Svbony 70mm Mini Mak

[johninderby]

Svbony SV41 70mm Mini Mak

Was looking for super pprtable setup and as I just don’t get on with bins decided a monocular or similar would be more suitable. Came across the little 70 Svbony mak and decided it would fill the bill and was quite inexpensive as well. Nothing fancy but good enough with a BAK4 prism and claim of  99.5%;  light transmission. Waterproof and nitrogen purged with a rubber armour coating on the outside.

The usual problem with these mini maks though is a so so zoom eyepiece so decided to adapt it to take any 1.25” eyepiece. Bought a cheap M48 to T2 adaptor so I could fit a T2 to 1.25” eyepiece adaptor. Fortunately the adaptor was a perfect fit on the scope. 🙂

Already had a suitable lightweight but surprising sturdy tripod with a fluid head. Still undecided about what sort of finder would suit. Perhaps a Rigel Quickfinder? 🤔

Brief daytime test shows the optics are pretty good. About on a par with the little Skymax maks. The stock zoom is actually not that bad but trying a Nirvana 16mm eyepiece showed the difference a decent eyepiece makes.

Correction:

Have since found that the M48 threaded adaptor ring is removable which then allows direct fitting of a T2 adaptor.

 

 

 

 

 

Edited November 17, 2021 by johninderby

[Alien 13]

That Mak is soooo cute.

Alan

[davyludo]

Interesting...I've been trying to think about a tiny setup to take wild camping with me. This might be worth looking at! 

[Andrew_B]

Just looked at the Svbony website for the specs (it's in the hunting->spotting scopes section) and it's a very compact and lightweight package. Price isn't bad either.

70mm f/11.2 and 792g which I presume is with the included eyepiece.

[johninderby]

For the price it seems quote good. Will have to take a few daytime pics and see how it does for astro use. Will try a couple of zooms to see how the stock zoom compares. Fortunately has an M48 thread so easy to adapt for regular eyepieces. A standard 1.25” to 2” adaptor will also screw right on but is a bit bulky.

https://www.amazon.co.uk/Svbony-Maksutov-Multi-Coated-Waterproof-Telescope/dp/B07GN9LL61

 

Edited October 13, 2021 by johninderby

[badhex]

Looks great as a little grab and go! Really interested to hear how it performs under the night sky.

What's the built in mounting plate like? Sturdy?

[johninderby]

4 minutes ago, badhex said:

Looks great as a little grab and go! Really interested to hear how it performs under the night sky.

What's the built in mounting plate like? Sturdy?

Brass threaded bushing and seems pretty solid. 

[PeterW]

Interesting, Svbony seem to be rapidly expanding their offerings with some well  though of products appearing.

How big is the prism below the eyepiece, may limit the use of long and wide eyepieces. The 24mm panoptic/ES68/UFF would test this, maybe a narrower long eyepiece would be needed. I assume the supplied zoom is very strawlike… why do companies always supply bad, narrow zooms with no obvious way to use astro eyepieces, even though many can be adapted, as you’ve shown!

Is there much images  shift when focussing?
What is the contrast like, some people note that the design is very hard to baffle well.

Be good to hear more about how it performs, especially on the daytime.

 

Peter

 

[johninderby]

Didn’t notice any image shift in the brief test I did yesterday. Will be experimenting with a few eyepieces today to see if viginating is a problem and see what I think about contrast etc.

[johninderby]

Compared some eyepieces.

The stock zoom seems to have the same fov as a typical 8 - 24 zoom and so certainly usable. Tried a Svbony 10 - 30 zoom which was a better performer with a slightly brighter image. Well matched to this scope.

Then compared a 15mm Plossl with a 16mm Nirvana. The increase in fov was as expected  going from a 50 degree eyepiece to an 82 degree one. Vignetting with the Nirvana wasn’t really noticeable. Image was brighter and sharper with the Nirvana though but again that was as expected. 

The prism is small (about 15mm) but similar size to the baffle tube. Found daylight images were sharp with good contrast when using the Nirvana.  

So upgrading the eyepiece is recommended but the stock zoom is certainly usable but keep in mind if fitting the 1.25” adapter the stock zoom won’t be usable due to it’s smaller than 1.25” barrel. Image brightness, sharpness and contrast were good overall and better than expected for this inexpensive little mak.

Pleased with the little mak so far and given it’s price and small aperture seems great value.

Edited October 14, 2021 by johninderby

[nfotis]

Intriguing.

So, what's the smallest Mak which can accept directly 1.25" eyepieces?

N.F.

[johninderby]

6 minutes ago, nfotis said:

Intriguing.

So, what's the smallest Mak which can accept directly 1.25" eyepieces?

N.F.

