Yet, More on Collimation (1 Viewer)

WJC said:

.......

Finally, for most of my time in optics, 2 arc minutes was believed to be the best resolution the brain could discern. But recently, scientific tests with CRTs and cell phones have shown the we can detect resolutions down to 1 arc minute. A tiny amount, perhaps, but different by a factor of TWO! That is MORE than significant.

........

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Bill,

I really don't understand how that can be?

Herman Snellen in 1862 is usually credited with deciding that 2 arcsecond should be the threshold for normal visual acuity, as the majority of 'normal' people could achieve that or better it. The bottom line of the eye test chart that carries his name is usually 1 arcminute. Although that is commonly referred to as perfect vision, it's been understood for well over a century that this value can be exceeded, and binocular acuities as low as 36 arcsecons have been reported. Us Navy studies in the 1980s showed that their 'Top Gun' fast jet pilots frequently achieved 48 arcseconds. No CRTs or cell phones required. Just letter or other test charts suitably scaled.

David

typo said:

Bill,

I really don't understand how that can be?

Herman Snellen in 1862 is usually credited with deciding that 2 arcsecond should be the threshold for normal visual acuity, as the majority of 'normal' people could achieve that or better it. The bottom line of the eye test chart that carries his name is usually 1 arcminute. Although that is commonly referred to as perfect vision, it's been understood for well over a century that this value can be exceeded, and binocular acuities as low as 36 arcseconds have been reported. Us Navy studies in the 1980s showed that their 'Top Gun' fast jet pilots frequently achieved 48 arcseconds. No CRTs or cell phones required. Just letter or other test charts suitably scaled.

David

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191024

Oh, David, you’re such a pain. But not only am I going to let you live, I’ve changed the post in question and send you my sincere thanks. I may be considered a hardnose, but when corrected with pertinent facts, I bless my challenger. It was probably obvious to most who understood what I was trying to do. Even so, I thank you.

I have read most of the documents mentioned in post #7—onacounta I don’t have a life—at least the parts written on a third-grade level.

I am attaching a graphic to show a page of one of the military studies that shows the efforts put into some of these discussions. If you want to be pickier, you could also challenge my choice of Dr. B.K. Johnson’s thoughts for the alignment tolerances I accept for my own work. It was published by Dover Press in 1960. But testing by the Armstrong Aerospace Medical Laboratory was published in 1986, although testing was conducted in 1984-85. But then, Dr. Johnson's tolerances was originally published in 1948 ... or 1947, depending on which source is considered by the reader to be most dependable.

It should be noted there are differences in the tolerance data found in EACH of those studies. Who is right; who is wrong? E.B. White, of The Elements of Style Fame, wrote:

“I have yet to see a piece of writing, political or non-political, that does not have a slant. All writing slants the way the writer leans, and no man is born perpendicular.” :cat:

Cheers,

Bill

TXdefender said:

I'm near Houston, I was in law enforcement for 10yrs (hence the name) and used my binos on a daily basis, I've since quit doing that and am enjoying life even if the money isn't as good. I go to Lake Creek nature preserve and Spring Creek Greenway to do some nice observations but mostly I use my Binos in my neighborhood. We have wonderful species around here. Some favorites are the red shouldered hawk and we have a barred owls which are mostly heard but seldom seen. I love my Leica 7x42's and sometimes at night I can see the owls on overhead lines on my street. I use my Swaro spotting scope doing long range shooting and love it. I also participate in the sport which shall not be named on birdforum (sounds like shunting). I love and enjoy optics and it has always been a fascination of mine. I've enjoyed playing with my optics and always learning. I've gone from the complete novice to somewhat informed but would not consider myself near an expert like yourself. I've enjoyed reading your insights and expertise and hope to order your book as a Christmas present to myself. Keep up the good work Mr. Cook, I'm always willing to learn more.

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"Mr. Cook" was my dad. I'm just your garden variety "Bill."

I'm glad you like to learn. Please keep in mind that my BRILLIANCE is only surpassed by my ELEPHANTINE ... humility.

WJC said:

“At the time I left Captain’s in 2008, all collimation jobs returning from the European giants were well within tolerance as checked by me either with the Mk 5 or the Fujinon U.B.M.M.”

