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Does (ED) Glass Really Make a Set Better than One Without It? (1 Viewer)

MUHerd

Well-known member
Hey all,

I have been going thru all kinds of specs and reviews and such looking for 8X binos that are in my range. What I have seen many times is that a set will be listed as having ED Glass and Phase Coatings, but they will not be thought of as highly as other binos that don't have those features.

I thought there are certain things that signify binos as being in the TOP TIER. Those things are Phase coatings and ED Glass. Well, maybe the phase coatings isn't such a high dollar feature any longer. I at least thought that when you compare 2 sets and one has ED Glass, that set is going to perform better in lower light and therefore be the better set of binoculars. Even the Zeiss Terra ED is not thought of as highly as some others that don't have the ZEISS pedigree and the ED Glass that they use.

When you can't go out and physically look at these different models of binos, you have to rely on reviews, postings on forums and specs to decide. You think that certain things are a sure sign of a better bino with superior glass elements, but that isn't so. As an example the Leupold Mojave 8x32 is very highly recommended and thought of and it doesn't have ED glass and when compared to others that do have it, the Mojave still stands above them.

This is the kind of stuff that makes it very difficult for people like me that are not that experienced with binos and can't try out a lot of these that are mentioned.

What do you all think?

Thanks again for your help.
Larry
 
Hey all,

I have been going thru all kinds of specs and reviews and such looking for 8X binos that are in my range. What I have seen many times is that a set will be listed as having ED Glass and Phase Coatings, but they will not be thought of as highly as other binos that don't have those features.

I thought there are certain things that signify binos as being in the TOP TIER. Those things are Phase coatings and ED Glass. Well, maybe the phase coatings isn't such a high dollar feature any longer. I at least thought that when you compare 2 sets and one has ED Glass, that set is going to perform better in lower light and therefore be the better set of binoculars. Even the Zeiss Terra ED is not thought of as highly as some others that don't have the ZEISS pedigree and the ED Glass that they use.

When you can't go out and physically look at these different models of binos, you have to rely on reviews, postings on forums and specs to decide. You think that certain things are a sure sign of a better bino with superior glass elements, but that isn't so. As an example the Leupold Mojave 8x32 is very highly recommended and thought of and it doesn't have ED glass and when compared to others that do have it, the Mojave still stands above them.

This is the kind of stuff that makes it very difficult for people like me that are not that experienced with binos and can't try out a lot of these that are mentioned.

What do you all think?

Thanks again for your help.
Larry

Good advertising need not be accurate or even meaningful; it needs only to be believed. And plenty of people are easy pickens because many people who are so ardent about technical accuracy lack the experience to know what IS and IS NOT technically accurate.

If done correctly, it makes a better product. WORDS, however, don't make it so. Many times the legends of the industry make a better product with spherical optics of traditional glass than the wannabe startups that capitalize on those with more opinions than experience to promote their products for them. :cat:

Bill
 
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Hi Larry, I'm no optics expert but I've spent 18 years and too much money trying just about everything to try and find the 'perfect' binoculars for me (Obsession...it's not just a perfume!;))
AFAIK, ED glass is designed to eliminate CA or colour fringing, green or purple fringes you get when looking at high-contrast images, right where a dark image meets a light one or vice-versa...think dark branches against a pale grey sky. No glass I've tried eliminates it entirely. Some expensive 'ED' glass does a good job. So does some inexpensive non-ED glass. Some people aren't that bothered by CA. It used to drive me nuts. My current fave bino is Nikon SE 8x32. It doesn't boast ED glass, but controls CA well enough so that it doesn't bother me. If you like, you can spend 2k or thereabouts on expensive glass that does a better job.
(I once had a pair of cheap 20x100 binos for seawatching that were very good in most respects, but their CA made it seem like Hallowe'en everyday...)
Phase coating is for roof-prism binoculars. I can't remember the Science Bits and they hurt my head. My Nikon SE are porros so they don't need it. Most good roof-prism binos nowadays have it...so foggedaboudit.
There are lots of mid-priced binos now that boast ED glass and have PC. The forum is replete with testimonials to Mavens, Tracts, Hawkes, Opticrons, etc. If you miss the bus, don't worry, there'll be another one along soon.
(My Nikon SE are optically equal or better than anything I've ever owned as regards CA and all other image aspects. I'd love if they had wider FOV and waterproofing, but hey. Importantly, they can't be bought new anymore.)
Try lots of binos in stores, etc. Don't rush into anything. Then when you buy them, stop reading reviews or looking at new binos. For that is truly the Path to the Dark Side (that I have walked:-O)
 
Hey all.

