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What is Meopta doing?

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Old Sunday 13th May 2018, 14:22   #76
dries1
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Regarding Meoptas costings, there is something being done to the coatings.

Meopta 8X42 B1 serial 12xxxx
Meopta 8X42 B1 serial 15xxxx

There is a difference, while I have the later serial # in for service (focus wheel) when it gets back I need to do a more advanced comparison. Meopta is definitely doing something with the coatings. There was a thread earlier on this discussing the 7X42 since 2005 to present regarding coatings.
Regardless of silver+dielectric I could careless about the formula. They are without a doubt the best mid range glass out there in 8X42, they are a much better glass than the Nikon MHG, which after viewing those for a while have major pincushion distortion when panning.

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Old Sunday 13th May 2018, 19:16   #77
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Originally Posted by Chosun Juan View Post
I think your conclusion is correct - the mirror is a silver based dielectric coating. We aren't of course privy to how many 'enhancement' layers on top of the protected silver coating it takes before it constitutes a dielectric coating.
Thanks for your help in coming to this conclusion. It's finally making sense to me. (Thanks also to David for pointing out privately that concerns about oxidation of silver [based?] coatings are easily exaggerated.)

I do wish it were possible to ask and answer questions like this without stumbling into old arguments about what one should worry about and what's good enough for whom and so on... it's only a matter of information. What we choose to do with it is up to each of us.

Last edited by tenex : Sunday 13th May 2018 at 19:46.
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Old Sunday 13th May 2018, 20:10   #78
Gijs van Ginkel
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tenex, post 77,
A polished silver layer exposed to air oxidizes very quickly, it turns black (basic high school chemistry). When kept under a nitrogen atmosphere in a roof prism binocular the chances are very small that this occurs. It becomes almost zero, when the silver layer is protected by a spectrally neutral transparent layer. Nevertheless it sometimes occurs as I found out with older binoculars which needed to be repaired for that reason. But that is no reason for concern, since it very rarely occurs.
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Old Sunday 13th May 2018, 20:26   #79
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Gijs,

a question in this respect:

I remember having read in one of the optics books (I have not yet been able to find that quote again) that dielectric coating in a roof prism, with its higher reflectivity, would usually lead to more brightness in the image, but that silver coating would actually still provide the better contrast (the Meoptas show very good contrast in my view).

Do you have an opinion on this?

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Old Sunday 13th May 2018, 20:55   #80
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Canip, post 79,
No I do not have an opinion about it.
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Old Sunday 13th May 2018, 23:09   #81
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Quote:
Originally Posted by Gijs van Ginkel View Post
tenex, post 77,
A polished silver layer exposed to air oxidizes very quickly, it turns black (basic high school chemistry). When kept under a nitrogen atmosphere in a roof prism binocular the chances are very small that this occurs. It becomes almost zero, when the silver layer is protected by a spectrally neutral transparent layer. Nevertheless it sometimes occurs as I found out with older binoculars which needed to be repaired for that reason. But that is no reason for concern, since it very rarely occurs.
Gijs van Ginkel
The tarnishing though is silver sulfide caused by minute quantities of hydrogen sulfide in the environment.
Irrespective of whether there are itermediate dielectric coatings between the prism surface and the silver reflective layer, the protection layer does not need to be transparent. It could be completely opaque.

John
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Old Monday 14th May 2018, 03:28   #82
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Originally Posted by Chosun Juan View Post
Adhoc, I think things have progressed a bit since then, from the back rooms populated by propeller heads, to industry supply chains, and even into the public domain. See the links in my initial post to see some of the materials widely in use. Even this Wiki entry contains some of the common materials https://en.m.wikipedia.org/wiki/Optical_coating

With the properties of various common and economically viable materials known, and given the integer fractions of wavelengths thicknesses employed, I'm sure that computer simulation programs exist that could accurately predict the resultant reflectance values and hence colour spectra of any particular concoction or proposed proprietary recipe that the designers would like to dream up. Such calculations would be a lot easier than Computational Fluid Dynamics (CFD) which is now an essential part of the F1 aerodynamics development concept, design, and pre-manufacturing cycle.

This article is a summary of the now decades old MIT research on 'perfect mirrors' http://news.mit.edu/1998/mirror

Chosun
Chosun,
Thanks for those links also.
Interesting to think: Is such software now available as third-party, if so do manufrs. in Europe and Japan use that, or do all commission or design their own, is it designed and for sale in China, and do makes discussed in these forums already use that...