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Now that you've found reverse gear, you might want to revisit a couple of your previous assertions:

WJC said:

I have photographs of the CURRENT binocular collimator used by one of Europe’s “Big Three” and, although there are adjustments available, I see no way to take the axle into consideration.

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WJC said:

...I’m losing the warm fuzzies about today’s technicians even at the major optical firms knowing the in and outs of the operation. One senior tech told me they were only instructed in “how to get the alignment in the box.”

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WJC said:

Sadly, I’ve got the feeling they are leaving the most precise alignment to the spatial accommodation of the user, which I find a cost-saving but debilitating shortcut.

I have a photo of Gail Fisher (repair manager, now retired) at the collimator of Swarovski Optik USA and I see no way to consider the axle, which Dr. Hanna considered “the heart of the binocular.” And I just got the following from Zeiss the day before yesterday:

“Dear Sir
Anyone with this level of information at this point is probably long gone. You can check with either the Binocular Historical Society here in the US or the Optical Museum in Jena in Germany. Otherwise there is nobody of knowledge like this within the company to my knowledge.”

If people who have a real handle on binocular collimation are “probably long gone,” who’s running the railroad?

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WJC said:

At Captain’s, my 2 Navy Mk 5 collimators and Fujinon U.B.M.M. were always in plain sight of my customers and I was always eager to let customers take photos and show them exactly how they worked.

But then, I had nothing to hide. ‘Makes one think, doesn’t it?

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WJC said:

I checked every repair that was sent to the best companies. All were in 3-axis spec. But then, that was before the NO-FAULT madness started getting traction.

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What you are implying, or should I say the inference you intend the more credulous of your readership to draw - as it is extremely hard to credit that someone with your industry knowledge could honestly believe that the skill of proper collimation had vanished from "the major optical firms" - is pretty clear. I'm not at all sure you could get any of the publications you've written for to print them in their current form, and frankly, they deserve an apology. Which won't, of course, be forthcoming... as we both know, you would much rather rant and rail endlessly upon your pet topic. One can appreciate the sentiment behind said ranting and railing - most of us are threatened to a greater or lesser extent by consumerism and technology. But don't be surprised if proclamations as egregious as those above get called out.

Patudo said:

Now that you've found reverse gear, you might want to revisit a couple of your previous assertions:











What you are implying, or should I say the inference you intend the more credulous of your readership to draw - as it is extremely hard to credit that someone with your industry knowledge could honestly believe that the skill of proper collimation had vanished from "the major optical firms" - is pretty clear. I'm not at all sure you could get any of the publications you've written for to print them in their current form, and frankly, they deserve an apology. Which won't, of course, be forthcoming... as we both know, you would much rather rant and rail endlessly upon your pet topic. One can appreciate the sentiment behind said ranting and railing - most of us are threatened to a greater or lesser extent by consumerism and technology. But don't be surprised if proclamations as egregious as those above get called out.

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191024

Obviously, Patudo, I am wrong, but I never figured you for that sort.

I didn’t accuse anyone of anything. I stated reasonable suspicions based on valid observations and longevity in the field. Considering all the binocular forums I‘ve seen LIVE on opinions and speculations, I don’t think I need to apologize for any more than having an opinion that differs from your own. As stated in so many of my recent posts, I was just looking for answers—pure, simple, and worthwhile. Answers that would serve no purpose for me but which might interest others.

You have used MANY words—mostly mine. But for the benefit of the forum, why don’t you parse all that even more and state unequivalently exactly which statements you:

1. Say is a lie, or
2. State the opinions I don’t have the right to have.

I don’t wish to argue this further with you. I am the one who first contracted with Zeiss and was #1 on their list for out-of-warranty repairs and restoration. That bino in post #15 was sent to me on recommendations from Zeiss and Senior Chief Opticalman, Warren Nuckols—Zeiss USA repair manager—was a colleague. I am the one who first contracted with Leica. I am the one who increased Captain’s Swarovski sales by around 80%, earning the crystal Habicht from the company.

When you have been in the industry 10% as long as I have, sold 5% as many binos as I have, repaired and collimated 2% as many binos as I have (that’s about 240 units), and know as many optical engineers, optical educators, and manufactures as I have known, THEN we have reason to talk. Until then, you’re just looking for a fight that I will not accommodate.

