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Can a Non-Fluorite lens binocular compete with a Fluorite lens binocular? (1 Viewer)

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I would like to gather some opinions on this subject. Can a Non-fluorite lens binocular compare optically with a Fluorite lens binocular. Does the arrival of the new Zeiss FL (Fluorite Lens) binoculars signal a change in the binocular market? Will all the other manufacturers follow suite to compete with the new Zeiss or do you think it is just a marketing gimmick to put the word "Fluorite" in your binocular description.

Dennis
 
Just my opinion (i.e., no insider info): I suspect we may see some other brands offering FL, HD or ED glass. If it's helping Zeiss, then at least some of the others will follow suit. OTOH, it's my guess that it won't be Leica or Swarovski that do this, at least not right away (I don't think we'll see an Ultravid APO or EL HD very soon), but rather wannabe brands like Bushnell and Swift.
 
I would like to gather some opinions on this subject. Can a Non-fluorite lens binocular compare optically with a Fluorite lens binocular. Does the arrival of the new Zeiss FL (Fluorite Lens) binoculars signal a change in the binocular market? Will all the other manufacturers follow suite to compete with the new Zeiss or do you think it is just a marketing gimmick to put the word "Fluorite" in your binocular description.

Dennis

Hello Dennis,

I'm sure it is not just a marketing gimmick. May be it is the future, but the present success of the FLs is not really overwhelming (main reason is the use of prisms, which also easily damage the optical performance of a real APO). Leica, Swarovsky and Nikon models proof, that they can stand up against the FLs without using fluorite with no problems. There are no hints, that they will find the use of fluorite being necessary in low power binoculars.
Zeiss has made a new approach to some optical problems, but I wonder if we will see FLs with bigger objective lenses in near future. It seems to be doubtful, if customers are ready to pay the big price for a little less colour.

Walter
 
Walter is pretty much right. It's not a gimmick, but it's also not an improvement that will push the FL past the EL or Ultravid into a different category of quality.

Zeiss made the first flouride glass camera lens in the 70's. Why the sudden use in binoculars? So they can still compete with the Ultravid and the FL?

There is more than one way to look at things.
 
xenophobe said:
Walter is pretty much right. It's not a gimmick, but it's also not an improvement that will push the FL past the EL or Ultravid into a different category of quality.

Zeiss made the first flouride glass camera lens in the 70's. Why the sudden use in binoculars? So they can still compete with the Ultravid and the FL?

There is more than one way to look at things.



In telescopes and spotting scopes APO scopes rule the roost. Takahashi and Astrophysics with their Apochromatic scopes are without a doubt better optically than the achromatic telescopes. Even Swarovski makes an ED Spotting scope which has proven to be superior over non ED lenses. So what your saying is because of the prisms and the low magnification used in binoculars fluorite is not that advantageous. By using fluorite in the objective lens wouldn't that be a considerable improvement in the optics if all other things are equal in the binoculars. I mean if the prisms and eye pieces are of equal quality wouldn't fluorite in the objective improve the view through the binocular.

Dennis
 
In telescopes and spotting scopes APO scopes rule the roost. Takahashi and Astrophysics with their Apochromatic scopes are without a doubt better optically than the achromatic telescopes. Even Swarovski makes an ED Spotting scope which has proven to be superior over non ED lenses. So what your saying is because of the prisms and the low magnification used in binoculars fluorite is not that advantageous. By using fluorite in the objective lens wouldn't that be a considerable improvement in the optics if all other things are equal in the binoculars. I mean if the prisms and eye pieces are of equal quality wouldn't fluorite in the objective improve the view through the binocular.

Dennis


Yes it would improve the view, but it is not a big deal - visual hard to see a difference. APO does not equal APO. The FLs contain glass lenses with some fluoride ions, but no CaF2. So the Zeiss FLs are kind of ED binos. The other top manufacturers use conventional optical glass with similar results - no ED and no fluorite. Only some of their spotting scopes (APO, HD a.s.o.) contain ED lenses - Kowa even uses CaF2. This makes indeed sense, because of their greater magnification. Next step will be (or still is) the use of the new SD glass lenses and we will see very soon, that SD will substitute CaF2 completely also in astronomical APOs.

