ATX/STX rumor (7 Viewers)

[John A Roberts]

From David's link, including the Technical Data sheet. . . .


John


and the official press release is at: https://aa.swarovskioptik.com/press/Greatness_in_the_smallest_detail

 

[John A Roberts]

And the updated BTX Technical Data sheet . . .


John

 

[dipped]

I just got a tape measure out, wow that is a huge chunk of glass for a spotting scope.

First dibs on Kimmo's near perfect 95mm module - he's bound to upscale. I wish...

I wonder if there's a job opening for Birding Sherpas as gear gets progressively bigger and heavier.

 

[dipped]

Oops I measured 150mm out not 115. It's not that huge. But when the 150mm comes out it will be.

 

[quincy88]

And the updated BTX Technical Data sheet . . .
John

Can someone explain why the "effective objective lens diameter" is 110mm?

 

[jring]

Can someone explain why the "effective objective lens diameter" is 110mm?

Well, it seems they have some internal vignetting then for whatever reason and rather state it properly than being pointed out by some eagle eyed reviewer who measures the exit pupil diameter...

Joachim

 

[DRodrigues]

Can someone explain why the "effective objective lens diameter" is 110mm?

It should be an error since only is cited on the BTX info...

 

[DRodrigues]

Hi,

since it has the same magnifications (30-70) and thus focal length (550mm) as the 95mm version, this results into a focal ratio f4.8 - it better should be a triplet at least.

Source link for focal length (thanks Kimmo!): https://www.birdforum.net/showthread.php?t=269099

Joachim

Read some where that the X lens modules have 5 lens, including the 2 of the focusing system.
With this focal ratio the glass used should be better than the one of the X95 - also read some where that the X85 have improved glass compared to the X95 and shows less CA. I hope that the X115 will have less CA, not that I complain much of the X95, after many years using the Optolyth 100...3

 

[henry link]

I expect the 110mm clear aperture is accurate for the BTX. I'm surprised there isn't more vignetting, including with the ATX and STX.

This thing will be hard to pull off properly. They'll certainly need to up their game for color correction. The ED glass will have to one of the types with an Abbe # around 95 and the mating glasses will have to be just right, etc.

Edit: Just saw David's post. I assumed the smaller objective modules were already using the usual fixed triplet and focusing doublet. If they want to keep the same level of spherical correction in the 115 as the 95mm that may need an upgrade, whatever that might mean.

 

[The BulbMogul]

ok been waiting for one of these bad boys ever since rumors were flying around and this will be a great addition to my ATX95.. I will also most likely buy a 2nd eye piece module so can operate to separate systems at once.. Great news and none of the nay sayers or knit pickers will discourage me... I would think this will be a lot easier to get then the NL Pure Bins here in States right off the bat..

 

[DRodrigues]

Eventually a bit more as area of glass increase at a square proportion...
The price eventually would be 1000 euros more expensive than the X95...
...

For someone that didn't had any info from Swarosvki, I was not too far from the specs of the X115...

...
If Swaro would do an astronomical and/or photo version (well I did suggest it to them...), the potential market would also increase...o
In terms of market, Swaro most probably will first improve their eyepiece modules to reply to Harpia...3

I'm curious to see if I will be close also on these...o

 

[Vespobuteo]

The modest price indicates that there will be no fluorite chrystal glass in this beast. Will be tricky to handle the CA in a good way I guess.

 

[Sagittarius]

Looks like Swarovski is trying to push everyone else back with the NL Pure binoculars and now this huge 115mm spotter.
Would love to own both but wish Kowa would bring out their own 115mm or larger spotting scope with Fluorite lens. :t:

 

[The BulbMogul]

Looks like Swarovski is trying to push everyone else back with the NL Pure binoculars and now this huge 115mm spotter.
Would love to own both but wish Kowa would bring out their own 115mm or larger spotting scope with Fluorite lens. :t:

Why a KOWA..? pricing ..?

 

[henry link]

I'd also be more interested in a 115mm Kowa with a Fluorite objective and the adapter for 1.25" eyepieces.

 

[DRodrigues]

I'd also be more interested in a 115mm Kowa with a Fluorite objective and the adapter for 1.25" eyepieces.

If you are wishing, you should wish that it could receive 2" eps...3

I now can use a Nagler 22 on my X95 without vignetting (more hopefully during the weekend...), so the X115 with it should be from another world...:king:

 

[Sagittarius]

Why a KOWA..? pricing ..?

According to everything I've read and heard over the years, the Fluorite lens Kowa produces is superior to any ED Fluoride glass used by the Big 3.

In most reviews, the Big Kowa 88mm Fluorite lens almost always beats the others when compared with them.
That is the main reason I would want a Kowa.
Price has nothing to do with it as a 115mm Kowa would cost a ton of money too.

 

[jring]

Hi,

yes, the BTX prisms vignetting makes sense... so everybody else gets to enjoy the full 115mm...

As for fluorite or ED, that topic has been beaten to death several times over on cloudynights. All things being equal, it can be said that you can build instruments with equally good color correction from fluorite crystal and modern ED glass (the stuff with Abbe numbers beyond 90 - like FPL-53 and 55, FCD 100 or OK4).

For examples, check Table 12 in the following link - number 12 and 14 are typical doublets with FPL-53 (12) and CaF2 (14) - the theoretical polychromatic Strehl values (as determined by the design and assuming a perfect example) in the rightmost column are equal. Same for the triplets in number 17 to 19 where FPL-53 with its ideal partner glass ZKN7 is actually slightly ahead - that is, if you can get a good batch of ZKN7 which is not an easy task.

https://www.telescope-optics.net/semiapo_and_apo_examples.htm

CaF2 being a crystal means that it has no bubbles and thus has a slightly higher transmission - unfortunately the absorption in the glass is not really relevant as compared to the amount of light lost due to reflection despite modern AR coatings...

Since the current Kowa scopes use air spaced doublets, the competition who use mainly triplet objectives should be way ahead, if they were using one or even two modern ED elements in their triplets.
The fact that they aren't does not show their design department in a very favorable light... or their beancounters who did sacrifice modern ED for shareholder value while Kowa sells the most expensive lens material of all for a moderate price...

Joachim

 

[proudpapa56]

My Swaro sales rep brought one in to the shop this afternoon. It's chunky but not as long as I'd thought it would be. My order is in, they should start shipping in Oct. here in the U.S.

 

[John A Roberts]

While the images give some idea of the size of the 115 mm module, a couple of comparisons may be useful in considering performance/ cost tradeoffs . . .

Area of the Objective Glass
The 115 mm/ 4.53” diameter objective, compared to the:
• 65 mm/ 2.56” one, has over three times the area (313%)
• 85 mm/ 3.35” one, has nearly twice the area (83%)
• 95 mm/ 3.74” one, has nearly half more area (46%)

Objective Unit Weight
• While the 95 mm module is 47.3 oz/ 1.34 kg
• The 115 mm module is 74.1 oz/ 2.1 kg,
So the 115 is an extra 27 oz/ 0.76 kg (a 57% increase), though it's only 0.5"/ 13 mm longer

New Backpack
Perhaps in recognition of the larger size and especially the weight of the 115 module, a new Backpack 30 will be available from November
It’s mentioned in the press release at: https://aa.swarovskioptik.com/press/Greatness_in_the_smallest_detail
and the details can be seen at: https://aa.swarovskioptik.com/birding/backpack-c21040518/backpack-p5598805


John