Svbony 8-20 Super Zoom

[Mr Spock]

Just out...

[globular]

It looks like it might be an astro adapted version of the Kowa TE-11WZ spotting scope eyepiece.
(Hopefully an official adaptation by the same manufacturer but may just be a copy of their design - svbony do seem to have form in this area).
Certainly very similar specs - focal lengths, AFOVs, eye relief, lens elements and groups….
But probably with the good quality ED glass of the Kowa replaced with something cheaper?
And the nice multi position twist up eyecups replace with flip up / down stiff rubber ones. (Albeit with the nice addition of dioptrx compatibility).

[Ratlet]

Probably better posting in its own thread rather than making the substantial 3-8mm even bigger!

Looks an interesting eyepiece.  Have to admit the price made me suck air through my teeth, but given what you are getting, it is a lot of eyepiece.  As I said previously the fov is in the sweet spot for me for a normal eyepiece.  Absolute beast in size at just over 5" long and 500g in weight.

[Ags]

I won't preorder, but this one has been provisionally added to my wish list.

[Mr Spock]

This, along with the 3-8, could mean a simple two eyepiece set up for many. It will certainly pique the interest in going down that route.

[Zermelo]

It will be interesting to see where the price goes on this one.
I ordered a 3-8mm ahead of launch and expected them to go up after initial favourable reviews, but instead there were various discounts.

[Elp]

The price shall we say, is a bit optimistic? Will it compare favourably to a Baader Hyperion Zoom which I've never used but seems to be popular.

[Ags]

It seems a logical price for a large and complex eyepiece.

[John]

Very interesting development 🙂

The APM 7.7mm - 15.4mm Super Zoom would seem to be the clear target competitor and that is currently priced around £390.00

If the optical performance is of a similar standard to the Svbony 3mm-8mm zoom and the eyepiece can actually be used in the 1.25 inch fitting as conveniently as it can be in 2 inch mode then it could find a place in many eyepiece cases, and possibly lead such cases to be somewhat less populated !

 

[Louis D]

And then there is the newish Laida Zoom (originally Zoin Zoom) which some claim to also be a copy of the Kowa TE-11WZ.   I suspect it might be the same zoom eyepiece repackaged.

Edited July 15 by Louis D

[globular]

The Laida has a different number and grouping of lens elements, different eye relief, and has it's wide fov at 20mm and narrower at 8mm.  

The Svbony and Kowa have the same specs as each other on paper - including having wide fov at 8mm and narrower at 20mm.

Clearly it remains to be seen what the svbony actually delivers in the first few (independent) reviews - but if it's trying to be like the Kowa, and they haven't cut too many corners, it might finally be a zoom to fill that gap in the market that many have been waiting for. We can hope anyway.

It's a shame that Kowa has never embraced the astronomy market, because a real Kowa zoom for astronomers will trump any svbony version (albeit at a higher price).  But, despite many people pleading them to, they haven't - so bring it on svbony and fingers crosses it adds to their small number of very good items rather than expanding their catalogue of lemons.

[Don Pensack]

31 minutes ago, globular said:

The Laida has a different number and grouping of lens elements, different eye relief, and has it's wide fov at 20mm and narrower at 8mm.  

The Svbony and Kowa have the same specs as each other on paper - including having wide fov at 8mm and narrower at 20mm.

Clearly it remains to be seen what the svbony actually delivers in the first few (independent) reviews - but if it's trying to be like the Kowa, and they haven't cut too many corners, it might finally be a zoom to fill that gap in the market that many have been waiting for. We can hope anyway.

It's a shame that Kowa has never embraced the astronomy market, because a real Kowa zoom for astronomers will trump any svbony version (albeit at a higher price).  But, despite many people pleading them to, they haven't - so bring it on svbony and fingers crosses it adds to their small number of very good items rather than expanding their catalogue of lemons.

The Laida Zoom, like all zooms with variable apparent fields, has its narrowest apparent field at low power (57°) and its largest apparent field at high power (76°).

If you've read the opposite, it is simply a typo.

[Ratlet]

4 hours ago, Don Pensack said:

The Laida Zoom, like all zooms with variable apparent fields, has its narrowest apparent field at low power (57°) and its largest apparent field at high power (76°).

If you've read the opposite, it is simply a typo.

As is tradition, it seems, with Chinese eyepieces the spec in the advertising literature is wrong.

I'm in a rough place with this.  Quite fancy it but the price is meaty.  I'm not sure I would qualify it as over priced though?  Obviously that will entirely depend on the performance, but assuming it is as good as the 3-8mm I'd say it was a pretty good price.

[Louis D]

It might be useful in a high f-ratio telescope to fine tune high power views (as in my f/12 Mak), or to put in a travel kit if it doesn't require too much in-focus.  Other than that, I can't imagine swapping my stable of long eye relief, very wide field of view eyepieces for it.  As such, I'm in no hurry to spend $300 (let alone $400) on such an eyepiece.

