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Bino Thoughts #3 (1 Viewer)

WJC

Well-known member
Bino Thoughts #3

I know I’m a fellow who bellyaches about those who stack BBs and talk forever about things that are inconsequential to most observers. Even so, having experienced what I have, I must stack a few BBs here. Please forgive me.

Reading a thread currently on the forum, one could come away with the idea that you just set and forget the DIOPTER setting. There is, however, something more to be said. Not to MOST birders, or long-time binocular users, but not all new observers fit into those categories.

1. I guess DIOPTER adjustment sounds cooler. But it is nothing more than another name for a FOCUS MECHANISM. The center wheel on a center-focus binocular is never looked at as a diopter adjustment. But that’s exactly what it is. Does it focus one eye, usually the left? Then it is a diopter adjustment. Please see attachment #1.

2. Auto-focus binoculars are a misleading marketing ploy with many advertisers buying into the concept. And PERMA-FOCUS is just another scam to get money from the terminally trusting and massively inexperienced consumer. There is no such thing as a non-electronic auto-focus binocular. * These binoculars depend on the stretching or compressing of the eyelens via the ciliary muscles (attachment #2) to focus the image. Thus, the binocular does nothing. It is not somehow magic and does not defy the laws of physics. It forces your eyes to focus ... at least if you are young enough. (attachment #3) This can cause a little or a lot of eyestrain and causes the observer who hasn’t learned to stare to keep wasting time fiddling with the focus.

3. Most birders know that IF (individual focus) binoculars are the bane of enjoyable bird watching. However, someone new to BirdForum and using an individual focus binocular could come away with very wrong information as BOTH diopter rings must be adjusted for each DISTANCE observed.

Finally,

4. The center wheel or flip-lever on a center focus binocular focuses BOTH sides. If you have adjusted the right eye—correctly, after focusing the left eye at a given distance—that won’t matter as the diopter for the right eye will keep your correction in sync as you change your observing distance with the center wheel or flip-lever.

5. Now for the BB stacking caveat. While the diopter setting will usually get you into a focus that causes no severe eyestrain. The nitnoids in our group may want to know that there is no perfect focus. Focus will change with fatigue, headaches, alcohol use, caffeine use, prescription drug use, or too much or too little water in the system. Is that something to worry about? Only if you are one of those people who can’t function without something inconsequential to worry about.

See ... something for everyone. :cat:
 

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StephenHampshire

Well-known member
United Kingdom
Bino Thoughts #3

I know I’m a fellow who bellyaches about those who stack BBs and talk forever about things that are inconsequential to most observers. Even so, having experienced what I have, I must stack a few BBs here. Please forgive me.

Reading a thread currently on the forum, one could come away with the idea that you just set and forget the DIOPTER setting. There is, however, something more to be said. Not to MOST birders, or long-time binocular users, but not all new observers fit into those categories.

1. I guess DIOPTER adjustment sounds cooler. But it is nothing more than another name for a FOCUS MECHANISM. The center wheel on a center-focus binocular is never looked at as a diopter adjustment. But that’s exactly what it is. Does it focus one eye, usually the left? Then it is a diopter adjustment. Please see attachment #1.

2. Auto-focus binoculars are a misleading marketing ploy with many advertisers buying into the concept. And PERMA-FOCUS is just another scam to get money from the terminally trusting and massively inexperienced consumer. There is no such thing as a non-electronic auto-focus binocular. * These binoculars depend on the stretching or compressing of the eyelens via the ciliary muscles (attachment #2) to focus the image. Thus, the binocular does nothing. It is not somehow magic and does not defy the laws of physics. It forces your eyes to focus ... at least if you are young enough. (attachment #3) This can cause a little or a lot of eyestrain and causes the observer who hasn’t learned to stare to keep wasting time fiddling with the focus.

3. Most birders know that IF (individual focus) binoculars are the bane of enjoyable bird watching. However, someone new to BirdForum and using an individual focus binocular could come away with very wrong information as BOTH diopter rings must be adjusted for each DISTANCE observed.

