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Kowa 55A/55S (2 Viewers)

It is great news. Following is the kink to the KOWA site. It mentioned the specs as well.

TSN-55-PROMINAR

According to it, the weight of the scope has increased compared to the previous model. The price has also increased significantly reaching the price of Swarovski ATC/STC. I am looking forward to seeing a detailed comparison of the Kowa with the Swaro soon.
 
This scope is clearly aimed at the Swarovski STC/ATC. It's going to be interesting to read the first reports and reviews when it hits the market.

A couple of observations based on the images and the specifications:
  • The Kowa appears to have a properly sized tripod foot. That's a good thing.
  • An interesting question is how well it's going to be balanced with that huge eyepiece.
  • The scope is pretty short. I wonder what the focal length is. I hope it's not too short, resulting in a very fast objective with all the problems that entails.
  • At the same time it's pretty heavy for a small scope. I wonder whether it wouldn't have been better to offer it with two wide angle eyepieces (24/25x+40x) to keep the weight down.
Hermann
 
The scope is pretty short. I wonder what the focal length is. I hope it's not too short, resulting in a very fast objective with all the problems that entails.
The magnification range of the TE-11WZ would make that about 330-340 mm so around f/6, faster than the 66 but still slower than 88 and 99.
At the same time it's pretty heavy for a small scope. I wonder whether it wouldn't have been better to offer it with two wide angle eyepieces (24/25x+40x) to keep the weight down.
Agree on that, but Kowa don't have any eyepieces which would fulfil that requirement. The TE-11WZ is very good though.

John
 
Too bad the eyepiece is fixed, so no other eyepieces or the extender can be use with the new scope.

Initially I thought the 55A must use the same fixed objective triplet, focusing doublet and Schmidt erecting prism that the larger current TSN angled scopes use, but the peeks we get of the optics in one of the videos shows an objective and prism design very much like the old TSN-553 the new scope replaces. A Porro with a moving prism for focusing is followed by a semi-pentaprism for angling the light path to the eyepiece by 45º. The objective group is not shown well enough to be certain of its design, but it certainly could use the same air spaced doublet as the 553. A count of the reflections returning from the front lenses would settle that question.
 
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Hi,

since the 553 was not known for showing excessive CA, there was probably no need to make it even heavier by including a triplet objective. The Schmidt prism vs the porro pair and semi pentaprism would have saved weight though. So maybe fluorite doublet plus Schmidt prism would have been optimal...

But it seems they addressed the weak point of the 553 in the form of the old EP and put the current wide angle zoom on it... might be a nice instrument...

Joachim
 
This scope is clearly aimed at the Swarovski STC/ATC. It's going to be interesting to read the first reports and reviews when it hits the market. [...]
  • At the same time it's pretty heavy for a small scope. [...]
Not really, at least not in comparison with its Swarovski contender: ATC: 970g - 55A: 965g (all as advertised).
Those two are a perfect couple to choose from depending on ones own preferences (e.g. barrel vs. dual focus). Optically I would expect them to be close.
Werner
 
Not really, at least not in comparison with its Swarovski contender: ATC: 970g - 55A: 965g (all as advertised).
Well, IMO the STC/ATC are also pretty heavy for a small scope. Unnecessarily heavy IMO because of their huge zooms.

Hermann
 
Well, IMO the STC/ATC are also pretty heavy for a small scope. Unnecessarily heavy IMO because of their huge zooms.

Hermann
I know what you mean: Your baseline seems to be the ED50. But, IMO, that is an exceptional light (and a bit fragile sometimes) specimen and hard to beat in that weight respect. However, I daresay the ED50 is not the contender of either 55A or ATC.
Werner
 
Hi,

since the 553 was not known for showing excessive CA, there was probably no need to make it even heavier by including a triplet objective. The Schmidt prism vs the porro pair and semi pentaprism would have saved weight though. So maybe fluorite doublet plus Schmidt prism would have been optimal...

But it seems they addressed the weak point of the 553 in the form of the old EP and put the current wide angle zoom on it... might be a nice instrument...

Joachim
Really??? The one thing I love about my 553 is what I perceive as complete lack of CA! Are we talking about the same model or did I miss it somehow?
 
Your baseline seems to be the ED50. But, IMO, that is an exceptional light (and a bit fragile sometimes) specimen and hard to beat in that weight respect.
The ED50 is not really my baseline. I used several small and light scopes over the years, and I know the weaknesses of the ED50 all too well. But I still think it should be possible to build a small travel scope with a weight below ~800 gr. Swarovski and Kowa had the chance to do so, and they failed, IMO because they didn't understand the importance of weight and decided to use an existing (and heavy!) zoom eyepiece for their travel scopes. A zoom eyepiece that was originally designed for larger scopes.
However, I daresay the ED50 is not the contender of either 55A or ATC.
No, it isn't. It's in an entirely different weight class. And in an entirely different price range.

Hermann
 
[...] But I still think it should be possible to build a small travel scope with a weight below ~800 gr. Swarovski and Kowa had the chance to do so, and they failed, IMO because they didn't understand the importance of weight and decided to use an existing (and heavy!) zoom eyepiece for their travel scopes. A zoom eyepiece that was originally designed for larger scopes. [...]
I do not disagree with you in terms of the advantage of having a scope as much light as possible. You suggested a limit around 800 g. Fun fact: My TSN-554 is advertised with 800 g. So what? A few grams too much?
On the other hand, I see it as an advantage having the same zoom eyepiece as, in my case, on the TSN-883 and would bear the additional weight in exchange for its optical benefits.
This discussion again shows how personal preferences differ and driving (buying) decisions. There is no right or wrong, IMO. Neither with us nor with Swarovski or Kowa.
Werner
 
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Good comparison with the Swaro ATC:
Interesting comparison. Not sure if I'd trust all of that guy's observations, I'd have to compare both scopes in the field myself. Still, it's a nice video. BTW, the most interesting part to me was closeup of the tripod feet. Kowa got that right it seems, Swarovski didn't.

And Swarovski appears to have cheated a bit on the weight.

Hermann
 
Interesting comparison. Not sure if I'd trust all of that guy's observations, I'd have to compare both scopes in the field myself. Still, it's a nice video. BTW, the most interesting part to me was closeup of the tripod feet. Kowa got that right it seems, Swarovski didn't.

And Swarovski appears to have cheated a bit on the weight.

Hermann

There is another important point he did not mention....if you get a scope this size, the priority is portability. These scopes give you the option to avoid having to carry a tripod and use, for example, a bean bag instead (not the same experience, still usable). Focus adjustment in the barrel is much less convenient with a bean bag.

I actually like his reviews. I watched a good few of them and find him objective and balanced.
 

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