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Any special glass (ED, fluoride, etc) used in CL series? (1 Viewer)

moyang_mm

Member
Hello everyone,

First time poster here. I am currently looking for my first binocular. I've done some research on the internet and now I am deciding between the CL companion 8x30 and the EL 8x32. In camera lenses usually the number of special glass elements used is an indicator of the optical quality (although it is not a rule). For example, high-end lenses typically use low-dispersion elements (ED, UD, SLD, fluorite, etc) and aspherical element to correct various types of aberration. I wonder if this true for binoculars. I've carefully read through Swarovski website, but I didn't find any information regarding the optical formula used for CL series binoculars. The EL does have so-called "HD optics", which contains fluoride. I guess those fluoride-containing glass could achieve something similar to fluorite (CaF2). But I am not sure if CL has something similar as well. Should I worry about the optical quality of CL, if it doesn't have any special glass? I am a bit hesitant of dropping $2200 on the EL;)

Any advice will be greatly appreciated.
 

Binastro

Well-known member
Hi and welcome.

Camera lenses are a lot more complex than binocular optics.
They often cover wide angles.
The use of special glasses and aspherics usually is to reduce the number of lens elements to sensible levels.
Zoom lenses may have 18 elements, even with special glass elements. Some broadcast lenses have 30 elements.
Some camera lens raw glass costs more than gold.
The camera lenses are often much faster optics than binocular optics.

I wouldn't worry about special glass in binoculars too much it depends on the optical reputation of the binocular.
Aspherics have been described to me as a bl..dy nuisance by a top designer.

I don't think that any binoculars contain fluorite crystal, except maybe the Takahashi 22x60.

B.
 

[email protected]

Well-known member
Supporter
I once asked Swarovski if they use HD glass in their CL series binocular because it is not specified anywhere in their specification's and they said the CL line uses very high quality glass but they didn't use HD in their wording. As Binastro says above the quality of glass depends on the manufacturer and Swarovski is a very reputable manufacturer so I wouldn't let the fact that they don't use HD in their description of the CL keep you from buying one. I am sure the CL has as good of glass as anything in it's price range if not better. Obviously it is probably not quite as good as their top of the line EL's but it is not going to make a huge difference in the performance of the binoculars. The EL's will be a little better as far as CA control and glass quality but you are paying twice the price. One really good thing about the CL's is their contrast. They have better contrast than most of their competition at their price point like the Zeiss Conquest HD 8x32. When you consider price, performance qulaity and size and weight the CL line is a very attractive binocular. But if you want the very best view you have to move up to the EL 8x32.

https://www.allbinos.com/330-binoculars_review-Swarovski_CL_Companion_8x30_B.html
https://www.allbinos.com/251-binoculars_review-Swarovski_EL_8.5x42_Swarovision.html
 
Last edited:

moyang_mm

Member
Hi and welcome.

Camera lenses are a lot more complex than binocular optics.
They often cover wide angles.
The use of special glasses and aspherics usually is to reduce the number of lens elements to sensible levels.
Zoom lenses may have 18 elements, even with special glass elements. Some broadcast lenses have 30 elements.
Some camera lens raw glass costs more than gold.
The camera lenses are often much faster optics than binocular optics.

I wouldn't worry about special glass in binoculars too much it depends on the optical reputation of the binocular.
Aspherics have been described to me as a bl..dy nuisance by a top designer.

I don't think that any binoculars contain fluorite crystal, except maybe the Takahashi 22x60.

B.

Thanks for the advice. Although EL does not use fluorite crystal, EL does have something advertised as "fluoride-containing glass, which may share similar optical characteristics with CaF2.
 

dries1

Member
You are not going to know which glass contains fluoride during the day when observing, and it seems that you are hesitant to spend the funds. Just go with the CL.

Andy W.
 

jring

Well-known member
Hi,

basically ED (extra low dispersion) glass is glass with a high amount of fluoride ions. There are quite a few kinds - most notable are O'Hara's FPL series, Hoya's FCD series, Schott's N-FK and N-PK series.

