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Nikon WX testing

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#51 edwincjones

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Posted 10 June 2017 - 06:10 PM

well-maybe I am just too old school to understand,

but 7x50 and 10x50s are handheld binoculars,

these are too heavy to handhold-at least for long.

 

time will tell

 

edj


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#52 karstenkoch

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Posted 10 June 2017 - 09:06 PM

No doubt the WX's unique attributes will show up in more affordable versions from other manufacturers before long....cool.gif


Yep, here comes the onslaught of rebranded UWA binocular copies. At some point they will get good enough and cheap enough and then I'll buy a pair. Probably won't ever test as well as the subject Nikon however (just to segue back to the topic). Hey, this is a good thing! Just when you thought the industry was stagnating ... real binocular innovation!
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#53 Mr. Bill

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Posted 10 June 2017 - 09:47 PM

 

No doubt the WX's unique attributes will show up in more affordable versions from other manufacturers before long....cool.gif


Yep, here comes the onslaught of rebranded UWA binocular copies. At some point they will get good enough and cheap enough and then I'll buy a pair. Probably won't ever test as well as the subject Nikon however (just to segue back to the topic). Hey, this is a good thing! Just when you thought the industry was stagnating ... real binocular innovation!

 

My point exactly....



#54 Sgt

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Posted 11 June 2017 - 04:57 AM

I have mixed feelings about that.  I'd love to see a cheaper version that would be more accessible to the masses (including me!) but then I hate the idea of Chinese copies ignoring any patents, taking advantage of the Nikon without doing any of their own engineering or research and development apart from reverse engineering the WX.  Goes against my sense of fairness.  For me the ideal would be if Nikon themselves released a 'lite' version, perhaps with cheaper materials, slightly cheaper coatings, more automated manufacturing that differentiates itself from the WX but still with same/similar specs.   

 

Speaking of 'lite' I wonder if optical plastics exist which would allow for this sort of binocular at a much lighter weight?  


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#55 CAAD9

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Posted 11 June 2017 - 05:42 AM

Even if you put fairness aside just for argument's sake: irrespective of their origins the real danger posed by cloners is that they are a real threat to innovation and progress.  

 

I get the attraction of low cost copies, I'm not made of $ myself. Nevertheless there is a certain self defeating quality about them all...

 

But I'm not going to worry about any of that here.  

 

I'm just going to enjoy this technical wonder for what it is, even if only vicariously.  Happy days!



#56 Mad Matt

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Posted 11 June 2017 - 05:49 AM

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.
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#57 edwincjones

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Posted 11 June 2017 - 06:23 AM

question.gif

 

 

Have all the clones hurt Fujinon?  I doubt it but they have  allowed many to enjoy the secondary optics.

Fuji sales may be less but the brand name binos are still available for those who want them.

 

$6400 is out of the reach of most observers, even a street price several thousand dollars less is still out of reach.

If the WX is cloned, it will become available to many more, who will happily accept the lower price and  quality(?).

 

edj


Edited by edwincjones, 11 June 2017 - 06:27 AM.


#58 Jon Isaacs

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Posted 11 June 2017 - 08:15 AM

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.

 

Is there really anything in these binoculars that is revolutionary, that represents something more than existing technologies taken to the extreme?  It seems to me that a skilled design team could develop binoculars like these without knowledge of the optics, just the specs:

 

10 x 50s with a flat, 9 degree TFoV.. 

 

:shrug:

 

Jon


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#59 jrbarnett

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Posted 11 June 2017 - 08:57 AM

Longitudinal chromatic aberration is invisible. A good quality 4X10 bino placed behind the eyepiece, thus acting as a 4X quadrupler, shows a still mighty fine image! The resolving power far surpasses the eye's ability to resolve. At this 40X on the 10X bino, details on a moderately distant power pole and its hardware were revealed which I think could hold up reasonably well compared to a dedicated 40X50 spotting scope of middling quality.