I am beginning to get the idea that one should restrict purchase of new binos to those that he (she) can walk into a store and physically examine. It doesn't look like the specs and product info is much good at all when you don't have a benchmark to go off of.

Thank you all for your help.

Larry
 
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I thought there are certain things that signify binos as being in the TOP TIER. Those things are Phase coatings and ED Glass.

Hi,

my SE 10x42 have neither ED glass nor phase coatings... I bet you, they beat all 10x40 bins labeled ED... the true alphas usually don't comment on the glass used even if it is ED (or rather Sonderglas as one would say over here in Teutonia ;-)

Regarding phase coatings - yes, any pair of good roof bins should have them, my SE are porros and thus don't need them. Zeiss for example has stopped using the P label for phase coated in their models as all current roof bins made by Zeiss have it.

For top tier roofs, dielectric mirrors would also be nice... silver has some weaknesses in the blue spectrum and can also get dull over many years - it shouldn't if the glass keeps its nitrogen filling though.

Joachim
 
When a seller sells non ED models for less and ED models for more, the ED models most often are better. But there are brands that ruin both efforts.
 
I am beginning to get the idea that one should restrict purchase of new binos to those that he (she) can walk into a store and physically examine. It doesn't look like the specs and product info is much good at all when you don't have a benchmark to go off of.

Going to a brick & mortar store is certainly a good strategy, especially so as ergonomics also plays a role and this is a quite personal thing, as is the question how sensitive sb is to CA or rolling ball.

Or take advice from those who have used pair of bins or three...

Joachim
 
Hey all.

I am beginning to get the idea that one should restrict purchase of new binos to those that he (she) can walk into a store and physically examine. It doesn't look like the specs and product info is much good at all when you don't have a benchmark to go off of.

Thank you all for your help.

Larry

Larry,

You are correct. After gaining some semblance of optic terminology and possibly what power to meet your needs (you've already done most of this), "Trying before Buying" is always recommended! There should be a plenty of the big B&M sporting goods stores in\around your city that you can live in for a few hours. Take your time, glass with as many optics as you can and try both in-store and out of store, maybe even at dusk\dark for low light capabilities.

Be careful though...90% of sales staffs can mislead with uneducated suggestions and hear-say on optical specs and recommendations. Observe, look, listen and try-for-yourself. Then take a breath, think about your choices and maybe ask more questions of the BF membership. The more you know and understand, the better suited your choices will be, For You! :t:

Ted
 
ED is very well worth it and recommended. Color fringing is significantly reduced or removed during normal use, unlike non achromatic designs, especially porro prisms.

With ED , you also dont have to keep your eye and head placement as critical, because fringing is also significantly reduced off axis.
 
"Be careful though...90% of sales staffs can mislead with uneducated suggestions and hear-say on optical specs and recommendations."

90%!? The eternal optimist. I rush on to say most do this with no malice in mind. It’s just they don’t know, their bosses don’t know enough to train them, and most of the info in magazines and on the net drips with erroneous information. Example ahead:

Enter The Experts

Magazines offering an aura of fidelity often rely on their own stable of experts who, when it comes to optics, may not be experts at all. Instead, these freelancers may write about car stereos on Monday, fishing gear on Wednesday, and the best pizza in town on Friday. There’s no doubt if they offer truthful opinions about what they like and what they don’t, those opinions can be worthwhile. Still, when it comes to understanding more than a few basic buzzwords and phrases, which have been circulating for decades, being a master birder, serious amateur astronomer, or seasoned hunter or mariner makes a person no more of an expert on binoculars and optics than being a disk jockey makes one an expert on the design, manufacture, and performance of microphones.

