Please read if you are about to buy high end bins (1 Viewer)

mpedris said:

Folks,

Let's try to have some peace here for the sake of ALL BF members. It may be worthwhile to remember that at their peaks, all great civilizations of the world tolerated diverse views and dealt with disagreements as gentlemen. The Dark Ages and the fall of knowledge (of arts, sciences, literature, music, etc) was a direct result of intolerance and the people's inability to deal with disagreements. Fortunately, the Arab world, at the time extremely tolerant of diversity, kept this knowledge alive.

Let's try to tolerate and respect everyone's knowledge so that all members may benefit from several points of view and come to their own conclusions about truth. This would ensure that BF does not fall into a period of Darkness...

...IMO.

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Agreed

Chris

are we a great civilisation at it's peak then?

or entering a new 'dark age'

laika said:

If you really mean this, then it is meaningless to discuss binoculars and to read tests. If some says Leica Ultravid 8x42 gives a better view than Leica BN 8x42 i must remember he is talking about one specific binocular?
Of course not all binoculars are exactly like,but there are of course less differences in quality in a Ultravid than in low cost binocular. So i feel it is not incorrect to talk about models generally. Why else do we buy expensive binocular models if not the quality is the reason?

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This is correct. As I said on an earlier thread, there are less inconsistencies in binoculars and spotting scopes from manufacturers such as Leica and perhaps Swarovski, cheaper mass-produced instruments generally receive less rigourous QC. But even with the manufacturers at the higher end of the market, there are inconsistencies. I am sure the manufacturers would refute this vigourously, but over twenty years in the optics industry, I have seen this on so many occasions.
Strictly speaking, an instrument must be assessed on its own merits, but those merits should not be accepted as being constant for every other instrument of the same model. It is not that instruments of the same model can not be the same, but it is just that they are often not the same. In other words, QC and manufacturing errors. The design and tolerances on paper for a particular instrument may look better or worse compared to another manufacturer's instrument design and tolerances. The finished article is often different from its designed state on paper.
Four examples that leap to mind immediately.
1.) I have in my stock five Maksutovs of 7" aperture. All excellent, but all with a different wavefront error rating. One is 1/6th, two are 1/7th, one is 1/7.5, one is 1/8th. All are stated as minimum 1/6th wavefront error. All meet the minimum requirement, most are better. All will produce an excellent performance. The important thing here is that all meet the required standard, and most are better, but still, all are inconsistent. However, I know what level of CA, LSA, astigmatism etc these instruments have. I don't have to be concerned that one or more will be below standard. Now imagine yourself as a customer that knows this information, which one do you choose? They are all the same price.
2.) I also have in stock three of the same model 15X70 Japanese porro prism binoculars for astronomy. All three are different in that one is collimated correctly, the other two are not. One has an obvious difference in general image sharpness to the others, one has a difference in performance between left and right sides of the binocular. Each are £150. Which one do you choose? As a consumer you purchase the binocular, and assess it on what you see, without knowing exactly why you are seeing what you are seeing. It gets around the astro community that Binocular 15X70 So and So make, is a good or poor performer, all based upon whether the QC has been performed, not upon the design of the binocular. £150 binoculars cost £30 to make, so is it any wonder that QC is missing here.
3.) I also have a pair of Minox 10X58 ED binoculars in my showroom retailing for £800. They are out of collimation. Supplied by Leica UK.
4.) A few weekends ago, myself and my partner went to a well known birding reserve for a pleasant Sunday activity. This reserve has a reception building and an optics shop attached to it. After a couple of hours wandering around the reserve, we came back to the building for a cup of coffee and a look round the gift shop.
I sidled into the optics shop just out of interest. A man had just bought a pair of Nikon 8X32 roof prism binoculars, and had them out of the box trying them. There was another of the same model on the window sill (probably a shop demo unit). They had a ridge on the body of the binocular that made them sit very comfortably in the hand. Very nice sharp bright image, although a little too much CA for me. The man was oohing and aahing over a 'milkiness' (his words not mine) in the image of his new binocular. The shop owner could see nothing untoward, and said they looked fine.
I asked whether I could have a look. The man agreed and and I compared them to the demo unit. The 'milkiness' was an internal reflection in the left hand barrel somewhere in the prism housing. It produced a crescent of unfocussed light most noticable at the bottom part of the field of view. This reflection was not there in the demo unit. To me, it was an easily remedied problem (even though if the binocular was waterproof it would require Nikon UK to do something about it). To the customer, it was instrumental in forming an opinion of that model. To the shop, it was a lost sale to them (they did not have another one in the shop), but I have no doubt that it will be passed on to the next customer who chooses this model.
I would probably have bought the demo model and asked for a small price reduction. The customer wanted a new one straight out of the box.
These Nikon binoculars were not cheap.
Four examples of inconsitencies, of varying weight and magnitude of importance. Sometimes it is just easier to ignore it all and pretend that all are consistent. Talking about optics, writing about optics, reviewing optics is much easier this way. The reality is somewhat different to what we are led to believe reality is. But isn't this the way with all aspects of life.

best regards
Chris

jebir said:

Basically, I think most things have been said that need to be said in this thread. However, IMO the reason for the fiery debate here is the different meaning that different individuals lay in the word "resolution" and how we succeed in communicating this to each other.