Finally,

4. The center wheel or flip-lever on a center focus binocular focuses BOTH sides. If you have adjusted the right eye—correctly, after focusing the eye at a given distance—that won’t matter as the diopter for the right eye will keep your correction in sync as you change your observing distance with the center wheel or flip-lever.

5. Now for the BB stacking caveat. While the diopter setting will usually get you into a focus that causes no severe eyestrain. The nitnoids in our group may want to know that there is no perfect focus. Focus will change with fatigue, headaches, alcohol use, caffeine use, prescription drug use, or too much or too little water in the system. Is that something to worry about? Only if you are one of those people who can’t function without something inconsequential to worry about.

See ... something for everyone. :cat:

I enjoy your posts Bill: I have a mental picture of you and I'm not sure we'd see eye to eye (pun intended) on some of the more political issues that get mentioned on this forum sometimes, but you are spot on on this one. As I get tired/dehydrated, or as the light fades and my pupils open up,my left and right eyes definitely diverge more! Dioptre fiddling and eye placement become "de rigeur". I have astigmatism in my right eye which makes bino use without glasses a bit tricky, but I also use varifocals which can be interesting! Steve
 

pbjosh

missing the neotropics
Switzerland
5. Now for the BB stacking caveat. While the diopter setting will usually get you into a focus that causes no severe eyestrain. The nitnoids in our group may want to know that there is no perfect focus. Focus will change with fatigue, headaches, alcohol use, caffeine use, prescription drug use, or too much or too little water in the system. Is that something to worry about? Only if you are one of those people who can’t function without something inconsequential to worry about.

See ... something for everyone. :cat:

I've only recently noticed the real world effect of this in a binocular. For whatever reason - my accommodation + poor vision + poor quality standards, or whatever it may be, I've typically been someone to set the diopter once and forget it. However I have a bin with "finicky" focus and "poor depth of field" or at least so I have perceived it. Based upon what I can observe + what more knowledgeable folks comment about this particular model, I feel that this is due to a quite curved field of view combined with quite a bit of distortion/aberration. In any case, this particular binocular definitely benefits from adjusting the diopter depending on fatigue / state of drunkenness / whatever the case may be. Just as the center focus is finicky, the diopter is as well. Said binocular is ever less preferred among my humble collection and will get sold on at some point.
 

StephenHampshire

Well-known member
United Kingdom
I've only recently noticed the real world effect of this in a binocular. For whatever reason - my accommodation + poor vision + poor quality standards, or whatever it may be, I've typically been someone to set the diopter once and forget it. However I have a bin with "finicky" focus and "poor depth of field" or at least so I have perceived it. Based upon what I can observe + what more knowledgeable folks comment about this particular model, I feel that this is due to a quite curved field of view combined with quite a bit of distortion/aberration. In any case, this particular binocular definitely benefits from adjusting the diopter depending on fatigue / state of drunkenness / whatever the case may be. Just as the center focus is finicky, the diopter is as well. Said binocular is ever less preferred among my humble collection and will get sold on at some point.

@Pigbin Josh -drunkeness can make spotting aliens tricky even with good binos;)
 

WJC

Well-known member
I've only recently noticed the real world effect of this in a binocular. For whatever reason - my accommodation + poor vision + poor quality standards, or whatever it may be, I've typically been someone to set the diopter once and forget it. However I have a bin with "finicky" focus and "poor depth of field" or at least so I have perceived it. Based upon what I can observe + what more knowledgeable folks comment about this particular model, I feel that this is due to a quite curved field of view combined with quite a bit of distortion/aberration. In any case, this particular binocular definitely benefits from adjusting the diopter depending on fatigue / state of drunkenness / whatever the case may be. Just as the center focus is finicky, the diopter is as well. Said binocular is ever less preferred among my humble collection and will get sold on at some point.