Following are some examples found in influential sailing magazines. Birding, hunting, and amateur astronomy magazines are just as prone to have serious errors. Being with Captain’s Nautical Supplies at the time these were just more prominent.

1) “In the loosest sense, ‘marine’ binoculars simply means ‘waterproof,’ which means they have some sort of rubber armoring.”

Not so! Many inexpensive, rubber armored “marine” binoculars have little or no waterproof/fog proof integrity. On the overleaf from that comment was a comparative chart stating a certain binocular was “nitrogen filled,” implying gas tight/watertight integrity. In reality the binocular was an inexpensive center-focus model with two-piece body styling not even promoted as waterproof by the manufacturer or importer and incapable of holding a nitrogen charge. Did the writer make up that part to add a few words to the article or did he or she just interview the company’s representative who knew a great deal about sales and not so much about binoculars?

Another read:

2) “Center-focus models have a speed advantage over individual-focus models, but don’t compensate for varying eye strengths.”

That’s so wrong it should have been an embarrassment to the writer and the editor. Of course they compensate for “varying eye strengths”; that’s what focus mechanisms do, whether on center-focus or individual-focus instruments.

********************
A center-focus and Individual-focus binocular
********************

Finally:

3) “Porro prisms are used in most marine binoculars because they provide greater depth of field than roof prisms.”

This faulty passage only touches on a half-truth as the lines between depth of field and a 3-D effect become blurred. Do marine binoculars employ Porro prisms? Yes, most do. Do those binoculars provide a greater 3-D effect than their roof prism cousins? Over a relatively shallow distance, yes. Even so, the type of prism is only responsible in a peripheral way.

Because of the size and configuration of Porro prism clusters or mountings, the telescopes must be spaced farther apart. This spacing is what creates the stereoscopic view that produces the illusion of depth; the prism type has nothing to do with it. Even so, this 3-D effect diminishes with distance and is appreciated more by the naturalist and hunter than the mariner, whose targets are usually at greater distances, and considerably more than the amateur astronomer whose targets are seen at infinity.

A binocular, telescope, or camera can only be focused precisely on one object or plane at a time. Before or after that distance images will grow gradually more defocussed. The range in which the observer can appreciate a seemingly focused image constitutes the depth-of-field. Clinically, this term relates to monocular vision. However, the 3-D effect created by the visual cortex of the brain is widely accepted as depth-of-field as opposed to depth perception.

From Wikipedia:

“Stereopsis was first explained by Charles Wheatstone in 1838: “… the mind perceives an object of three dimensions by means of the two dissimilar pictures projected by it on the two retinæ ….” He recognized that because each eye views the visual world from slightly different horizontal positions, each eye's image differs from the other. Objects at different distances from the eyes project images in the two eyes that differ in their horizontal positions, giving the depth cue of horizontal disparity, also known as retinal disparity and as binocular disparity. Wheatstone showed that this was an effective depth cue by creating the illusion of depth from flat pictures that differed only in horizontal disparity.”

********************
Photo, Illustration, or Comment Show a Porro prism cluster and how mounting creates the need for separation.
********************

So how do these things find their way into our regional and national magazines? Mark Twain asked a similar question of his publisher, William Dean Howells, who replied:

“Because paper never refuses ink.” (Attributed)

A Story: In early September 2015, someone in Orlando, Florida lost possession of his pet king cobra, “Elvis.” In October the 8-foot snake was captured hiding under a clothes dryer and certain people in the local media, including one television newscaster, announced the “kingsnake” had been found.

Although comparing a large, deadly king cobra to a small, non-poisonous kingsnake is like comparing a new Rolls-Royce to a used Volkswagen beetle, all those inexperienced or cranially challenged announcers and editors had the power to influence the unwary. And if such easy to find information can be that misunderstood and handled so carelessly by those we have come to trust, how much easier would it be for busy magazine writers and editors to misconstrue a topic as foreign to most as binocular optics?

