Borg 72 fl

[Ken82]

Has anyone purchased the borg 72 scope yet? Any feedback?

I want something in the 60-70mm bracket to take abroad so it needs to be as light/small as possible. 

Thanks Ken 

[Andrew_B]

I can't help you with the Borg 72 unfortunately, but a scope you might also want to look at is the Takahashi FC-76DCU which has a split tube and can be unscrewed to make it much shorter for travel.

It has a longer focal ratio than the Borg (f7.5) and heavier but is still a very light scope. It's very highly regarded and SGL member @DirkSteele wrote an excellent review of the scope (as well as the smaller FS-60CB and FS-60Q models) on his website http://alpha-lyrae.co.uk/category/equipment-reviews/. Roger Vine also praised the scope in his review http://www.scopeviews.co.uk/TakFC-76.htm and selected it as his best buy 3" refractor.

Every review I've seen has been very positive and was enough to convince me to buy one. It's currently sitting in my lounge tormenting me because the focuser hasn't arrived yet - I've assembled mine from parts rather than bought the off the shelf scope.

[Stu]

I would certainly agree that the FC-76 is a lovely, and very sharp scope. I too built up a unit from parts with a Feathertouch focuser and really liked it. Took it abroad a couple of times too.

[JeremyS]

+1 for Tak FC 76 DCU. Had one for 3 years and taken all over the world.

Never been impressed with Borg. Only had one, a Borg 125 which was under engineered. Nice concept (modular), though.

Edited July 31, 2021 by JeremyS

[Ken82]

15 hours ago, Andrew_B said:

I can't help you with the Borg 72 unfortunately, but a scope you might also want to look at is the Takahashi FC-76DCU which has a split tube and can be unscrewed to make it much shorter for travel.

It has a longer focal ratio than the Borg (f7.5) and heavier but is still a very light scope. It's very highly regarded and SGL member @DirkSteele wrote an excellent review of the scope (as well as the smaller FS-60CB and FS-60Q models) on his website http://alpha-lyrae.co.uk/category/equipment-reviews/. Roger Vine also praised the scope in his review http://www.scopeviews.co.uk/TakFC-76.htm and selected it as his best buy 3" refractor.

Every review I've seen has been very positive and was enough to convince me to buy one. It's currently sitting in my lounge tormenting me because the focuser hasn't arrived yet - I've assembled mine from parts rather than bought the off the shelf scope.

Thanks for the feedback everyone 👍

The takahashi 76dcu does look good although I think it’s much heavier than the Borg 72 ? 
 

I wanted to keep the weight as low as possible for flights etc so it was a straight choice between the Borg 72 and tak 60. Although these are both around the same weight (1.2kg) so I opted for the Borg. 
 

Thanks Ken 

[Andrew_B]

1 hour ago, Ken82 said:

Thanks for the feedback everyone 👍

The takahashi 76dcu does look good although I think it’s much heavier than the Borg 72 ? 
 

I wanted to keep the weight as low as possible for flights etc so it was a straight choice between the Borg 72 and tak 60. Although these are both around the same weight (1.2kg) so I opted for the Borg. 
 

Thanks Ken 

Glad to hear you got it sorted. The Tak FC-76DCU is heavier than the Borg 72 at 1.9kg for the OTA -  not a lot in absolute terms but it is 58% more weight.

Borg fluorite optics are made by Canon Optron, same as Takahashi and they're of similarly high quality. Borg seem to prefer faster focal ratios for their scopes to keep size and weight down and make them better astrographs, although it does mean more field curvature and slightly less colour correction but from what I've read the difference isn't dramatic.

Let us know what the Borg 72 is like when you've had a chance to try it out. They make some really interesting scopes but there aren't many user reports on here and I'd imagine there'd be plenty of interest.

[Ken82]

18 minutes ago, Andrew_B said:

Glad to hear you got it sorted. The Tak FC-76DCU is heavier than the Borg 72 at 1.9kg for the OTA -  not a lot in absolute terms but it is 58% more weight.

Borg fluorite optics are made by Canon Optron, same as Takahashi and they're of similarly high quality. Borg seem to prefer faster focal ratios for their scopes to keep size and weight down and make them better astrographs, although it does mean more field curvature and slightly less colour correction but from what I've read the difference isn't dramatic.