An optician or an astronomer who is building his own telescopes may think of the resolution in terms of the theoretical limit. However, I don't think I am wrong when I state that most professional consumers of optical instruments, e.g., photographers, optical microscopists, electron microscopists, and some times even astronomers(!), mean by "resolution" the ability of a given optical instrument to produce separable images of two object points or lines. The instrument is then seen as a black box and the manufacturers just provide the number characterizing the actual performance: resolution=separation between separable points or lines (of course - there are additional quality mesures). Who cares if the real "resolution" is limited due to one or the other reason if one can't do anything about it anyway?

Unfortunately, producers of birding optics do not provide any measures of the optical quality of their products. Therefore birders trust their own eyes when judging the image quality of a given instrument and it is natural to talk about the amount of detail that can be seen as the "resolution" just as when talking about camera lenses or other instruments. It would certainly be helpful to discuss birding optics if we could have some measure of what kind of detail our gear is capable of. After a while, we could use the numbers like we use horespower and torque when judging a car engine.

My point is that it isn't wrong saying that one can see a difference in the "resolution" between two instruments even if it isn't the diffraction limited resolution that is seen.



Right, communicating only with written text in English (which for many aren't their mother toungue) certainly pose high demands on our abilities to communicate. Here we are a bunch of birders being opticians, physicists, plumbers, nurses, etc. trying to figure out how our binoculars and scopes work. IMHO, it is therefore not always useful to use fundamental laws and rules - simply because it is a language that isn't always understood.

I think we are (I am) quite off topic so I will not talk about semantics and communications anymore.

Cheers, Jens.

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An optician or an astronomer who is building his own telescopes may think of the resolution in terms of the theoretical limit. However, I don't think I am wrong when I state that most professional consumers of optical instruments, e.g., photographers, optical microscopists, electron microscopists, and some times even astronomers(!), mean by "resolution" the ability of a given optical instrument to produce separable images of two object points or lines. The instrument is then seen as a black box and the manufacturers just provide the number characterizing the actual performance: resolution=separation between separable points or lines (of course - there are additional quality mesures). Who cares if the real "resolution" is limited due to one or the other reason if one can't do anything about it anyway? Jens Quote.

It matters because the consumers of a market can do something about it. It happens in astronomy, where the finest APO refractors, Maksutovs and Newtonians are all capable of reaching their resolution limits, becasue care is taken to ensure that aberrations are either not present or kept to an acceptable minimum. It happened in birding optics twenty years ago, when ED glass and Calcium Flourite were introduced into spotting scopes, after being used in astro refractors and telephoto lenses.
It matters because if consumers demand better manufacturing tolerances and improved QC strongly enough, it will happen. If manufacturers understand that consumers have become aware of these issues, then the more pro-active manufacturers will take a lead, it is a marketing opportunity for them. Sure it will raise prices for a while, but they will fall, they always do, competition will see to that.
We should care, because incorrect terminology leads to misinformation and general confusion, and there is enough of that about.
Perhaps Jens is right. Maybe we should lay this one to rest. Besides, I am spending far too much time writing and arguing on a Forum site, instead of attending to my optics business.

Best regards
Chris

Tim Allwood said:

are we a great civilisation at it's peak then?

or entering a new 'dark age'

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Tim: Isn't that a picture of Johnny Rotten by your name?

Now I can understand someone famous not using their real name, but the picture is a give away don't you think 'Tim'?

taken as a compliment

Steve Ingraham has published on his site - Better View Desired - measured resolution for various binoculars. He is well aware of sample variation and I think has tested several samples of some of the instruments. I have used or owned many of the instrument that he has tested. These are mostly high end instruments. I have measured the resolution of the ones I have owned and I get qualitatively identical results to Steve Ingraham. This suggests that sample variation of properly collimated high end binoculars is not significant. (I say qualitatively rather than quantitatively since I did not use the same test target, hence could not directly compare.) I expect that the optical performance of these binoculars - assuming correct collimation - is largely determined by optical design, choice of coatings, control over glass refractive index and the tolerances applied to the optical elements i.e. radii and surface finish.