 

There is lateral chromatic aberration, which I suspect is introduced by the eyepiece. At the field edge, where it's naturally of maximal magnitude, I estimated the angular width of the colored fringes on a distant power pole as seen against the brighter sky. When the pole is placed near the right side field edge, there is a purple fringe seen against the right side of the pole, and a green fringe seen adjacent to the left side of the pole, projected against the sky. These two fringes are of essentially equal width. The pole was measured to be some 400m distant, using a laser rangefinder. It's apparent angular width I estimate to be some 2 arcminutes. The colored fringes for the 10X bino were about 1/4 the pole width, or about 1/2 arcminute. At 10X this is a magnified apparent width of 5 arcminutes. I did a quicker examination of this for the 7X50, and find a roughly similar magnified apparent colored fringe width of some 5 arcminutes. And so the *apparent* extent of this fringing is about the same for both binos at each's field edge, in spite of the smaller AFoV for the 7X unit. Note that these are *estimates*, which certainly could be improved upon.

 

Field flatness is excellent. Even for my increasingly crystalizing eye lenses wink.gif , for which focus accommodation is poor, it required no refocusing whatsoever to retain best sharpness as I scanned across the full field.

 

No astigmatism of note was seen even to the field edge. But if I go back tomorrow we'll be using an artificial star as seen across the building's basement. In such darkness I'll be using the full aperture due to my dilated irises. I just hope the near focus accommodates this...

 

I had no trouble at all seeing both fields in their entirety. But then, I also do well with 100 degree AFoV oculars in bino mode.

 

Late afternoon car headlights did not reveal any roof line-induced diffraction spike. I plan to use a blazing LED flashlight in the darkened basement to make for a *much* more extreme test.

 

The daytime impressions, using high and low contrast test subjects, were most positive indeed. Based on this, I feel confident that nighttime performance will not disappoint. But it sure would be nice to have had that opportunity!

 

Hopefully more to come tomorrow...

Thanks Glenn.

 

Nice thorough-as-possible-under-the-test-circumstances report from a knowledgeable  bino-guru.  I'm left with the impression that these, while beautifully made and thoughtfully designed, are priced for perfection, but do not quite achieve grace.  :grin:

 

You've satisfied 100% of whatever small curiosity I may ever have had regarding the WXs, and even with mad money these would not be a splurge I'd entertain.

 

That said, I am going to give the comparatively flawed, compromised, Nikon 18x70s (my idea of a mad-money splurge at $1050 direct from the Land of the Rising Sun).

 

Best,

 

Jim



#60 jrbarnett

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Posted 11 June 2017 - 09:16 AM

 

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.

 

Is there really anything in these binoculars that is revolutionary, that represents something more than existing technologies taken to the extreme?  It seems to me that a skilled design team could develop binoculars like these without knowledge of the optics, just the specs:

 

10 x 50s with a flat, 9 degree TFoV.. 

 

shrug.gif

 

Jon

 

Do we have any cut-aways of the Docter 12.5 UWAs?  Hard to say whether there are any clones, or if so, who is cloning who, without knowing what's inside each of the various designs.  Certainly the Chinese are capable of making excellent 80+ degree eyepieces; sometimes cloned designs and sometimes novel designs.  I don't find the 12.5mm UWA to be particularly special in any regard other than weight for its volume, largely due to the poor choice of machined stainless steel for the lower assembly.

 

The reason we won't see Chinese clones of or competitors to these is that the market is too small for the margins they'd likely achieve.  Consider, 100-degree Chinese eyepieces (Ethos clones) run about $450 street price, and are sometimes discounted.  Let's say the manufacturer cost is 50% of the street price (probably higher than that, but for argument's sake let's assume).  That's $225 (2x) or $450 for the eyepieces alone.  To match the specs and comparable levels of correction, they'd need the fancy prism design and the complex objectives.  Turning to the objective end, figure that the objectives would not be more than the objectives in their 80mm FCD100 triplets.  The scope retails for $999.  Assume 40% margins again, leaving manufacturer cost at $500.  Let's speculate that the cost of the optics is about 50% of the total cost, so again $250 (2x) or $500 for a pair of 50mm FCD100 fancy objectives.  Then there's the magic prisms.  I have no idea, but let's say they're at least as costly as the eyepieces and objectives, so another $950 for the prism sets, plus the rest of the structure.  So if the cost to ES would be ~$1900 to manufacture a credible implementation of the spects, and they'd like at least 40% margins, they would need to retail these for over $3000.  Do you see many takers for $3000 Chinese 50mm binoculars of *any* specs?  I don't.  Heck, the market for $3000 astronomy binoculars of any aperture is pretty small.