But my point in this thread (now, latterly) is, of course, that manufrs. simply do not like to divulge information on their mirror coatings. That is still unchanged.

Sorry the choice of CFD (wonderful stuff) in F1 for that comparison is not too clear to me. Not only the subject matter but surely also the programs are very different. Perhaps you only mean that F1 too have without difficulty moved to computer design and this is easier?
Personally I am not a fan of F1! It has too little relation to road cars, or to classic racing or rallying.
Adhoc

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Old Monday 14th May 2018, 10:19   #83
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Quote:
Originally Posted by adhoc View Post
Chosun,
Thanks for those links also.
Interesting to think: Is such software now available as third-party, if so do manufrs. in Europe and Japan use it, or do all commission or design their own, is it developed and for sale in China, and do makes discussed in these forums already use that...

But my point in this thread (now, latterly) is, of course, that manufrs. simply do not like to divulge information on their mirror coatings. That is still unchanged.

Sorry the choice of CFD (wonderful stuff) in F1 for that comparison is not too clear to me. Not only the subject matter but surely also the programs are very different. Perhaps you only mean that F1 too have without difficulty moved to computer design and this is easier?
Personally I am not a fan of F1! It has too little relation to road cars, or to classic racing or rallying. If one enjoys it per se then that is that.
Adhoc
Having said that, I'm not aware of any specific software available - only that writing the algorithms and code would not be too difficult - either in-house or by a third party. Given the amount of applications in so many various fields and products, it must exist as an off the shelf product. Similarly, everyone has some type of hydrophobic coatings ..... I doubt they all developed the same type of thing in isolation

Running computer simulations would be a lot quicker and easier than custom crafting each new prototype variation. Then it's just a matter of crunching the numbers to determine economic viability versus results given, and proving it up with a real prototype and manufacturing process.

I just mentioned the CFD since it is far more complex, and it is now employed as standard practice in both racing and production design development. Similar only in the analysis of an elemental component and then using the power of computers to crunch various integrations and iterations over various variable inputs.

I'm sure the 'individual coating recipes' are closely guarded secrets. That type of thing will never be released, but manufacturers will tout the number of layers, and each come up with their own trademarked catchphrase, even though a good number may simply be using exactly the same thing from the same supplier.

The technology of F1 has very close relation to production vehicles ... no maker can afford to blow ~$200 Million per annum just for the "fun" of going racing - it's all R&D and cross fertilization for the real world - it wouldn't be economically viable otherwise. I agree that while the current cars have a certain limited appeal in attaining 50%+ thermal efficiency, they are not a patch on the NA V10's @ 20,000 rpm !!


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Old Monday 14th May 2018, 11:40   #84
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Tringa45, post 81,
You are correct that the blackening of a silver surface is caused by a reaction with hydrogen sulfide, but that is still called oxidation since silver looses an electron and that is in our textbooks also called oxidation.
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Old Monday 14th May 2018, 12:02   #85
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Chosun, The history of road and racing interaction in tech development need not have gone this way. I wrote a bit on that in that last paragraph, posted it, then deleted it as too long for this forum. I will only(!) respond now that your rpm is a case in point. I (1) dislike and (2) fear rpm! No connection between 1 and 2. 1: I am not one who "thrills to the screams of tortured machinery". I want an engine to be firstly quiet. In sound and in movement. 2: Back in the day I tested power-on understeer in a front-w-d. car. It demonstrated that perfectly. Then the engine temp needle rose to the high-end mark. Utter panic and desperation. Till it was traced to a faulty wire connection! The memory remains. Today my old petrol pickup is seldom revved much beyond 2K on or off road.
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Old Monday 14th May 2018, 12:36   #86
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Quote:
Originally Posted by adhoc View Post
. Today my old petrol pickup is seldom revved much beyond 2K on or off road.
nothing to do with binos but i wish, i wish i were back in Oz cruisin' in my good old Hilux pickup. with binos behind the seat of course!
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Old Monday 14th May 2018, 12:59   #87
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Quote:
Originally Posted by adhoc View Post
Chosun, The history of road and racing interaction in tech development need not have gone this way. I wrote a bit on that in that last paragraph, posted it, then deleted it as too long for this forum. I will only(!) respond now that your rpm is a case in point. I (1) dislike and (2) fear rpm! No connection between 1 and 2. 1: I am not one who "thrills to the screams of tortured machinery". I want an engine to be firstly quiet. In sound and in movement. 2: Back in the day I tested power-on understeer in a front-w-d. car. It demonstrated that perfectly. Then the engine temp needle rose to the high-end mark. Utter panic and desperation. Till it was traced to a faulty wire connection! The memory remains. Today my old petrol pickup is seldom revved much beyond 2K on or off road.
Well ..... you're gonna love electric cars then !
(I don't know if I could bear this mortal coil without my 8&1/2 thousand rpm ride :) .......