If somebody is interested in buying a bino for the first time he should also look through a Zeiss FL, but I personally would not give away my 7x42s (Leica Trinovid and Zeiss Dialyt) for a Zeiss FL 7x42.

Walter
 
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SD Lenses?

Wehr said:
Yes it would improve the view, but it is not a big deal - visual hard to see a difference. APO does not equal APO. The FLs contain glass lenses with some fluoride ions, but no CaF2. So the Zeiss FLs are kind of ED binos. The other top manufacturers use conventional optical glass with similar results - no ED and no fluorite. Only some of their spotting scopes (APO, HD a.s.o.) contain ED lenses - Kowa even uses CaF2. This makes indeed sense, because of their greater magnification. Next step will be (or still is) the use of the new SD glass lenses and we will see very soon, that SD will substitute CaF2 completely also in astronomical APOs.

If somebody is interested in buying a bino for the first time he should also look through a Zeiss FL, but I personally would not give away my 7x42s (Leica Trinovid and Zeiss Dialyt) for a Zeiss FL 7x42.

Walter


Walter
What is an SD lens and does it accomplish the same thing as fluorite? Zeiss claims that by using Fluorite Ions in their lenses they accomplish the same thing as a true CaF2 lens or in other words they achieve the same performance without the drawbacks of toxicity and other problems associated with fluorite.
 
denco it seems you misunderstand your FLs a little bit.

The reason they are they brightest out there has little to do with the FL elements but is due to the Abbe/Koenig prisms. The use of FL or even APO is to correct color.

I have heard some rumblings and rumors that because the AK prism design makes the optics very "fast" that without some sort of added color correction the chromatic abberations would be higher than their competitors, as was the case in the Victory/Victory II.

Everything is a compromise. Look at scopes again, to use your example. Longer refractors (slower) have less CA than short tube refractors. Binocular design demands a somewhat short tube design, selt we all be carrying 12" long tubes, so increased abberations are expected. The upside is that the low magnifications we use in binoculars to not make the CA as noticeable, especially in high quality designs with modern coatings.

In short, my opinion is the the FL uses Flourite because without it they could not compete (optics too fast). Also, any HD or FL glass will never be as good as a true APO.
 
In telescopes and spotting scopes APO scopes rule the roost. Takahashi and Astrophysics with their Apochromatic scopes are without a doubt better optically than the achromatic telescopes. Even Swarovski makes an ED Spotting scope which has proven to be superior over non ED lenses. So what your saying is because of the prisms and the low magnification used in binoculars fluorite is not that advantageous. By using fluorite in the objective lens wouldn't that be a considerable improvement in the optics if all other things are equal in the binoculars. I mean if the prisms and eye pieces are of equal quality wouldn't fluorite in the objective improve the view through the binocular.

Dennis

Not all of the lenses in the Zeiss FLs are actually fluoride glass. I'm not sure how many, but I was under the impression that only one or two lenses were FL and the rest, their standard proprietary multicoated ED glass. Not much different than any comptetors, really. I do know flouride lenses can't be used as the exposed obective or ocular lenes, and it's most definitely not used where expense would prohibit. My point, that there's been no real or significant design changes to the form of the binocular other than the inclusion of flouride glass and no vast improvement visually over the rest.

One lens, no matter how advanced isn't going to stretch more out of a design than possible, with most of the high end already about as optimized as they can be. The FL is an improvement, but no, not is not dramatic. I'm sure Leica and Swarovski will follow the trend in due time. They don't need to be in a rush either.