If you are not willing to be specific in sharing EXACTLY wherein I have lied or EXACTLY wherein I have shared opinions that I DON’T HAVE THE RIGHT TO HAVE, I will just suggest that we “agree to disagree, agreeably.” For as I see it, without doing so you don’t have a leg to stand on, there is no wind in your sails, and your bucket has a hole in it.

Be specific and I will take the time to answer you as best I can. My request for you to have a great day was sincere ... and still goes.

I have heard from my big three contacts in the States. When I hear from those in Europe, I will share. :cat:

Cheers,

Bill

“The truth is incontrovertible. Malice may attack it, ignorance may deride it, but, in the end, there it is.” — Winston Churchill

Bill,

With regards to #22.

As a civilian scientist, I must say find the notion of having "optical constants for the standard eye" rather alien. There might be a gender bias in some of the values, but generally they seem in line with what I've found elsewhere, with the possible exception of the pupil diameter. That might be explained by some constraint explained elsewhere in the document. Of course there have been significant advancements in opthalmology since then which expand outr understanding of population diversity and move us even further away from the relevance of standardisation.

Some years ago, when I did have a hunt around for information on collimation tollerances, I think I found 4 sets of parameters, which may have included one or more of your list. I noted significant differences, but unfortunately don't remember the detail now. Much more relevant to most here is that from 2006 pretty much all civilian manufacturing has been regulated by the specifications contained in ISO14133-1, for "general purpose" binoculars and ISO14133-2 for "high quality" ones . I understand the ISO committee is formed of "recognised experts" and representatives of the major manufacturers from different countries. I personally think some of the other specifications are rather lax and I'm sure you might have views on the collimation standards below.

General purpose, magnifications 20x and under.
Dipvergence in the vertical plane. 30 arcminutes
Divergence in the horizontal plane. 100 arcminutes
Convergence in the horizontal plane. 40 arcminutes

High Quality, magnifications 20x or less
Dipvergence. 20 arcminutes
Divergence. 60 arcminutes
Convergence. 20 arcminutes

Unfortunately I can't tell you about the specified methodology and whether it is conditional or nor as I don't have the relevant ISO document.

David

typo said:

Bill,

With regards to #22.

As a civilian scientist, I must say find the notion of having "optical constants for the standard eye" rather alien. There might be a gender bias in some of the values, but generally they seem in line with what I've found elsewhere, with the possible exception of the pupil diameter. That might be explained by some constraint explained elsewhere in the document. Of course there have been significant advancements in opthalmology since then which expand outr understanding of population diversity and move us even further away from the relevance of standardisation.

Some years ago, when I did have a hunt around for information on collimation tollerances, I think I found 4 sets of parameters, which may have included one or more of your list. I noted significant differences, but unfortunately don't remember the detail now. Much more relevant to most here is that from 2006 pretty much all civilian manufacturing has been regulated by the specifications contained in ISO14133-1, for "general purpose" binoculars and ISO14133-2 for "high quality" ones . I understand the ISO committee is formed of "recognised experts" and representatives of the major manufacturers from different countries. I personally think some of the other specifications are rather lax and I'm sure you might have views on the collimation standards below.

General purpose, magnifications 20x and under.
Dipvergence in the vertical plane. 30 arcminutes
Divergence in the horizontal plane. 100 arcminutes
Convergence in the horizontal plane. 40 arcminutes

High Quality, magnifications 20x or less
Dipvergence. 20 arcminutes
Divergence. 60 arcminutes
Convergence. 20 arcminutes

Unfortunately I can't tell you about the specified methodology and whether it is conditional or nor as I don't have the relevant ISO document.

David

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191025

Of course, Typo, what is “Standard;” what is “Average”? We all use the terms but, in the REAL world, they are all pretty close to useless. Perhaps it would be slightly better to say “median, of those tested.” Total precision would dictate that rods and cones be of the same number, length, and sensitivity and the physiological processing be exactly the same in all test subjects—good luck with that. This means that “total precision” is out of the question. Thus, E.B. White’s take on the matter, in post 22, applies.