Surely this stirs the soul though? ....
https://m.youtube.com/watch?v=eFNuQLcCIAY
Although this 1950's jobbie was apparently one to fear! (unless your name was Fangio :) ....
https://m.youtube.com/watch?v=fZMPDCNyQxE
https://m.youtube.com/watch?v=RBKUQPjQ16I

Race on Sunday -> sell on Monday has been going on just about since the auto's inception.

When the 'old man' Enzo Ferrari was asked what his favourite Ferrari was - he said, "the next one"



Chosun

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Old Monday 14th May 2018, 15:21   #88
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Jape,
Binocular behind the seat in a Hilux?
If the arm is moved between the seats then the console-plus-armrest,
or above the passenger seat (with no passenger!) then the headrest
surely get in the way? (I just tried it.)
Did this have neither? Have I got something wrong?
Thanks! (I like to learn new quick-draw techniques.)

Chosun,
Electric car. Of course. Ideal in every way.
If electricity generation when tracked back is clean enough.
Now a Tesla is one car where I would floor the pedal, if that is what you do in those.
But they are too big. (I await a small model and a large windfall.)
The 3 links. Wanton cruelty. Also self-humiliation.
Terrible unpleasant noises. And they are screaming (literally) out their inefficiency.
Are you serious? Okay then. Weltanschauung.
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Old Monday 14th May 2018, 16:48   #89
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Jape,
Binocular behind the seat in a Hilux?
.
well it was a surf dual cab 25yrs ago or so, and to be honest i didnt have binos back then, but would now. mind you the dog would have eaten them so the front door panel pocket would easily have been big enough for my 8x25s
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Old Tuesday 15th May 2018, 03:43   #90
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Originally Posted by adhoc View Post
....The 3 links ....
https://m.youtube.com/watch?v=eFNuQLcCIAY
https://m.youtube.com/watch?v=fZMPDCNyQxE
https://m.youtube.com/watch?v=RBKUQPjQ16I
Wanton cruelty .... Terrible unpleasant noises. And they are screaming (literally) out their inefficiency.
Are you serious? Okay then. Weltanschauung.
Lol. I prefer to think of the sound as an angelic symphony ..... but then, you know, "Weltanschauung"

Perhaps one of these might get the hairs standing on end ?
https://m.youtube.com/watch?v=OjwwV20iZYE
https://m.youtube.com/watch?v=ZBH3PZ18WtA
https://m.youtube.com/watch?v=eaRop_ZMwo0

If not, there's always electric cars .... and schinkenbrot !



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Old Wednesday 16th May 2018, 22:26   #91
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Originally Posted by Chosun Juan View Post
I think your conclusion is correct - the mirror is a silver based dielectric coating. We aren't of course privy to how many 'enhancement' layers on top of the protected silver coating it takes before it constitutes a dielectric coating.
So am I interpreting correctly that what Meopta are probably doing is applying a few layers of a dielectric coating onto the prism before topping it off with silver (and likely some protective sealing coating)?

It wouldn't make sense to have dozens of dielectric layers (as true dielectric coatings are understood to consist of) between the prism and the silver, as then the silver would not have any purpose anymore.
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Old Thursday 17th May 2018, 07:08   #92
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Mark9473, post 91,
On the basis of the mixed information or refusal to inform us in detail about the secrets of its mirror coatings we speculate a lot, but we do not know, since Meopta seems to consider it a company secret.
Looking at the improvement of the image quality over the past decade Meopta succeeded to make its binoculars competitive with other top quality binocular brands at a lower price level. It should make us happy users.
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Old Thursday 17th May 2018, 15:14   #93
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Meopta

Quote:
Originally Posted by Gijs van Ginkel View Post
Mark9473, post 91,
On the basis of the mixed information or refusal to inform us in detail about the secrets of its mirror coatings we speculate a lot, but we do not know, since Meopta seems to consider it a company secret.
Looking at the improvement of the image quality over the past decade Meopta succeeded to make its binoculars competitive with other top quality binocular brands at a lower price level. It should make us happy users.
Gijs van Ginkel


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