71 replies to this topic

[raadoo]

Hello everybody

I am getting into astrophotography and I am an admirer of Japanese optics. I have quite a lot of Nikon lenses (close to 30) and I would like to buy a Borg, but I get confused with the modularity of the Borg system. I know there are diagrams but is there any place I can read a bit more about the different choices? 

Regards

JA

The official Borg website has a pretty comprehensive view of how the system works: https://kenkoglobal....ml#rec458391766

[sctchun]

Yes Canon Optron produces them for both brands. Before I bought the double refractor I read EVERY single post on the entire web that I could find on the 107FL and a lot of people claimed that they show horrible color on planets, moon and brighter stars. I can go up to 171x and see color on Sirius and Rigel only and only a little bit more than my AT92mm triplet + mirror diagonal produces. So far I must say it is a non issue taking into account that you will even see color on these stars with a newton telescope since eyepieces and atmosphere are producing color as well. Other than that the Borgs have a better build quality than the Taks I have seen before (okay I have feather touch focusers but also the tubes and dew shields are build like a tank without any mechanical play). And the Borgs generate tons of sharp, contrasty details : )

I find for visual purposes, the Baader BHSS (mirror) diagonal works better than a prism (I have a Baader Zeiss Prism diagonal as well).  From what I've read, prisms are good for longer f-ratio scopes which I can attest to.

[25585]

Not for me, Frauhoferphobia 

[Dr Arnheim]

I find for visual purposes, the Baader BHSS (mirror) diagonal works better than a prism (I have a Baader Zeiss Prism diagonal as well).  From what I've read, prisms are good for longer f-ratio scopes which I can attest to.

I have EMS modules on my Borgs (so 2 mirrors) and I can't mount a prism diagonal on the set-up of the double refractor. If I could I would definitely do it just out of curiosity. I have also read again and again that a prism diagonal adds color to fast cones of light (fast refractors), however, I think it depends also on the quality of the prism. I have a Baader amici prism and a Denkmeier mirror diagonal that I use with my f/5.5 AT92mm triplet. Does the Baader prism add color? Maybe, but definitely not more than an eyepiece does. 

On the other hand prisms have the advantage of scattering less light and don't deteriorate with age.

[Dr Arnheim]

Maybe this is well known here but I just discovered the official Borg blog. In case your Japanese is a little rusty (like mine) you can still read the articles with google translate or deepL. I think you have to consume the information with a pinch of salt since it is coming from Borg itself but I found the blog posts super interesting (f.i. how Mars and Jupiter look through my 107FL at 375x : ).

[K-night]

BORG BINOKIT 72FL 

 

 

I watch raptors perched in/on power towers made of steel girders that provide straight lines for reference, and I don't see the extreme field curvature that short fast scopes are supposed to have when using 2" eyepieces. I did side by side comparisons with a 102mm f/7 FPL-53 triplet and I couldn't detect significant differences in distortion.

 

 

 

In daylight, contrast & resolution through these lenses is outstanding.

Edited by K-night, 07 April 2025 - 03:33 PM.

[Dr Arnheim]

Super nice set-up. Under dark skies with wide field eyepieces this must be a dream.

[K-night]

72 FL single version.

[Bomber Bob]

... the Borgs have a better build quality than the Taks I have seen before ...

 

My 5 TAKs have far superior build quality than my BORG -- and they're much older (1972 - 1988) & seen more use.  I can't imagine TAK selling an all-plastic eyepiece turret; or, all plastic eyepieces, for that matter.  Metal is scarce on the BORG.

 

OTOH, I can sweep the Milky Way with my K10-76 without a mount -- sit comfortably in my lawn chair, and hold the scope with my left hand, and point & track with my right.  Can't do that with either my FC-76 or Mizar GT-80S.  If I want more precision focusing than the R&P, I can swap that module with a very fine BORG Helical -- at a very reasonable price, too.  (Look at all the TAK parts & accessories are Too Darn Expensive!! posts on the Takitis! Thread.  A bunch of them are mine!)  And, as I've posted before, I can swap out the original ACH for an ED or a Fluorite...

 

But, what about The Views??  The BORG has surprised me.  Bright fields, and relatively flat for an F6 ACH.  Same micro-dot stars in the COF as my GT-80S -- at about half the weight.  Most nights, I load it up with my RKEs 28mm / 21mm / 8mm + AT/UWA 10mm.  So easy to sweep, and zoom-in.

[Dr Arnheim]

... the Borgs have a better build quality than the Taks I have seen before ...

 

My 5 TAKs have far superior build quality than my BORG -- and they're much older (1972 - 1988) & seen more use.  I can't imagine TAK selling an all-plastic eyepiece turret; or, all plastic eyepieces, for that matter.  Metal is scarce on the BORG.

 

OTOH, I can sweep the Milky Way with my K10-76 without a mount -- sit comfortably in my lawn chair, and hold the scope with my left hand, and point & track with my right.  Can't do that with either my FC-76 or Mizar GT-80S.  If I want more precision focusing than the R&P, I can swap that module with a very fine BORG Helical -- at a very reasonable price, too.  (Look at all the TAK parts & accessories are Too Darn Expensive!! posts on the Takitis! Thread.  A bunch of them are mine!)  And, as I've posted before, I can swap out the original ACH for an ED or a Fluorite...

