying to find the proper mounting plate and shoe 

that will fit in a regular vixen base tail. Not sure if it's a Synta or an Agena version I have on my 11" CPC SCT.

 

I'd like to align it with the view of the main scope.

The little finderscope barely weights half a pound so no weight or balancing issues, it take a 1.25" diagonal also.

 

Does anyone have a preferred method or way of making all this happen?

 

Is the Televue X-Y mount kit the way to go? Nice video here that goes more into depth using this method: https://www.youtube....h?v=mpt0T4TOIng

 

https://agenaastro.c...t-aac-0002.html

 

There's also the Celestron Universal Piggyback Mount but you can't adjust the finder upwards or downwards,

just side to side. But it's also 1/3 the cost. If the Borg gives me a 6.5º TFOV with a 30mm Celestron Ultima,

how off do you think I'll be?

 

I see all these shoes, risers, bases, rails, tails and have about 20 windows open with all these things,

is there any other way to get this done? Anyone feel like looking at all this:? 

 

https://www.bhphotov...etail_base.html

https://www.admacces...vetail-adapter/

https://www.scopestuff.com/ss_rdp1.htm

https://www.telescop...8450364038.html

https://www.testar.c...=40342340141248

https://agenaastro.c...e-2457000a.html

https://astronomical...r-finderscopes/

https://www.sciencec...iborg/index.htm

https://www.365astro...for-sct-bracket

https://www.sciencec...s/html/8991.htm

https://telescopesca...a-mount-vdup-cm

https://telescopesca...mandy-clamp-ika

https://www.cloudyni.../?p=6148241-835

 

 

Edited by Procyon, 22 June 2025 - 04:20 PM.

[Procyon]

[MikeMiller]

<---- Points at my profile picture.

 

This is my technique:

 

This is a bit of a heavy setup, but it is rock solid 

 

Bold a vixen dovetail plate to the rings, put on an ADM Mini-Max, then on to a vixen rail attached to the SCT OTA.

 

I have custom tube rings on my EdgeHD 8, however it works just fine with any usual Vixen rail attached to the top end of the OTA.

 

I have not used the Televue XY mount, but I have used the Borg one, and did not care for it. The ADM Mini-Max is the best in class.

 

Also I would advise against something like the Celestron mount that has only a single point of contact. There can be a bit of wiggle, that defeats the purpose of excellent dual rings on the Borg.

Edited by MikeMiller, 29 June 2025 - 10:04 PM.

[Procyon]

Ummm yeah, kinda late but no worries, thanks.

 

Eessh, 340$ for the ADM Mini-Max.

 

I went a different route after spending so much time looking for

something after I posted this.

 

Since there's 1/4-20 holes on the two clamp rings,

what I did is order these 3 parts to put on an extra simple finder mounting base I already had on the CPC 1100.

 

https://agenaastro.c...a_s_length=6922

https://www.aliexpre....1e5b1802C4aG8E

https://www.aliexpre....1e5b1802C4aG8E

 

That Ballhead Tripod Mount Adapter seems to hold 8kg? We'll see. But all this for about 25$ looks fine to me and worth a try.

I might need a D-ring Camera Mount Screw also, but maybe not.

 

The whole setup with the borg should weigh about a pound, so it's not much. Maybe 1.5 with a 2" diagonal if I decide to use one.

 

So you prefer straight through huh? 

Edited by Procyon, 29 June 2025 - 10:30 PM.

[MikeMiller]

Like I said, my solution is overkill. But I was fed up with any amount of vibration causing egg shaped stars in my images.

 

I love those adorable mini dovetail bars, I may need to get some. With it attached to both of the rings, it should work great.

 

I wouldn't trust any ball head with 8kg of anything I cared about. One cable snag and the whole thing crashes to the ground. A ballhead is probably overkill for guide scope aiming, too. Really with a 50mm guidescope you should only ever need to move it a few degrees before finding a good star. Especially with today's sensitive CMOS guidecams. I had designed my system back with CCD guidecams that needed to hunt around for good stars.

 

But the problem isn't the carrying capacity. With a single attachment point you get kind of a vibration wiggle between the main OTA and guide scope. Any difference in aiming between the two will show up as aberrations in the image.

 

However it may not matter if it doesn't wiggle enough to show up on your image. If your mount and tripod/pier are solid, you wont have issues. Give it a try and see what happens. Just remember, even if the PHD graph is flat, it doesn't mean the OTA didn't move in relation to the guidescope.

 

With my setup, I can do jumping jacks right next to the mount while imaging and not see any twitch in the guiding

[Procyon]

Like I said, my solution is overkill. But I was fed up with any amount of vibration causing egg shaped stars in my images.

 

I love those adorable mini dovetail bars, I may need to get some. With it attached to both of the rings, it should work great.

 

I wouldn't trust any ball head with 8kg of anything I cared about. One cable snag and the whole thing crashes to the ground. A ballhead is probably overkill for guide scope aiming, too. Really with a 50mm guidescope you should only ever need to move it a few degrees before finding a good star. Especially with today's sensitive CMOS guidecams. I had designed my system back with CCD guidecams that needed to hunt around for good stars.

 

But the problem isn't the carrying capacity. With a single attachment point you get kind of a vibration wiggle between the main OTA and guide scope. Any difference in aiming between the two will show up as aberrations in the image.

 

However it may not matter if it doesn't wiggle enough to show up on your image. If your mount and tripod/pier are solid, you wont have issues. Give it a try and see what happens. Just remember, even if the PHD graph is flat, it doesn't mean the OTA didn't move in relation to the guidescope.

 

With my setup, I can do jumping jacks right next to the mount while imaging and not see any twitch in the guiding

Oh ok, I see, no I'm just using mine for a 2nd visual look, like a much wider look compared to the SCT. Just for fun for visual, I don't take pictures or anything. 

Even if it's off, I'll adjust it, honestly, I don't even know what a ballmount is, hope it doesn't wiggle like some bobblehead thing though.

[MikeMiller]

Ohh, thought you were setting up a guide scope. Yeah this will be more than fine.