[Zermelo]

Svbony have posted a couple of Q&As here.

[russ]

On 14/07/2024 at 11:47, Elp said:

The price shall we say, is a bit optimistic? Will it compare favourably to a Baader Hyperion Zoom which I've never used but seems to be popular.

I've never truly grown to love the Hyperion Zoom. Not sure why. But I love my SVbony 3-8mm zoom. Love the build, the clickstop, constant 56deg field and the IQ. The 8-20 will go on the wishlist and wait for a sale. 

[Elp]

It's also infringing on the Pentax XL zoom at 400. 100 for the 3-8mm is one thing, triple for an untested new product is another although I know they do other zooms too so maybe they've sorted out the specs for it.

[Elp]

The only zoom I've used is the Celestron one and it was decent, I didn't however like the narrow view of which this is similar.

[John]

I've used quite a few zooms including the APM "super zoom" which this new one seems to be aimed at competing with. I've also owned a Leica ASPH zoom, a couple of the Baader's, the Svbony 3-8mm, the Nagler 2-4mm and (lately) the 3-6mm) and the Svbony 7-21mm. Not tried a Pentax zoom so far though 🤔

The APM was excellent optically plus quite consistent in it's AFoV across the zoom range although that zoom didn't the quite match the initially hoped for AFoV when production units actually arrived.

My main concern with the APM zoom was that it needed such a lot of inwards focuser movement when used in 1.25 inch mode that many scopes simply can't bring it to focus.

If this new Svbony zoom has similar optical performance characteristics to the 3-8mm zoom and is readily useable in 1.25 inch mode as well as in 2 inch, then I may well be interested 🙂

 

 

 

 

[Highburymark]

I suspect this zoom might be considerably more challenging to design and make than the 3-8 - or at least to meet the standards desired by observers in this area of the astronomy market.
Like the wider range though - that’s what limited the appeal of the Leica and APM, and makes the Baader attractive, despite its narrow afov at low powers.

[JeremyS]

Was about to post what John said: the ability to easily cope with 1.25-inch fitting regarding focuser travel could be a differentiator 

[Second Time Around]

4 hours ago, John said:

I've used quite a few zooms including the APM "super zoom" which this new one seems to be aimed at competing with. I've also owned a Leica ASPH zoom, a couple of the Baader's, the Svbony 3-8mm, the Nagler 2-4mm and (lately) the 3-6mm) and the Svbony 7-21mm. Not tried a Pentax zoom so far though 🤔

The APM was excellent optically plus quite consistent in it's AFoV across the zoom range although that zoom didn't the quite match the initially hoped for AFoV when production units actually arrived.

My main concern with the APM zoom was that it needed such a lot of inwards focuser movement when used in 1.25 inch mode that many scopes simply can't bring it to focus.

If this new Svbony zoom has similar optical performance characteristics to the 3-8mm zoom and is readily useable in 1.25 inch mode as well as in 2 inch, then I may well be interested 🙂

 

 

 

 

From a post on Cloudy Nights about the Laida 8-20mm zoom that is suggested to be the same as the Svbony apart from the housing:

"Focus travel comparisons (on the skyrover apo pro focuser, these numbers only make sense relative to each other):

41.5mm: TV plossl 32mm, APM UFF 18mm, Explore scientific 14mm 82

32.5mm: LAIDA zoom at 8mm

31mm: LAIDA zoom at 20mm

38.5mm: Morpheus 9mm

34.1mm: SVBony 3-8 zoom special edition for APM binos at 8mm

34.2mm: SVBony 3-8 zoom special edition for APM binos at 3mm"

 

So if I've read this correctly the Svbony 8-20 zoom needs 9 to 10.5mm more intravel compared to a Televue 32mm Plossl.  Looking at the Televue eyepiece specification page at https://www.televue.com/engine/TV3b_page.asp?id=214, this means that it doesn't need quite as much intravel as a 17.3mm Delos.  Most scopes should be able to cope with this.

It's difficult to see from the angle, but the picture on the Svbony website page suggests that the focus position is similar in both 1.25 and 2 inch focusers.  If so, that would be much better than the APM Super Zoom.

What doesn't look too promising for me though is that there's a 1.5mm focus difference from each end of the zoom.  This would mean that it probably wouldn't be parfocal for my old eyes, but may be for younger ones.

Would someone please comment on whether I've got these points right please?

Edited July 15 by Second Time Around

[globular]

14 minutes ago, Second Time Around said:

It's difficult to see from the angle, but the picture on the Svbony website page suggests that the focus position is similar in both 1.25 and 2 inch focusers.

Looks like that to me too.
This picture seems to show that the supplied 2" nosepiece screws fully into the recess in the housing and leaves the 2" shoulder at the same place as the 1.25".

[John]

Well, that's looking a more promising than the APM zoom 🙂

I've had no problems getting the Svbony 3-8mm zoom to focus or the 17.3 Delos come to that, when I owned one of those.

 

 

[LondonNeil]

Bogdan has teased a review coming soon.