ED Glass was designed as a calcuium fluoride alternative, a low dispersion glass that wasn't fragile, temperature or oxygen sensitive. Fluoride glass has a tendency to shatter in cold weather, and not like prolonged exposure to oxygen. Fluoride glass is a crystal grown in a labratory, ED glass is fabricated through melting/refining/molding.

Also, Zeiss, Leica, Nikon and Canon have both used fluoride glass in their high-end camera lenses for years. They've also used fluoride coated lenses for years. Has it changed the camera world? Neither of these are specific only to Zeiss, and Swarobright ED or Leica HLX ED glass coatings most likely uses some fluoride formulated multicoatings, just not one or two elements of pure fluoride glass.
 
xenophobe said:
Not all of the lenses in the Zeiss FLs are actually fluoride glass. I'm not sure how many, but I was under the impression that only one or two lenses were FL and the rest, their standard proprietary multicoated ED glass. Not much different than any comptetors, really. I do know flouride lenses can't be used as the exposed obective or ocular lenes, and it's most definitely not used where expense would prohibit. My point, that there's been no real or significant design changes to the form of the binocular other than the inclusion of flouride glass and no vast improvement visually over the rest.

One lens, no matter how advanced isn't going to stretch more out of a design than possible, with most of the high end already about as optimized as they can be. The FL is an improvement, but no, not is not dramatic. I'm sure Leica and Swarovski will follow the trend in due time. They don't need to be in a rush either.

ED Glass was designed as a calcuium fluoride alternative, a low dispersion glass that wasn't fragile, temperature or oxygen sensitive. Fluoride glass has a tendency to shatter in cold weather, and not like prolonged exposure to oxygen. Fluoride glass is a crystal grown in a labratory, ED glass is fabricated through melting/refining/molding.

Also, Zeiss, Leica, Nikon and Canon have both used fluoride glass in their high-end camera lenses for years. They've also used fluoride coated lenses for years. Has it changed the camera world? Neither of these are specific only to Zeiss, and Swarobright ED or Leica HLX ED glass coatings most likely uses some fluoride formulated multicoatings, just not one or two elements of pure fluoride glass.



I'm not really an authority on this but I read in some of the Zeiss literature that Zeiss use Fluoride Ions in the objective lens of the FL series. This is supposed to have the benefits of fluoride without the problems of fragility and oxygen exposure problems that pure fluoride has. I feel it is one step closer to a CA free optical system. Probably the next step will be aspherical eyepieces to get rid of the CA in eyepieces like they have done in camera lenses. The question is will people be willing to pay alot of money for maybe not a huge increase in optical quality.
 
I'm not really an authority on this but I read in some of the Zeiss literature that Zeiss use Fluoride Ions in the objective lens of the FL series. This is supposed to have the benefits of fluoride without the problems of fragility and oxygen exposure problems that pure fluoride has. I feel it is one step closer to a CA free optical system. Probably the next step will be aspherical eyepieces to get rid of the CA in eyepieces like they have done in camera lenses. The question is will people be willing to pay alot of money for maybe not a huge increase in optical quality.

Flourite isn't really that delicate. I believe that Takahashi now make 2 element APO scopes, with the outer element made from Flourite, and protected with a hard coating. Obviously if you bring in a cold scope from outside and pour hot water on the objective, it'll shatter. Canon have used Flourite in their long tom lenses for years now, and the only side effect is the need to weather seal the lens. They seem to have had no problems with deterioration of the optics.

As Deco rightly points out, Zeiss use Flouride glass, not Flourite, in the FL range.

I pretty much agree with what Walter has said. The extra Flouride glass element does IMO reduce colour aberrations to a noticeable degree. The extra clarity is probably due to the FL element, and the AK prisms. But most people don't seem to bothered by the CA in competing instruments anyway so IMO the other binoculars on the market can compete. Just look at threads on BF and you will see that many many people prefer Leica Ultravids, or Swarovski ELs, or Nikon HGLs, and the real connoiseurs opt for the Goldrings (humour intended in that last bit).