 

But, what about The Views??  The BORG has surprised me.  Bright fields, and relatively flat for an F6 ACH.  Same micro-dot stars in the COF as my GT-80S -- at about half the weight.  Most nights, I load it up with my RKEs 28mm / 21mm / 8mm + AT/UWA 10mm.  So easy to sweep, and zoom-in.

As said, this impression might be only due to the standard focuser of the Taks. I had a FOA 60 for some days and the focusing knob felt like plastic (I guess it is made of plastic - isn't it)? I can't judge on the the standard focuser of the Borgs since Beat Kohler delivered the tubes with feather touch focusers which I really love (though the best focuser I've ever tried is the Baader Steeltrack). 

[desertlens]

BB, Your comment was, 'Metal is scarce on the BORG'. I have several Borgs and have yet to find any plastic components anywhere in the design.

 

Dr. A, The Takahashi focuser knobs are aluminum.

Edited by desertlens, 01 May 2025 - 06:44 PM.

[Dr Arnheim]

Hello Craig,

 

According to Rodger Vine you are right: the FOA-60 has an aluminum focuser knob, but: "The FS-60Q, like the old FC-60 and new FC-76, has the cheapo hollow-plastic imitation focuser knobs, but the FOA-60 gets the proper anodised silver metal ones like other Tak’s. The matching silver knob on top of the focuser is the standard Takahashi lock: progressive and shift-free." Btw, I absolutely love Taks and only don't own one because I tell myself everyday that I don't need another scope. But I would love to own a FC-100DZ only to compare views with it to all of my other scope the entire night 

[desertlens]

Dr A, My FS-60Q has aluminum knobs as well. Takahashi follows their own unique path, which is often unpredictable.

 

 

[desertlens]

Here's one for Bomber Bob who seems inclined to older models. One user reported some CA but frankly, I don't see it.

 

Borg 89ED

[Lagrange]

BB, Your comment was, 'Metal is scarce on the BORG'. I have several Borgs and have yet to find any plastic components anywhere in the design.

 

Dr. A, The Takahashi focuser knobs are aluminum.

I think older Borg scopes and components often used plastic components, and in the early days were mostly plastic. Over the years they've transitioned to using all-metal construction while retaining their focus on keeping weight down.

 

My 90FL's objective unit is all-metal, but beautifully made and very lightweight.

[Dr Arnheim]

Here's one for Bomber Bob who seems inclined to older models. One user reported some CA but frankly, I don't see it.

Borg89ED.jpg
Borg 89ED

That is a beautiful scope.

In my 107FL I can only see color in harsh daylight conditions (branches against a blue sunny sky) or Rigel and Sirius so totally insignificant in my opinion. I can also push the magnification to 250x and the image stays sharp.
Nevertheless, I would love to compare it to a longer focal length scope side by side to see what the trade off of the shorter focal range really is.

[K-night]

Hello BORG collective, I need help managing my OC tendencies.

 

The 9868 LMF-1 focuser I'm using with my 72 FL single is missing a thumb screw.

 

My guess is that it would have been a focus lock/stopper screw that may have had a nylon or Delrin tip, or pad on the end, and it would have pressed against the draw tube roller plate. Has anyone seen one of these legacy focusers and know what the end of the missing thumb screw looked like? I've reached out to Ted with no luck btw.

 

This image from the web appears to show a defined scuff line down the center of the roller plate.

 

The Kasai and TS-Opitcs V-Power Crayford have a similar looking focuser with a thumb screw in the same place. Anyone have experience with one of those focusers?

 

Follow up info:

Thanks to desertlens for sharing that the focus lock thumbscrew on his Kasai V-Power Crayford has a polished flat bare tip. However, the V-Power screw is larger in diameter than the one on the BORG focuser. Only the thumbscrew location is similar. 

Mr. Kasai informed me the factory producing these Crayfords closed several years ago and no spare parts for either are available.

So far I haven't experienced slipping, but if it were to happen I've located a locking thumbscrew alternative at McMaster-Carr.

Edited by K-night, 03 May 2025 - 04:18 PM.

[Bomber Bob]

BB, Your comment was, 'Metal is scarce on the BORG'. I have several Borgs and have yet to find any plastic components anywhere in the design.

 

Dr. A, The Takahashi focuser knobs are aluminum.

The entire outside of my K10-76 is plastic:

 

 

Ditto for the eyepiece shells & photo-related tubes & such.

Edited by Bomber Bob, 02 May 2025 - 05:15 PM.

[skyops]

I think older Borg scopes and components often used plastic components, and in the early days were mostly plastic. Over the years they've transitioned to using all-metal construction while retaining their focus on keeping weight down.

 

 

*

 

Perhaps. 

 

My first Borg was bought new June 2001. Metal components.

 

 

 

 

.

[Bomber Bob]

IDK when my BORG was made.  The plastics are quality versions:  No seams, and no artifacts from molds / castings.  They're scuff & scratch resistant, too.  After a quick wipe-down with Windex & a cotton rag, they're as glossy as new.

 

The threaded collars that join the modules are metal.  But... the Lens Cell outermost band is plastic, and at some point in the past, it cracked.  Doesn't affect performance, and it didn't hurt the objective, but it doesn't give me a warm fuzzy, either.

[rerun]

I also own some Borg refractors and I love them. They are so small but the pictures are so sharp. I have a Borg 71FL and two Mini Borg 50 refractors. They all get a lot of sun- and starlight.

 

 

[K-night]

72 FL in backyard birding mode.