Bill
 
ED is very well worth it and recommended. Color fringing is significantly reduced or removed during normal use, unlike non achromatic designs, especially porro prisms.

With ED , you also dont have to keep your eye and head placement as critical, because fringing is also significantly reduced off axis.
I'd agree with that... except... I'd put a huge caveat up front saying something like: "All else being equal, while depending on the optical design and the quality of the ED glass being used..." before proceeding to "Colour fringing is significantly reduced..."

I'd also note that in the real world "all else" is seldom "equal".

I have binoculars without ED glass that control CA better than others with highly-touted claims to use ED elements. I don't doubt those claims, nor do I doubt that those ED glass elements helped. I'd just hate to see how hideous the CA would have been without using ED elements!

I think good design is probably at least as important as the glass used, and I also know that there are different types and grades of ED glass, making correct selection - which is part of good design - quite important from an optical point of view. I suspect, though, that the use of ED glass is intended more for marketing effect that optical effect a little more frequently than I'd prefer.

That's not to say that use of ED glass is a bad thing. It isn't, it's often a very good thing indeed. But not always, and marketing claims should be subjected to sceptical examination.

...Mike
 
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Hi,

we can safely say that ED glass is one tool for the optics designer to reduce CA in a design, as is making the design slower and thus the bins longer.

If ED glass is used to make a design with good CA great or turn a kaleidoscope into barely acceptable we don't know without actually testing the bins.

Btw. all modern binocular objectives are at least achromatic doublets, sometimes even triplets.

Joachim
 
Of the information above I'd think the most important to keep in mind is in Mfunnell/Mike's post. Sorry about the abridging Mike! The benefit of "ED" glass
...depend on the optical design and the quality of the ED glass being used...good design is...at least as important as the glass used, and...there are different types and grades of ED glass, making correct selection [in design] quite important from an optical point of view. I suspect...that the use of ED glass is intended more for marketing effect tha[n] optical ef[f]ect a little more frequently than I'd prefer...
 
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I'd agree with that... except... I'd put a huge caveat up front saying something like: "All else being equal, while depending on the optical design and the quality of the ED glass being used..." before proceeding to "Colour fringing is significantly reduced..."

I'd also note that in the real world "all else" is seldom "equal".

I have binoculars without ED glass that control CA better than others with highly-touted claims to use ED elements. I don't doubt those claims, nor do I doubt that those ED glass elements helped. I'd just hate to see how hideous the CA would have been without using ED elements!

I think good design is probably at least as important as the glass used, and I also know that there are different types and grades of ED glass, making correct selection - which is part of good design - quite important from an optical point of view. I suspect, though, that the use of ED glass is intended more for marketing effect that optical efect a little more frequently than I'd prefer.

That's not to say that use of ED glass is a bad thing. It isn't, it's often a very good thing indeed. But not always, and marketing claims should be subjected to sceptical examination.

...Mike

Mike has said it all. Not all ED glass is equal and some designs manage very well without it at all.
Two cases:
Meopta's MeoStar B1 8x32 is a cracking little bino that has no ED glass (although its Cabela's Euro cousin does) and it is hard to provoke CA with it.
Kowa's Genesis 8x32 has two ED elements and it is even harder to provoke CA with and in fact it may well be the equal to a Zeiss FL.

The latter seems to support all the claims made for ED glass while the former does very nicely without it.

Don't forget that perception of CA and sensitivity to it is to some extent down to the individual using the bins as well as the design and execution of the binos. As always the moral is to try before you buy. And this might mean setting a weekend to one side and getting up really early on Saturday morning and driving as far as it takes, or at least contacting a store with a sympathetic returns policy.

Lee
 
90%!? The eternal optimist. I rush on to say most do this with no malice in mind. It’s just they don’t know, their bosses don’t know enough to train them, and most of the info in magazines and on the net drips with erroneous information...

Bill

No way, Bill. If it's in print, on the air or circulating on the net, it Must be True! :eek!: :'D

Actually, I was going to state "98%", but then I wouldn't have been As Optimistic! ;)

Ted
 
"Actually, I was going to state "98%", but then I wouldn't have been As Optimistic!"