As far as I know all currently available 70mm maks need an adaptor to accept 1.25” eyepieces. The Celestron C70 comes with the 1.25” eyepiece adaptor. There is the Acuter Maksey 60 but the diagonal is smaller than 1.25”.

Edited October 14, 2021 by johninderby

[Louis D]

1 hour ago, nfotis said:

Intriguing.

So, what's the smallest Mak which can accept directly 1.25" eyepieces?

N.F.

There is the older PICO-6 60mm Maksutov, of which I have a used copy, that can accept 1.25" accessories natively.  However, the optics have severe spherical aberrations visible at anything above the lowest power possible, so it's more of a conversation piece for me.

[johninderby]

7 minutes ago, Louis D said:

There is the older PICO-6 60mm Maksutov, of which I have a used copy, that can accept 1.25" accessories natively.  However, the optics have severe spherical aberrations visible at anything above the lowest power possible, so it's more of a conversation piece for me.

Hmmmm………… remove the insides and use it as a beer stein perhaps? 🤔

 

Ah a good old root beer. Hard to get hold of in the UK and expensive when you can find it. One soft drink that never caught on here.

[Louis D]

25 minutes ago, johninderby said:

Ah a good old root beer. Hard to get hold of in the UK and expensive when you can find it. One soft drink that never caught on here.

Even better as a root beer float with a couple of scoops of vanilla ice cream.  Yummy!

[Louis D]

16 hours ago, johninderby said:

A standard 1.25” to 2” adaptor will also screw right on but is a bit bulky.

That means a 2" eyepiece with filter threads could be screwed onto the back as well.  You should try a max field eyepiece with a ~46mm field stop diameter on it for giggles to see how much it vignettes. 😁

[johninderby]

Would look “interesting” with a 31mm Nagler then. 😁😁😁😁

Edited October 14, 2021 by johninderby

[johninderby]

5 minutes ago, Louis D said:

Even better as a root beer float with a couple of scoops of vanilla ice cream.  Yummy!

Stop please. Used to love root beer while in Canada. 

Ouch 🙀🙀🙀

[johninderby]

Quick smartphone image taken from the bedroom window of a car grille on the next street through the trees. Makes a change to chimney pots. 😁

 

Edited October 14, 2021 by johninderby

[PeterW]

Nice. Bet the  31mm terminagler would be bigger than the scope itself!

I was looking at a mak for high power spotting, but was put off by low contrast concerns. This sounds like it could make a good light “alternative” to a larger spotter for times you want to travel Light.

Could you post links to the adapter the r and 1.25” adapter you are using

Would need a light tripod or hide clamp to use well as the high magnifications need stability. No point having a lighter scope and needing a heavier tripod 😞 Maybe you could just rest it against stuff… like camera users did with their beanbags….

Peter

 

 

[johninderby]

You would fit the scope to the 31mm Nagler not the eyepiece to the scope. 😁

M48 to T2 adaptor

https://www.harrisontelescopes.co.uk/acatalog/m48t2.html#SID=1664

This is the T2 eyepiece holder. 365astronomy used to sell it but can’t find it on their site. Any T2 to 1.25” adaptor with a 35mm length would do. Perhaps a Baader one?

https://www.astroshop.eu/other-adapters/ts-optics-adapter-of-t2-on-1-25-put-on-t2-thread-35mm-overall-length/p,11259

[PeterW]

So the back focus distance needs to be around this for a range of eyepieces to come to focus?

Peter

[johninderby]

It’s actually down to having enough length for the eyepiece barrel to fit. The opening in the back of the scope is slightly under 1.25”. As a mak has plenty of focus travel this shouldn’t be a problem.

[Louis D]

2 hours ago, johninderby said:

This is the T2 eyepiece holder. 365astronomy used to sell it but can’t find it on their site. Any T2 to 1.25” adaptor with a 35mm length would do. Perhaps a Baader one?

Found this available in the US:

Blue Fireball Eyepiece Holder (1.25") with T / T2 Female Thread (T2 Visual Back) # E-10

And if you want a 2" to T2 visual back:

Blue Fireball Eyepiece Holder (2") with T / T2 Female Thread (T2 Visual Back) # E-09

[Louis D]

On 13/10/2021 at 09:02, johninderby said:

On closer inspection of this photo, I realized that you'd need an M48 spacer ring (empty filter ring) to keep the field lens of some 2" eyepieces from crashing into that raised metal ring inside the M48 thread if you tried to screw the eyepiece directly to it.  Legitimately, I could see attaching an 12mm ES-92 to it with minimal vignetting, although I'd probably go the route of the 2" to T2 thread visual back for quicker eyepiece swaps.  Of course, the eyepiece would weigh more than the entire scope (1011g for the 12mm ES-92 vs. 792 for the Mak).