I take the findings of the Armstrong Aerospace Medical Research Laboratory into account, which in May of 1986 revealed in part:

“Indeed, a degree of alignment error unnoticed by, or even undetectable by, one observer may be unacceptable to another.”

and

The survey further cited, “Zero optical tolerances and zero tolerances for image differences are not practical: they would be too difficult and expensive to obtain and could not be retained in use.”

I find your data on current ISO “standards” to be most helpful. But interested parties should recognize that had the test subjects been different the PUBLISHED RESULTS would have been different as well. Which would have been most correct?

The EXPERTS who wrote the Chicago Manual of Style and the EXPERTS who wrote the Associated Press Stylebook differ in how one should use or not use the Oxford/serial Comma.

They didn’t give Socrates the option of “picking his poison.” We are not so constrained. :cat:

Cheers,

Bill

PS Sorry to be misunderstood and cause such a ruckus. But if the Wright brothers hadn't rocked the boat ... we would still be taking it to London.

Bill,

Standard or average is next to useless in this type of application as half the population might be automatically excluded. With a normal population distribution, +/- two standard deviations would cover 95% of the population, and three SDs about 99%.

David

typo said:

Bill,

Standard or average is next to useless in this type of application as half the population might be automatically excluded. With a normal population distribution, +/- two standard deviations would cover 95% of the population, and three SDs about 99%.

David

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David,

Isn’t that what I said in my first sentence, above?

Also, check out the uselessness of the graphic recently captured on Cloudy Nights—attached. Someone wanted a definitive answer to a question with an endless number of variables. Most of these people are intelligent and sincere. However, what they don’t understand about optics, binoculars, and the binocular industry renders their question as useless as a steering wheel on a stone. :cat:

Bill

WJC said:

.....
.....
.....
..... as useless as a steering wheel on a stone.

Bill

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A steering wheel on a stone is useless??? :eek!: Can you prove that??

WJC said:

David,

Isn’t that what I said in my first sentence, above?
.....

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Not in the first, possibly in the second, but then contradicted in the third. Just trying to clarify stuff.

David

typo said:

Not in the first, possibly in the second, but then contradicted in the third. Just trying to clarify stuff.

David

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191026

If I were a class act, which you all know I’m not, I would let this tag-teaming roll off like water of a duck’s back. But protecting my credibility that I still might help others; I have to address some things.

Canip wrote: A steering wheel on a stone is useless??? Can you prove that??

I sure can. I refer you to the Steering Wheel on a Stone Project, USA-MP-7113.18, Oct 11, 1942—May 31, 1944, conducted by the Ford Motor Company and fully funded by the US government.

In this project, stones of various sizes were tested with the most viable being the crew-cab versions which weighed in at 25-35 pounds. Even so—and filmed—there was no recorded alterations in movement. Reporters from CNN cried foul saying the stones had not been outfitted with wheels on the undercarriage. Government officials countered with evidence that they were prepared to dump millions more into the project once any one of the test stones showed signs of changing course. This bickering came to a halt early in May of 1944 when Henry Ford announced his company needed additional space for the development of the Edsel.

For a time, workers were in a panic; none had ever held real jobs. But after working odd jobs for years, they all gained lucrative employment. Some were hired to substantiate Obama Care before the American people while others took jobs in the UK trying to UN-substantiate BREXIT.

.............. Canip, you turkey!

Typo: In post #28, you said

Standard or average is next to useless in this type of application as half the population might be automatically excluded.

Yet, in the post before, #27, I said

Of course, Typo, what is “Standard;” what is “Average”? We all use the terms but, in the REAL world, they are all pretty close to useless.

From my vantage point, those two statements say virtually the same thing.

As far as being contradictory, the only possibility would have been in comments made by the physicians and engineers of the Armstrong Aerospace Medical Laboratory—MDs and PhDs all—over which I had no control. :cat:

Cheers,

Bill

WJC said:

When you have been in the industry 10% as long as I have, sold 5% as many binos as I have, repaired and collimated 2% as many binos as I have (that’s about 240 units), and know as many optical engineers, optical educators, and manufactures as I have known,

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...so, with all that experience and industry knowledge, you either:

(a) have come to believe that companies like Swarovski and Zeiss - whose businesses depend on manufacturing top tier optics - have either lost, or dispensed with the process of three-axis collimation, or;

(b) know better, but via statements such as "I have photographs of the CURRENT binocular collimator used by one of Europe’s “Big Three” and, although there are adjustments available, I see no way to take the axle into consideration." and "If people who have a real handle on binocular collimation are “probably long gone,” who’s running the railroad?", are inviting your readership to think otherwise?