 

The Chinese are most effective economically where there's at least modest and preferable higher volume.

 

Best,

 

Jim


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#61 jrbarnett

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Posted 11 June 2017 - 09:25 AM

question.gif

 

 

Have all the clones hurt Fujinon?  I doubt it but they have  allowed many to enjoy the secondary optics.

Fuji sales may be less but the brand name binos are still available for those who want them.

 

$6400 is out of the reach of most observers, even a street price several thousand dollars less is still out of reach.

If the WX is cloned, it will become available to many more, who will happily accept the lower price and  quality(?).

 

edj

I agree on the price being out of reach for many prospective buyers, but even for buyers with the scratch to dump $6k+ into the hobby (there are many) I don't see many of them choosing to put $6k into a pair of 50mm binoculars.  There are many ways to enjoy the night sky, and $6k can buy you a limitless number of different experiences. The experience of an extra few degrees of FOV in a well-corrected 50mm binocular, while novel, is quite nuanced compared the experience through alternatives (i.e., top line Nikon or Fuji 7x50s and 10x50s); putting $6k into a premium 16" Dob, on the other hand, is not a nuanced difference at all.  It is different (not necessarily "better" in every respect) by many orders of magnitude.

 

Put another way, for the price of the WXs you could buy Nikon Prostars and a 14" Premium Dob for the same investment, buying new.  Most amateurs with that kind of budget and no fancy binoculars or fancy Dob would opt for the combo meal rather than the appetizer made with genuine gold leaf.  :grin:  

 

Regards,

 

Jim 


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#62 range88

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Posted 11 June 2017 - 09:40 AM

 

 

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.

 

Is there really anything in these binoculars that is revolutionary, that represents something more than existing technologies taken to the extreme?  It seems to me that a skilled design team could develop binoculars like these without knowledge of the optics, just the specs:

 

10 x 50s with a flat, 9 degree TFoV.. 

 

shrug.gif

 

Jon

 

Do we have any cut-aways of the Docter 12.5 UWAs?  Hard to say whether there are any clones, or if so, who is cloning who, without knowing what's inside each of the various designs.  Certainly the Chinese are capable of making excellent 80+ degree eyepieces; sometimes cloned designs and sometimes novel designs.  I don't find the 12.5mm UWA to be particularly special in any regard other than weight for its volume, largely due to the poor choice of machined stainless steel for the lower assembly.

 

The reason we won't see Chinese clones of or competitors to these is that the market is too small for the margins they'd likely achieve.  Consider, 100-degree Chinese eyepieces (Ethos clones) run about $450 street price, and are sometimes discounted.  Let's say the manufacturer cost is 50% of the street price (probably higher than that, but for argument's sake let's assume).  That's $225 (2x) or $450 for the eyepieces alone.  To match the specs and comparable levels of correction, they'd need the fancy prism design and the complex objectives.  Turning to the objective end, figure that the objectives would not be more than the objectives in their 80mm FCD100 triplets.  The scope retails for $999.  Assume 40% margins again, leaving manufacturer cost at $500.  Let's speculate that the cost of the optics is about 50% of the total cost, so again $250 (2x) or $500 for a pair of 50mm FCD100 fancy objectives.  Then there's the magic prisms.  I have no idea, but let's say they're at least as costly as the eyepieces and objectives, so another $950 for the prism sets, plus the rest of the structure.  So if the cost to ES would be ~$1900 to manufacture a credible implementation of the spects, and they'd like at least 40% margins, they would need to retail these for over $3000.  Do you see many takers for $3000 Chinese 50mm binoculars of *any* specs?  I don't.  Heck, the market for $3000 astronomy binoculars of any aperture is pretty small.

 

The Chinese are most effective economically where there's at least modest and preferable higher volume.

 

Best,

 

Jim

 

You over-estimated the cost by far.

Cut everything in half and it's closer to reality.

For example, the Chinese Ethos clones are sold for less than $225 here, actually pay ¥1000 you can take one home, that's less than $150.



#63 Mr. Bill

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Posted 11 June 2017 - 10:10 AM

question.gif

 

 

Have all the clones hurt Fujinon?  I doubt it but they have  allowed many to enjoy the secondary optics.