Let us know what the Borg 72 is like when you've had a chance to try it out. They make some really interesting scopes but there aren't many user reports on here and I'd imagine there'd be plenty of interest.

Ah sorry Andrew my last message was misleading. 
 

I haven’t bought the Borg yet although at this moment it would be my preference for the reasons stated above. 
 

My travel scopes at the moment are  a SW 72ds and fsq 85. Both are great but just a bit too heavy when trying to save every ounce for a flight. 
 

I was just hoping to maybe get some first hand feedback before taking the plunge, I know the Borg 72 is relatively new. 
 

Ken 

[Andrew_B]

2 hours ago, Ken82 said:

Ah sorry Andrew my last message was misleading. 
 

I haven’t bought the Borg yet although at this moment it would be my preference for the reasons stated above. 
 

My travel scopes at the moment are  a SW 72ds and fsq 85. Both are great but just a bit too heavy when trying to save every ounce for a flight. 
 

I was just hoping to maybe get some first hand feedback before taking the plunge, I know the Borg 72 is relatively new. 
 

Ken 

Gotcha. It does sound like the Borg is your best option since you've already got something of similar weight to the Tak in your SW 72DS so if that's a bit heavy then the FC-76DCU won't be any better other than its split tube.

I was going to suggest trying the forums on Cloudynights because I've not seen anyone on here saying they own a Borg 72, but having done a search I couldn't find anything on there either. Presumably sales have nearly all been in Japan which would explain the lack of info from the usual English language sources. The best I can suggest is to try reviews for other Borg scopes like the 67FL and 71FL - Roger Vine talks about the former on his site and was full of praise so if they can get a fluorite doublet right at f4.5 then a 72mm f5.6 should be a safe bet (for image quality at least).

As you already know, the only comparable scope in that weight range seems to be the Tak FS-60CB which I think is 1.3kg standard or 1.6kg for the f10 Q version. It's more of a known quantity and in Q mode it should be visibly better corrected but you'd losing a bit of aperture and gaining a few hundred grams which is a tradeoff I don't think you'd want.

[marcus_z]

Ken, if the 71FL is an option for you, I can offer you an objective lens assembly. For reference, you can find professional measurements of a 71FL here: Wellenform - Zertifizierte Fernoptik - Objektive - Angebot. Their conclusion is: "When focusing on green (546nm), blue (486nm) is very well diffraction-limited, and yellow (589nm) almost diffraction-limited. Red (656nm) is defocused and is therefore below the diffraction limit of 0.80 strehlpoints. Because perception of red is weak in the dark, the red color fringes (resulting from the defocusing of red) can only be seen very faintly, if at all." I think that conclusion is right and resembles my experience at the eyepiece.

The 71FL is shorter and lighter than the FC-76D. If deep-sky is your priority, the 71FL/72FL might be more interesting for you, for shallow-sky the 76D might be more interesting. One thing is sure, the 71FL offers more aperture and less weight than the FS-60CB (at a higher price).

[Ken82]

I received my Borg 72 this week and decided to mount it on my dob for the time being as it’s very light. 
 

I've added a 2kg counter weight which balances perfectly whilst using an ethos 21 in the dob and luminos 23mm in the Borg. Unfortunately the Borg doesn’t have enough inward travel to focus with the ethos but hey ho no problem the luminos works well.

Im assuming  most people will be imaging with the scope with the flattener although I only plan to use it visually. 
 

Very slight yellow fringe on the moon but very pleasing view (much better than my skywatcher 72ed). Although it’s maybe a poor comparison as the focal lengths are different and of course the price ! 
 

Very well made little scope and I’m really happy I have a new travel scope 😀 

 

[Concordia000]

Hi Ken,

I will be very interested in your experience with the 72FL. I got rid of my 90FL which was a fantastic scope, but had a bit too much CA to be a good astrograph. I also hear Borg f’d up the matching reducer with the 90FL so it shows a lot of CA, but they fixed that with the 72FL. I got a NP-101 instead and *then* I realised it’s so heavy and hard to move around.

So now I need a portable scope again and I am staring very, very hard at the 72FL which apparently controls CA better than the 90FL. I also have a Feathertouch focuser already and I only need the lens assembly and the tube.

Also, if you are struggling with in-focus, you can always buy an 150mm Borg tube and add extension tubes to achieve focus.