...readers can draw their own conclusions... :cat:

WJC said:

I have heard from my big three contacts in the States. When I hear from those in Europe, I will share.

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Please do. :cat:

Patudo said:

...so, with all that experience and industry knowledge, you either:

(a) have come to believe that companies like Swarovski and Zeiss - whose businesses depend on manufacturing top tier optics - have either lost, or dispensed with the process of three-axis collimation, or;

(b) know better, but via statements such as "I have photographs of the CURRENT binocular collimator used by one of Europe’s “Big Three” and, although there are adjustments available, I see no way to take the axle into consideration." and "If people who have a real handle on binocular collimation are “probably long gone,” who’s running the railroad?", are inviting your readership to think otherwise?

...readers can draw their own conclusions... :cat:


Please do. :cat:

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Patudo, you still seem eager for the fight I will not accommodate. I truly believe if you had the whole picture, you would not be so confrontational. Have I given you reason to believe I am not trustworthy? If I haven’t, I would ask that you trust me. I know you don’t like my method of communication—you are not alone. However, it has its place in what I strive to do. On Wednesday, I will be sending a letter to all three of the big three companies. Stating, EXACTLY, my thinking and asking for their reply. Each knows (although you don’t, having entered the play during the last part of the second act) I have been a supporter since first entering the profession. And I believe, based on what I know, they will see my query as justified. All they would need do is just tell me what you profess to know so undeniably. I believe you are correct. As of September 2008—as clearly stated in post #17—I know you were. I checked; something most optical retailers don’t have the interest or wherewithal to do.

I believe those reading (and reasoning) my original comments would see I had valid reasons for my suspicions and that I was not accusatory as you continue to imply. More often than not our understanding rests with the magnitude of our humble willingness to understand. All I’m asking you to do is just be that humble for just a few days more. :cat:

Bill

Bill,

I understand your emphasis on proper collimation of binoculars but the exchanges have become too verbose and too personal at this time to be useful for a person that wants to understand the topic. I'll try to summarize your argument to make sure the readers understand your arguments correctly:

Summary of Bill's points:

a) It is important to collimate binoculars at all IPD positions so that the two barrels have perfectly parallel optical axis. This is called three-axis collimation.

b) To save time or cost or due to poor knowledge, even the premium European companies don't do this. This is inferred by looking at their collimator equipment and other anecdotal evidence.

c) As a result, it is possible that some image viewing issues or discrepancies observed by various users of premium binoculars are due to poor collimation rather than primary aberrations of the optical system.

Is the above summary accurate?

-Omid

Omid said:

Bill,

I understand your emphasis on proper collimation of binoculars but the exchanges have become too verbose and too personal at this time to be useful for a person that wants to understand the topic. I'll try to summarize your argument to make sure the readers understand your arguments correctly:

Summary of Bill's points:

a) It is important to collimate binoculars at all IPD positions so that the two barrels have perfectly parallel optical axis. This is called three-axis collimation.

b) To save time or cost or due to poor knowledge, even the premium European companies don't do this. This is inferred by looking at their collimator equipment and other anecdotal evidence.

c) As a result, it is possible that some image viewing issues or discrepancies observed by various users of premium binoculars are due to poor collimation rather than primary aberrations of the optical system.

Is the above summary accurate?

-Omid

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Omid,

It is partially accurate.

Some clarification;

1. When one is taken to task for something he didn’t do, verbosity—by way of thorough explanation—can be useful.

2. Both telescopes need to parallel to the MECHANICAL AXIS (the axle) AS WELL.

3. I didn’t ACCUSE the Big Three of anything. I just shared honest observations that at least one took as accusatory. I pointed out that as of September 2008 things were as the should be but much has happened since then. I plainly stated I was just looking for facts and revealed some of the reasons for doing so. You may also note—through the previous post—that I have rejected the unfounded need to be confrontational.

I would have assumed that one of the European giants (in the US) could have answered my simple questions. Alas, no.