The problem is that if you improve the objectives, then you have to either increase the price, or reduce costs elsewhere. I am not convinced that Leica and others will respond in kind, though I would be pleased if they did. I don't see them introducing two lines e.g. Ultravid and Ultravid ED, as it would suggest that the vanilla Ultravid was lacking. But who knows. I guess it all depends on how we consumers respond to the Zeiss FL. If we all buy Zeiss, and wave goodbye to Leica et al, then yes they will respond in kind. The Zeiss FL seems to be doing very well, but it is not wiping the floor with the competition, assuming that the recent BF survey is indicative of the market place.

The other elements in the Zeiss FL are normal non-ED glass i.e. a crown and a flint. ED means extra low dispersion, and according to Alan French ED is the widely used generic term for extra-low dispersion glass, though Nikon also use the term in their marketing literature, and as part of the lens name. Other manufacturers use other terms. I think SD means super low dispersion (same thing), and HD, LD and APO are in effect all used to indicate the use of ED glass, or equivalent e.g. Flourite. Does it make a difference? Yes, it does improve the overall image quality. I have a Nikon 200mm AIS F4 micro lens. It is non-ED, and gives nice image quality, but it's not quite as good as the best ED lenses, such as the Nikon AF equivalent.

Leif
 
xenophobe said:
Not all of the lenses in the Zeiss FLs are actually fluoride glass. I'm not sure how many, but I was under the impression that only one or two lenses were FL and the rest, their standard proprietary multicoated ED glass. Not much different than any comptetors, really. I do know flouride lenses can't be used as the exposed obective or ocular lenes, and it's most definitely not used where expense would prohibit. My point, that there's been no real or significant design changes to the form of the binocular other than the inclusion of flouride glass and no vast improvement visually over the rest.

One lens, no matter how advanced isn't going to stretch more out of a design than possible, with most of the high end already about as optimized as they can be. The FL is an improvement, but no, not is not dramatic. I'm sure Leica and Swarovski will follow the trend in due time. They don't need to be in a rush either.

ED Glass was designed as a calcuium fluoride alternative, a low dispersion glass that wasn't fragile, temperature or oxygen sensitive. Fluoride glass has a tendency to shatter in cold weather, and not like prolonged exposure to oxygen. Fluoride glass is a crystal grown in a labratory, ED glass is fabricated through melting/refining/molding.

Also, Zeiss, Leica, Nikon and Canon have both used fluoride glass in their high-end camera lenses for years. They've also used fluoride coated lenses for years. Has it changed the camera world? Neither of these are specific only to Zeiss, and Swarobright ED or Leica HLX ED glass coatings most likely uses some fluoride formulated multicoatings, just not one or two elements of pure fluoride glass.

Only one element in the Zeiss FL objective group is made from Flouride glass. The rest are 'bog standard' glass i.e. high quality non-ED glass.

Canon use Flourite elements in camera lenses, but Nikon use ED glass instead. I've no idea what Zeiss and Leica use.

I think you are confusing Flouride glass and Flourite. Flouride glass is glass with Flouride ions, whereas Flourite is CaFl. As you say, it is grown in the factory. Flourite doesn't really have a tendency to shatter in cold weather, though it seems to have gained that reputation.

Leif
 
Yes, I did confuse the CaF and Fluoride glass. Either way the inclusion of fluroide glass in the Victory FL line isn't the end-all of binocular quality or clarity.