No, but MUCH closer to accuracy. I frequently get into trouble for not mincing words and failing to give the benefit of the doubt to those who are making a fortune from taking advantage of that doubt. Were it not so, I could be financially well-off today. But then, without health you HAVE nothing; without integrity you ARE nothing. I spent my youth thinking poverty was for rich folks. But, those illiterate parents taught me right from wrong.

Bill
 
Larry,

Since the mid eighteenth century people have been combining lenses made with glasses with different dispersion and refractive index characteristics to reduce chromatic aberration. As others have mentioned it is quite possible to produce a high level of CA control without ED glass, but the low dispersion properties of ED types of glass, sometimes also referred to as fluorite crown, make the job easier. The lowest dispersion optical material is crystaline calcium fluoride known as fluorite. It expensive to manufacture, difficult to work with and is rather fragile but is occasionally used in high end optics such as the Kowa 883 spotting scope. At one time synthetic glasses were expensive and reserved for expensive products but in the last twenty years a range of much lower priced fluorophosphate ED glasses have become available. At the lower end the dispersion properties are no better than traditional barium crown glass (BK7) and may be inferior in other ways and it's use is no more than a marketing tool. At the other extreme, FCD100 from Hoya boasts characteristics comparable with mineral fluorite and can produce exceptional results.

I would have to go along with others and encourage you to try stuff for yourself and certainly be very wary of what the sales person tells you. I'm constantly being told some nonsense about one model or another is brighter, sharper, has better CA performance etc. It may not always be a cynical sales tactic. Individuals differ considerably in their visual capabilities and you may well justfiably disagree.

David
 
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Yes, believe your eyes only!

As others have suggested, David being the last-only believe what your eyes tell you-as yours are as different than any here-and tell you what you really need to know.

It would be nice if you could try all the offerings available in stores, but it's not always possible. So, either price plays an important factor in your purchase (no returns-private sale) or having a return policy that you can live with for money back with shipping paid by you for the privilege of trying them for yourself.

Sure, you can read other's reviews and gleam what you can from them for different qualities that you might want, but only your eyes can tell you for sure if they meet your needs. And of course, those needs can be as varied as there are binoculars on offer, or the people who use them.

In my heyday, I bought many more binoculars than I sold, so I have an excess of very nice ones that I just kept because they did something very well-and were pleasing to use. I only sold off those I was sure were not for me-which was a small percentage of what I bought overall.

I would bet that there are many of us who did this, and have many more than we actually use on a daily, weekly, monthly or yearly basis to any extent. It is just the collecting or gathering instinct that we can't overcome at times.

What I use on a daily basis is one of the least expensive binoculars that I bought, as a new binocular, and it still gives premium binoculars a run for the money for my non-demanding usage. No doubt there are better ones out there, and some of mine are among them. But my favorite for house use is a 10x Porro, namely the Nikon Aculon 10x42.

I also have this same one in 7x35, and 16x50, and both are great too for the money invested, which I will say is about the least you would dare spend on a decent quality binocular. But Nikon's multi-coatings and design seem to make them work, whatever their specs for their lowest priced Porro binoculars-there is a quality there that is not expressed in dollars only. And why I have 3 of them at hand.

For me, it's not always black and white either-sometimes it takes me a while for it to sink in what I like and don't about them, so often that will take me beyond the 30 day return period of the generous retailers. So don't expect a lightening bolt to strike and you make claim that these are the best things since bread and peanut butter-only to find out later that others do what you want better that you thought possible at the time.

It's a process, and you are the captain of the ship you sail. Make it so.
 
When the vast majority of posters are saying the same thing,
(here or CNs) they are probably right;
when posters are divided, then buyer beware

but then there are always optics I love, and most do not;
or most love and I do not.

edj
 
When the vast majority of posters are saying the same thing,
(here or CNs) they are probably right;
when posters are divided, then buyer beware

but then there are always optics I love, and most do not;
or most love and I do not.

edj

Watch out Edj, I was gently pulled up elsewhere on BF for using the word 'love' about binos. But hey, whatever floats your boat :t:

Lee
 
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