I have gotten information from two of these giants and when I get a letter from the third, I will make the contents known. I haven’t written that letter yet, as I have been on my back for the last 3 days with intestinal problems. :cat:

Bill

While I have not heard from Swarovski, I am struggling to get a book out and I must put this thing behind me for now. Lee has an “in” with the big Z and has sent me the following memo:

Hi Bill

just received response from my pal at Zeiss who replies that all their collimators are supplied by their engineering dept and checked by the quality assurance dept but he is not allowed to share drawings or manuals.

However I think Gary's response tells you what you want to know about Zeiss and Leica even if it doesn't explain why some other places don't use 3 axis method.

Like Lee, I have long-trusted Gary and I found his comments valuable. I thought I had made my reasons for wondering amply clear and that I was just QUESTIONING but never ACCUSING. And I stated that I knew, empirically, 3-axis collimation was being carried out as late as September 2008.

Thus, the idea that the Big Three might be taking shortcuts based on hammered sales or new scientific data regarding spatial accommodation in the collimation process, has been taken off the table as well as having been taken WAY out of context.

If I might be so bold as to offer another query—which I think I have a right to—it would be in wondering why I was eager to show my customers my collimators and process and some Asian firms show row after row of techs sitting at Fujinon U.B.M.M.s, while others are so secretive about their equipment and process. Is that not a logical question to ask?

One possible reason is that they have developed some PROPRIETARY equipment or techniques that they feel it important to keep from the competition.

— I know for a FACT that some prominent American binocular importers and individual techs are unfamiliar with spatial accommodation and 3-axis collimation and call their unscientific, sometimes damaging, willy-nilly alignment process, “collimation.” In addition, I don’t think the average European alignment technician has any more knowledge of the subject than our guys. (Please ask Cory Suddarth of Suddarth Optical Repair, https://suddarthoptical.com/)
— I know for a FACT that 100% of the collimation tips CURRENTLY found on the Internet deal only with conditional alignment and not clinical collimation—although novice alignment techs ubiquitously refer to it as such.
— I know for a FACT that until I explained the difference between collimation and conditional alignment to the optical engineers of SPIE and the UA’s College of Optical Sciences in 2012, they were unaware of the importance. It was NOT a matter of ignorance or indifference. It was just something that was out of the realm of their training and everyday thinking. At that level of understanding, knowledge of Optics and Mechanics diverge, with collimation falling under the umbrella of Mechanics.

I have always been eager, for the benefit of the science, to fall on my sword when PROVEN wrong. I have also been resolute in standing my ground when needlessly challenged by those lacking some portion of facts and motivations. :cat:

WJC said:

Thus, the idea that the Big Three might be taking shortcuts based on hammered sales or new scientific data regarding spatial accommodation in the collimation process, has been taken off the table...

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... a retraction as timely as it was warranted. :cat:

Patudo said:

... a retraction as timely as it was warranted. :cat:

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Patudo:

There was NO retraction: nor was a retraction warranted!

And I try not to say things for which one will ever be needed. I drew LOGICAL conclusions based on plausible POSSIBILITIES for which I sought answers. For me? Nay. I hope to help others over so many of the poorly contrived—and frequently wrong—opinions that can strangle the honest truth seeker.

When I am PROVEN wrong on something, my track record has ALWAYS been to admit it and be pleased for it that I might steer others in a better direction.

If you were to take the time to go over all I have said, you would see you had jumped to conclusions concerning accusations—that never happened—without all the facts. But then, that is what bino forums are largely about, isn’t it?

For me to help others, my reputation must remain intact. So, if I seem unduly resolute, that is the reason. I maintain we are all products of our knowledge and experiences and I can assure you that four and a half decades in the optical industry—associating with engineers, academics, manufacturers, technicians, importers, and retailers—has given me a perspective to which you may never be privy.

Talk is cheap; having the goods is better. :cat:

Still wishing you a pleasant day—whether you need it or not,

Bill

Would be entertaining to bring a number of bins along for an afternoon with a collimator, measure the degree of alignment and see how we get on. Old stuff, new stuff, Porro, roof... get some stats. Drop some, remeasure, see how robust they are....
“ I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind.”... Lord Kelvin.

PEter