The result that matters to me is the noticeable difference in resolution between the mid-sized (~30mm objective) 8x roof prism binoculars I have tested, and the full-sized (~40mm objectives) 8x ones. The difference is enough to make the difference between making and missing an id when a bird is distant and so I consider it meaningful.

I heard from a well known dealer who seems very honest that he has seen several brand new Nikon 8x42 HG that were out of collimation straight out of the box. I too have used one that was out of collimation (though one dealer examined them and missed the fact). This clearly agrees with Chris's experiences and yes I agree with him when he states that this is not acceptable.

This does imply that anyone buying a binocular really should test them carefully, and make sure they test the sample they intend to buy. In my experience dealers will allow you to do this. Reviews are just a guide.

On a side note I find it interesting that he sees objectionable CA through the Nikon 8x32 HG. I agree with that, though an awful lot of people do not see it. I even had a forum full of amateur astromers tell me quite clearly that such small objectives cannot produce noticeable CA! Believe your own eyes is the probably the conclusion.

On a related note, about a year or so ago I heard from Steve Ingraham that Zeiss had made him an offer that he "could not refuse". Some months later Zeiss announced that they had hired him as a consultant. Presumably Zeiss, one of the world's leading optics manufacturers, have a high opinion of the man.

Pretty sure that's true Leif, but why would an optics company employ an independent expert?
If he's that expert and their products are so good they wouldn't need to pay him....

the people won't be fooled again will they?

Tim - perhaps the reason they are employing him is that their bins, rightly or wrongly, are getting a luke warm reception and they hope he can tell them what they are doing wrong. Just a guess.

Anyway how can you be fooled? As long you purchase based on your own tests and not reviews you'll be safe.

Tim Allwood said:

Pretty sure that's true Leif, but why would an optics company employ an independent expert?
If he's that expert and their products are so good they wouldn't need to pay him....

the people won't be fooled again will they?

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I'm not quite sure about that last sentence. How do you mean?

pduxon said:

Tim - perhaps the reason they are employing him is that their bins, rightly or wrongly, are getting a luke warm reception and they hope he can tell them what they are doing wrong. Just a guess.

Anyway how can you be fooled? As long you purchase based on your own tests and not reviews you'll be safe.

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This makes sense and is along the lines I was thinking. Zeiss are a leading optics company, making healthy profits, but as Pete says, the Victory range does not seem to have enjoyed the success Zeiss were expecting. I imagine that someone at Zeiss HQ felt pretty miffed. I assume that Steve Ingraham is being employed to give advice, and obtain feedback from real birders. I might be wrong!

I believe that when Swarovski designed the EL range, they got together a group of experts, including respected birders, in order to better target the intended market.

I'm not sure what Leica and Nikon do. Maybe Leica just employ celebrity birders to endorse their products? Buy up all the opinion formers and you can't go wrong.

Pete: Seems I am alone in liking reviews as they give me an idea of what is around and what is worth testing.

Leif said:

Pete: Seems I am alone in liking reviews as they give me an idea of what is around and what is worth testing.

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Leif!
Me too like to read reviews,but i don't trust them blindly. Not so much because of variation in quality from one sample to another,but because all reviews are more or less subjective opinions. That's why i like to read a lot of them.
laika

Leif said:

[SNIP]
On a side note I find it interesting that he sees objectionable CA through the Nikon 8x32 HG. I agree with that, though an awful lot of people do not see it. I even had a forum full of amateur astromers tell me quite clearly that such small objectives cannot produce noticeable CA! Believe your own eyes is the probably the conclusion.

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You have to be careful when talking about color problems in binoculars. People often lump them together into CA - chromatic aberration, but there are actually a number of different color problems with binoculars. Secondary color is a variation of focus on-axis with wavelength. It is not something you will see in 7 to 10 power binoculars. Lateral color is a variation of magnification with wavelength. Although lenses can have this, the main contributor is usually the eyepiece. This isn't too surprising since the main objective covers a view angle from 6 to 8 degress or so, while an eyepiece covers from roughly 50 to 67 degrees. This is visible as color fringes along borders, and the fringing gets worse as you move toward the edge of the field.

Clear skies, Alan

Leif said:

Pete: Seems I am alone in liking reviews as they give me an idea of what is around and what is worth testing.

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I do enjoy reading them, IF they come across as impartial (and that doesn't mean agreeing with me). Its a pity that BVD tended to ignore Leica in later years. The reason I've enjoyed the Alula reviews is the guy doesn't seem to have an axe to grind.

As an aside. Are a bin like the Swaro EL 8x32 really worth the extra £300 over the SLC 8x30? Or is this a case of human desire to want the latest model regardless of price.