The CaF glass is subject to moisture absorbtion and would need to be heavily coated.
 
xenophobe said:
[SNIP]
One lens, no matter how advanced isn't going to stretch more out of a design than possible, with most of the high end already about as optimized as they can be. The FL is an improvement, but no, not is not dramatic. I'm sure Leica and Swarovski will follow the trend in due time. They don't need to be in a rush either.
[SNIP]

In low power binoculars, you may be right, but ED (extra-low dispersion) glass has allowed a major improvement in very hight end optics designed for astronomers. Virtually all combinations of normal glasses leave the red and blue ends of the spectrum out of focus, which detracts from high power viewing. The abnormal dispersion characteristics of ED glass (either true fluorite or fluor-crowns such as FPL-53) allow, with the choice of the proper matching normal glass or glasses, major improvements in color correction. Some high end APOs show virtually no secondary color at any magnification. (You can't do that with normal glasses - at least if you want a design that is not of very long focus or very small aperture, or want to make something like a Schupmann, which uses two elements of the same glass.)

Any design that features improved color correction includes an ED element. The marketing folks like to set themselves apart from other companies by making up their own designations - HD (high definition), UD (ultra-low dispersion), SD (special dispersion) - but they are all using essentially the same stuff.

Clear skies, Alan
 
Sure, you will be able to advance color correction technology in devices, but you won't gain brightness or clarity (unless you consider CA to be detrimental to clarity, which could be a justifiable arguement) by replacing the composition of one lens, which is really the point I've been trying to get across.

I'm also not talking about devices with high magnification or long focal lengths which the use of apochromatic glass is definitely justifiable, if not a real requirement.
 
Back to the basic question. Despite the above arguements for ED glass of any type, I do still maintain that a non-ED binocular can compete in today's market. In the total package that is a binocular, the best is the one taken with, as fancy glass does no good left at home.
 
Robert Ellis said:
Back to the basic question. Despite the above arguements for ED glass of any type, I do still maintain that a non-ED binocular can compete in today's market. In the total package that is a binocular, the best is the one taken with, as fancy glass does no good left at home.

You are right. But furthermore, the premise upon which this thread was started is flawed. denco's assumptions, stated clearly and repeatedly in several threads, are nothing more than opinion grounded in brand bias. I have compared Ultravid and FL 7x42s side-by-side for an extended period of time on two occasions and reached the same conclusion each time: in the field I am unable to distinguish between their images. The FL in very high contrast situations exhibits a hint of CA, no matter how much anybody denies its presence. Under the same conditions I observe either the same or only a trace more in the Ultravid. The only difference is that the Ultravid requires slightly better positioning over the eyes--the FL is a bit more forgiving. Both binoculars provide the same brightness, sharpness, and contrast, though the Ultravid has a slightly larger "sweet spot." Ergonomics are an entirely different matter. I can't stand the handling and what I consider the slightly "cheap" feel of the FL, though others may love it. Leica's great achievement has been made through improved coatings, while Zeiss' has been made with glass. Both are great binoculars, and in actual use in the field both will provide astounding views of birds. As you say, that is what we use these things for, isn't it?
 
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xenophobe said:
Sure, you will be able to advance color correction technology in devices, but you won't gain brightness or clarity (unless you consider CA to be detrimental to clarity, which could be a justifiable arguement) by replacing the composition of one lens, which is really the point I've been trying to get across.

I'm also not talking about devices with high magnification or long focal lengths which the use of apochromatic glass is definitely justifiable, if not a real requirement.

I did a poor job of making my point. You seemed to denigrate ED material.

The availablility of ED glass with abnormal dispersions is a very big deal and extremely important in some applications. The reduction of secondary and lateral color, especially at high magnifications, does increase clarity and the ability to see fine, low contrast details. I think the question of how much difference it makes in low power optics is still open, but it sure makes a diffference in spotting scopes used at 60x, astronomical telescopes, and telephoto lenses.

Clear skies, Alan
 
I think flourite lenses in binoculars to a certain level is a gimmick. In the most cases you don't notice any false colours in binoculars at normal handholdable magnifications.
The big gain of flourite lenses is absolutely when using higher powers, I don't think there exist any achromatic 60mm spottingscope without clearly noticable false colours at 50x. But there are good 60mm astronomical apochromatic shortscopes who produce colorfree and sharp images at magnifications who are compeletely unusable with a achromatic one.
 
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