HD, XD and whateverD glass are not terms of the trade and just marketing blurb. For astro refractors the used kind of ED glass is sometimes stated by the manufacturer, usually for scopes using FPL-53, FCD-100 or the elusive russian OK-4 (only available in the form of $$$$ LZOS objectives - when they are not busy building classified stuff).

Fluorite crystal is on par with the best ED glasses - it has certain desirable properties like being bubble free (and thus generating less absorption) and the fact that most comes as finished lenses from Canon Optron who tend to deliver top notch quality, but is on the other hand very difficult to work with, quite fragile, not really waterproof and usually needs stronger curves which might generate some spherochromatism. It was used before ED glas was available and is still used by some manufacturers for visible light optics (Kowa spotters, Takahashi astro refractors and Canon lenses), but the main use nowadays is for optics in non-visible parts of the spectrum.

In general it can be said that binoculars with good color correction can be built without the use of ED glass by a competent designer. Its use makes it easier or allows for a bit smaller package.
Things are different for higher magnification optics like spotters or astro refractors, where ED glass is really needed for good results in refractive optics.

TLDR: Don't buy bins because they have ED glass - buy bins that have good color correction, regardless of the glass used.

Joachim
 

pbjosh

missing the neotropics
Switzerland
I agree with what others have said here. The difference, to me, between the CL and the EL isn't in the quality of the view, it's in the weight and the field of view. The CL is much smaller and much more compact, but has a somewhat smaller field of view. I would personally choose based upon your budget and the physical size desired - you are going to have an excellent binocular either way.
 

[email protected]

Well-known member
Supporter
The EL will have a bigger FOV, sharper edges and better CA control than the CL all around. The CL's weak spot is it's CA control IMO especially at the edge.
 

Torview

Well-known member
Hi Moyang,

I know you`v asked about the two Swarovski`s both of which I`v owned, I`d like to suggest the Kowa Genesis 8x33 which I`v just recently treated myself to.

Significantly better than the CL IMO, very close to the EL but without the flat field, overall simply superb value and well worth considering given you would like fluorite glass, these have two of Kowa`s excellent XD lenses in each tube.
 

horukuru

Here I Come !
I have both and have used the new CL 8x30 extensively in the rainforest for years. The view and weight is superb considering the price in the market.
 

kabsetz

Well-known member
I did a test of the new CL for a Finnish birding magazine when they came out. My conclusion was that if I had not been told anything about the glass types used in them, I would have automatically assumed they had some type of HD or equivalent. For my eyes, the image was quite pure and relatively free of CA, the way most good ED binoculars are. Difference to the older version of CL was obvious to me. With the older version I was always aware of CA when viewing with them, with the new ones it was a non-issue.

Obviously, we all react in our individual ways, but generally I'm pretty sensitive to CA and certainly very picky when it comes to binoculars, and I would have had no difficulty in taking the CL for my use except that I will not condescend to use binoculars without image stabilisation any more.

Kimmo
 

range

Well-known member
The CL most likely does not contain ED glass but I still like it a lot.
The CA control is relatively good, not top-notch but in no way distrubing in actual use.
The shining part of the CL is its compact size, stylish design and easy gripping(thanks to the higher position of the hinge).
 

moyang_mm

Member
Hi Moyang,

I know you`v asked about the two Swarovski`s both of which I`v owned, I`d like to suggest the Kowa Genesis 8x33 which I`v just recently treated myself to.

Significantly better than the CL IMO, very close to the EL but without the flat field, overall simply superb value and well worth considering given you would like fluorite glass, these have two of Kowa`s excellent XD lenses in each tube.

Thanks for the suggestion, Torview!
 

NDhunter

Experienced observer
United States
I did a test of the new CL for a Finnish birding magazine when they came out. My conclusion was that if I had not been told anything about the glass types used in them, I would have automatically assumed they had some type of HD or equivalent. For my eyes, the image was quite pure and relatively free of CA, the way most good ED binoculars are. Difference to the older version of CL was obvious to me. With the older version I was always aware of CA when viewing with them, with the new ones it was a non-issue.

Obviously, we all react in our individual ways, but generally I'm pretty sensitive to CA and certainly very picky when it comes to binoculars, and I would have had no difficulty in taking the CL for my use except that I will not condescend to use binoculars without image stabilisation any more.