The diopter IS a focus mechanism. Also, most people seeing DISTORTION label it as CURVATURE of field. :cat:

Cheers,

Bill
 
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Anon2020

Active member
Interesting thoughts on dioptre adjustment however my optician assures me that I and most people have a dominant eye and in my case certainly I don’t feel the need to make constant adjustments as I do tend to view predominantly through one eye. This is not a conscious habit and begs the question why use binoculars instead of a monocular.

I do however find that binoculars give a much easier view notwithstanding my observations above.
 

StephenHampshire

Well-known member
United Kingdom
Interesting thoughts on dioptre adjustment however my optician assures me that I and most people have a dominant eye and in my case certainly I don’t feel the need to make constant adjustments as I do tend to view predominantly through one eye. This is not a conscious habit and begs the question why use binoculars instead of a monocular.

I do however find that binoculars give a much easier view notwithstanding my observations above.

I'm strongly left eye dominant which makes using some cameras with viewfinders difficult. I will admit to sometimes using only the left barrel of binoculars when focusing on a butterfly or flower close to the minimum focus distance
 

WJC

Well-known member
Interesting thoughts on dioptre adjustment however my optician assures me that I and most people have a dominant eye and in my case certainly I don’t feel the need to make constant adjustments as I do tend to view predominantly through one eye. This is not a conscious habit and begs the question why use binoculars instead of a monocular.

I do however find that binoculars give a much easier view notwithstanding my observations above.

Hi, Anon2020,

We ALL have a dominant eye. That does not preclude the benefits of using a binocular. I find that some don’t explain themselves very well, are not understood very well, or need to spend more time with precision—as opposed to ophthalmic—optics. Please see the attached. :cat:

Bill
 

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tenex

reality-based
1. I guess DIOPTER adjustment sounds cooler. But it is nothing more than another name for a FOCUS MECHANISM. The center wheel on a center-focus binocular is never looked at as a diopter adjustment. But that’s exactly what it is. Does it focus one eye, usually the left? Then it is a diopter adjustment.
What on earth does this mean? A center-focus wheel focuses both tubes at once, that's the whole point. On most binoculars that's all it can physically do (on some it has another mode). As so often, you're making something very simple unnecessarily confusing, typically creating misunderstandings by anticipating them, though in this case I can't even guess.
 

Pinewood

New York correspondent
United States
Bino Thoughts #3

...
5. Now for the BB stacking caveat. While the diopter setting will usually get you into a focus that causes no severe eyestrain. The nitnoids in our group may want to know that there is no perfect focus. Focus will change with fatigue, headaches, alcohol use, caffeine use, prescription drug use, or too much or too little water in the system. Is that something to worry about? Only if you are one of those people who can’t function without something inconsequential to worry about.

See ... something for everyone. :cat:

Hello Bill,

Many years, ago, when I purchased a new binocular, I actually read the instructions. I was instructed to find something in the middle distance, 6m?, then focus on it with my left eye, with my right eye closed. Then adjust the dioptre setting with right eye while my left I was close. [I believe that you favour covering the objective*]
From those instructions, I inferred that the dioptre might need an adjustment at the extremes of the focussing range for optimal use. However, I guess that worrying about that, for most with reasonable accommodation, is rather like stacking BB's.
When I use an IF binocular, as for astronomy, I do tend to fiddle more.

Stay safe,
Arthur
*Some people do read your posts.
 

pbjosh

missing the neotropics
Switzerland
The diopter IS a focus mechanism.

Of course it is. But calling it a focus mechanism is less specific and I would suggest purposefully obfuscating / confusing.

"When I'm tired I find that just adjusting the focus isn't enough, I also have to adjust the focus mechanism. I thought I'd set the focus prior, but upon focusing, realized that I hadn't focussed."

That's not a particularly useful way to communicate.
 

WJC

Well-known member
What on earth does this mean? A center-focus wheel focuses both tubes at once, that's the whole point. On most binoculars that's all it can physically do (on some it has another mode). As so often, you're making something very simple unnecessarily confusing, typically creating misunderstandings by anticipating them, though in this case I can't even guess.

You are certainly correct. But you are reading faster than reasonable. I am trying to drag people out from under all the BS that’s out there and MAKING things more complicated than need be trying to keep up with the EXPERTS.