Fuji sales may be less but the brand name binos are still available for those who want them.

 

$6400 is out of the reach of most observers, even a street price several thousand dollars less is still out of reach.

If the WX is cloned, it will become available to many more, who will happily accept the lower price and  quality(?).

 

edj

In the meantime, I'll just "limp along" with my Fuji 10x50s....wink.gif


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#64 Jon Isaacs

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Posted 11 June 2017 - 10:19 AM

You over-estimated the cost by far.
Cut everything in half and it's closer to reality.
For example, the Chinese Ethos clones are sold for less than $225 here, actually pay ¥1000 you can take one home, that's less than $150.

 

 

The Explore Scientific 100 degree eyepieces seem to be close to a Ethos clone,  the others,  probably not.  Can you buy a ES 100 degree for $150 US? 

 

Jon



#65 tropical

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Posted 11 June 2017 - 10:23 AM

I'd never buy any ES eyepieces when in my conscious mind knowing these are in violation of copyright.  Same principle applies to binoculars.  I just say no to Lunt/APM ... even the person behind it is a German.



#66 Mr. Bill

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Posted 11 June 2017 - 10:50 AM

This 85 degree fov in the XM doesn't hold much appeal to my eyes....I find that 65-70 degrees for binocular viewing to be most comfortable. I've tried both the 12.5 Doctor and 13mm Nagler eps and prefer the DeLites; it just suits my eyes better.

 

OTOH, I find the 80-100 degree fov in my Naglers and Ethos eps to be most enjoyable for cyclops viewing.


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#67 range88

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Posted 11 June 2017 - 10:51 AM

 

You over-estimated the cost by far.
Cut everything in half and it's closer to reality.
For example, the Chinese Ethos clones are sold for less than $225 here, actually pay ¥1000 you can take one home, that's less than $150.

 

 

The Explore Scientific 100 degree eyepieces seem to be close to a Ethos clone,  the others,  probably not.  Can you buy a ES 100 degree for $150 US? 

 

Jon

 

 

 

You over-estimated the cost by far.
Cut everything in half and it's closer to reality.
For example, the Chinese Ethos clones are sold for less than $225 here, actually pay ¥1000 you can take one home, that's less than $150.

 

 

The Explore Scientific 100 degree eyepieces seem to be close to a Ethos clone,  the others,  probably not.  Can you buy a ES 100 degree for $150 US? 

 

Jon

 

The United Optics XWA clones(I don't know who rebranded them,maybe APM? but someone has.PS I noted they are called Lunt Engineering HDC)  are solid 100° performers and at least on a par with the ES, if not better. And they are sold for that much.


Edited by range88, 11 June 2017 - 10:56 AM.


#68 Foss

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Posted 11 June 2017 - 10:57 AM

Thank you Glen for going above and beyond the call of duty. Nikon ought to gift you a set (of your choosing) for your work.


Edited by Foss, 11 June 2017 - 10:58 AM.

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#69 Mad Matt

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Posted 11 June 2017 - 10:59 AM

 

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.


Is there really anything in these binoculars that is revolutionary, that represents something more than existing technologies taken to the extreme? It seems to me that a skilled design team could develop binoculars like these without knowledge of the optics, just the specs:

10 x 50s with a flat, 9 degree TFoV..

shrug.gif

Jon

Look carefully at the fourth element (ignoring the prisms) in the cut away picture on Holger's website: http://www.holgermer...x/nikon_wx.html

The front surface of that element has two curves!!!

It is concave on the inner 1/2 and convex on the outer! I have never seen a lens like that used in any optical device... and I can only speculate that, that little piece of glass is exceptionally hard to make. Looks pretty ground breaking to me but then I am somewhat of any optics geek

 

EDIT: Error in my judgment. Nothing unusual about the corrector


Edited by Mad Matt, 12 June 2017 - 04:49 AM.


#70 range88

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Posted 11 June 2017 - 11:12 AM

 

 

I would not be worried about clones so much... looking at the cutaway views on Holger's website I strongly suspect the rear corrector to require very high tolerances in both the curvatures as also the mechanical placement. I suspect this is also the reason they are not internally focused.