Kimmo


Kimmo:

I agree with your thoughts, and the glass type is not always important as some brands that advertise ED or HD glass, as the chromatic aberrations may be worse than others who do not specify. This is just a advertising buzzword, and is not to be trusted.

The other thing important here is that smaller objective sizes, such as 32 or smaller do not have problems with CA as much as larger objective sizes.

The other thing is that Swarovski does things very well with lens and prism coatings, and along with overall design, the CL model does well, no matter the glass type.

Jerry
 

Patudo

Well-known member
Hello and welcome! I've read some interesting things about birding in your city and would really have liked to have seen this:

...at one point on Sunday all of the swifts suddenly stopped wheeling around the Qianmen Gate at Tiananmen and gained height fast. The reason was this Eurasian Hobby that suddenly appeared and started to hunt the swifts over Mao’s mausoleum!

Regarding your question... it seems to me that before jumping deep into all the technical aspects of two binoculars from one brand, it would be useful to have a clear idea what format (magnification x size) would best fit how you plan to use your first binocular, then research candidates in your price range. It is certainly possible to acquire an excellent birding binocular for less than $2200...
 

moyang_mm

Member
Regarding your question... it seems to me that before jumping deep into all the technical aspects of two binoculars from one brand, it would be useful to have a clear idea what format (magnification x size) would best fit how you plan to use your first binocular, then research candidates in your price range. It is certainly possible to acquire an excellent birding binocular for less than $2200...

I am pretty much settled for 8x30 or 8x32. They are bright enough for me and I do value size and weight a lot since I use binoculars mainly for hiking and outdoor stuff. I certainly do not need the absolutely best optical quality. Yet somehow knowing my gear is technically advanced makes me happy.
 

moyang_mm

Member
Hi,

basically ED (extra low dispersion) glass is glass with a high amount of fluoride ions. There are quite a few kinds - most notable are O'Hara's FPL series, Hoya's FCD series, Schott's N-FK and N-PK series.

HD, XD and whateverD glass are not terms of the trade and just marketing blurb. For astro refractors the used kind of ED glass is sometimes stated by the manufacturer, usually for scopes using FPL-53, FCD-100 or the elusive russian OK-4 (only available in the form of $$$$ LZOS objectives - when they are not busy building classified stuff).

Fluorite crystal is on par with the best ED glasses - it has certain desirable properties like being bubble free (and thus generating less absorption) and the fact that most comes as finished lenses from Canon Optron who tend to deliver top notch quality, but is on the other hand very difficult to work with, quite fragile, not really waterproof and usually needs stronger curves which might generate some spherochromatism. It was used before ED glas was available and is still used by some manufacturers for visible light optics (Kowa spotters, Takahashi astro refractors and Canon lenses), but the main use nowadays is for optics in non-visible parts of the spectrum.

In general it can be said that binoculars with good color correction can be built without the use of ED glass by a competent designer. Its use makes it easier or allows for a bit smaller package.
Things are different for higher magnification optics like spotters or astro refractors, where ED glass is really needed for good results in refractive optics.

TLDR: Don't buy bins because they have ED glass - buy bins that have good color correction, regardless of the glass used.

Joachim

Joachim, thank you for the very informative post. I've learned a lot. Really appreciate it.
 

Tringa45

Well-known member
Europe
I know you`v asked about the two Swarovski`s both of which I`v owned, I`d like to suggest the Kowa Genesis 8x33 which I`v just recently treated myself to.

Significantly better than the CL IMO, very close to the EL but without the flat field, overall simply superb value and well worth considering given you would like fluorite glass, these have two of Kowa`s excellent XD lenses in each tube.

I have the 8x33 Genesis and my wife has the 8x30 CL Comanion II, so I have often compared them. It's really six of one and half a dozen of the other.
The CL is lighter, compacter and with that extra mm of eyerelief is a little more comfortable for glasses-wearers. Its build quality is also a little better than the Kowa. The latter though has a larger FOV and the best colour correction I have seen in any binocular, significantly better than my 10x42 EL Swarovision.

John
 

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