I have yet to see any Chinese clones of the Docter Aspectem or the 12,5 UWA eyepieces and I suspect that manufacturing tolerances is the reason.


Is there really anything in these binoculars that is revolutionary, that represents something more than existing technologies taken to the extreme? It seems to me that a skilled design team could develop binoculars like these without knowledge of the optics, just the specs:

10 x 50s with a flat, 9 degree TFoV..

shrug.gif

Jon

Look carefully at the fourth element (ignoring the prisms) in the cut away picture on Holger's website: http://www.holgermer...x/nikon_wx.html

The front surface of that element has two curves!!!

It is concave on the inner 1/2 and convex on the outer! I have never seen a lens like that used in any optical device... and I can only speculate that, that little piece of glass is exceptionally hard to make. Looks pretty ground breaking to me but then I am somewhat of any optics geek

 

The fouth element from the objective is the first lens/group of a field flattener,which maybe of a 2+1 configuration.

I don't find anything unusual...Can you be more specific?



#71 Mad Matt

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Posted 11 June 2017 - 11:26 AM

Look at the inner surfaces where the two elements of the field flattener touch each other. Isn't the air gap in the middle very unusual?

 

EDIT: The corrector is not unusual, error in my judgment. 


Edited by Mad Matt, 12 June 2017 - 04:50 AM.


#72 range88

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Posted 11 June 2017 - 11:53 AM

Look at the inner surfaces where the two elements of the field flattener touch each other. Isn't the air gap in the middle very unusual?

I still don't catch your point. I think they are perfectly normal.

One with a concave surface and the other with a convex.



#73 Mr. Bill

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Posted 11 June 2017 - 11:54 AM

This is exciting stuff.....impressive optical train and apparently groundbreaking. Nikon has upped the ante. 

 

Whether it's worth $6K is beside the point.....we'll see benefits from this in other products soon.

 

waytogo.gif



#74 Henry Link

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Posted 11 June 2017 - 01:48 PM

Look at the inner surfaces where the two elements of the field flattener touch each other. Isn't the air gap in the middle very unusual?

I think the cutaway leaves something to be desired as an accurate representation. My reading is that the virtual "slicing" of the binocular is a bit off-center so that the small group of lenses just behind the prisms show about 70% of their full diameters at the slice. If they were virtually sliced at 50% I'm pretty sure the opposing concave surfaces would meet at the lens edges.

 

 

Other problems with the cutaway are that it doesn't show cemented doublets or make clear whether the small negative group moves with the eyepiece lenses or remains stationary. I imagine there are probably four cemented doublets: the front lens of the objective, probably the first lens of the small negative group and the two thick lenses in the basic eyepiece group. BTW, if the field and eye lenses of that group are cemented doublets then it very closely resembles the Kohler eyepiece used in the Zeiss Oberkochen 8x30 W over 60 years ago. In fact, the design of this binocular looks more like a culmination of decades of binocular design evolution rather than a revolutionary innovation.


Henry


Edited by Henry Link, 11 June 2017 - 02:06 PM.


#75 Mad Matt

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Posted 11 June 2017 - 02:02 PM

 

Look at the inner surfaces where the two elements of the field flattener touch each other. Isn't the air gap in the middle very unusual?

I still don't catch your point. I think they are perfectly normal.

One with a concave surface and the other with a convex.

 

Ok, A picture is worth a thousand words.

 

Here is a close up of the corrector elements. It assumes the corrector has 2 elements and shows only one possible configuration. In this example, the first surface of the last element has a surface with both a convex and concave zones. of course it could also be the other way around. Assuming nearly the full aperture of the last element is used, there has to be at least one very complex surface. I have never seen something like that before but that does not mean it does not exists. Of course if only the mid concave part is in the optical path then it is not as critical. 

 

If you think Aspheric's are complex then I would guess this is off the chart grin.gif

 

[EDIT: As noted by others in this thread, the cut way is not centered on the lens which gives the impression that the elements have an unusual shape.  I did not catch that and was obviously misled. I removed the picture as I do not have the rights to it and I was completely way off in left field blush.gif crazy.gif 

 

It looks to be corrector of normal design... nothing to see here, keep moving along please smile.gifwink.gif  ]


Edited by Mad Matt, 12 June 2017 - 04:51 AM.

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