In 4) I said:

4. The center wheel or flip-lever on a center focus binocular focuses BOTH sides. If you have adjusted the right eye—correctly, after focusing the left eye at a given distance—that won’t matter as the diopter for the right eye will keep your correction in sync as you change your observing distance with the center wheel or flip-lever.

Under the misgivings out there, I have to say MORE THAN SHOULD BE NECESSARY just to unscrew the screwups from EXPERTS.

Please learn WHY before finding fault with the HOW. See Attached. :cat:

Bill
 

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John A Roberts

Well-known member
Australia
As a field expedient to placing an objective cap over one binocular barrel while focusing the other, as is shown in Bill's attachment to post #12:
just lower the non-focus barrel around 1/2" (or around 15 mm), while keeping the focusing barrel aligned with the pupil of the other eye

Since a binocular exit pupil is typically 7 mm at most, the EP of the lowered barrel will no longer be in line with the eye,
and so the eye will be looking at a blurred field, while remaining open and relaxed


John
 

WJC

Well-known member
As a field expedient to placing an objective cap over one binocular barrel while focusing the other, as is shown in Bill's attachment to post #12:
just lower the non-focus barrel around 1/2" (or around 15 mm), while keeping the focusing barrel aligned with the pupil of the other eye

Since a binocular exit pupil is typically 7 mm at most, the EP of the lowered barrel will no longer be in line with the eye,
and so the eye will be looking at a blurred field, while remaining open and relaxed


John

But John, Please realize that was written by the acknowledged experts, not me. :cat:

Bill
 

WJC

Well-known member
Of course it is. But calling it a focus mechanism is less specific and I would suggest purposefully obfuscating / confusing.

"When I'm tired I find that just adjusting the focus isn't enough, I also have to adjust the focus mechanism. I thought I'd set the focus prior, but upon focusing, realized that I hadn't focussed."

That's not a particularly useful way to communicate.

pbjosh:

I don’t know who said, "When I'm tired I find that just adjusting the focus isn't enough, I also have to adjust the focus mechanism. I thought I'd set the focus prior, but upon focusing, realized that I hadn't focussed." But it certainly wasn’t me. [Also, the Delete and Quotation keys are out on my keyboard; another is coming.]

My approach is difficult and two-fold. I want to give people something REALISTIC to believe at the same time I’m telling them about so much of the popular, but erroneous, information placed before them. When I seem confusing, it is almost always because of things my detractors do not, cannot, or will not take into consideration. It is so much easier to misunderstand and lash out without reasonable provocation than it is to do a little research and communicating.

If you and Tenex would like to do a service for the American reader, you might want to tell the editors of Sky & Telescope, ASTRONOMY magazine, National Wildlife, Sea History, Times of the Islands, Proceedings magazine (SPIE publication), Lattitudes & Attitudes, and several dozens other publications that Bill Cook can’t write clearly and should not be allowed to confuse their readers.

And this month, it was Lattitudes & Attitude (Cover Story on binoculars) before that it was Times of the Islands (Cover Story on birding and binoculars). Then there’s the comment on my UNMATCHED WRITING STYLE from Gail Fisher, manager of the repair department For Swarovski Optik USA. But hey, what would a Swarovski manager know about writing and optics? And while I’m at it, please let me point out that for 18 years, I was Zeiss USA's go-to guy for out of warranty optical repair—until I had a stroke and left Captains.

No, Lee, I don’t need to cool down. I’m just trying to buy myself a little time between ill-conceived attacks from those who don’t know the whole story. I know I say things that are often not popular. However, I am ALWAYS available to explain myself ... IF ASKED. Sadly, the questions often come in the form of accusations. I have been able, over the last many years, to correct several long-standing misgivings. It has not been done without cost. I realize, as I try to get my repair business off the ground, I am supposed to treat everyone with a sickly sweet—disingenuous—demeanor. However, If I were willing to bend the truth for the dollar, I would be a wealthy optics mogul, today. :cat:

Without health you HAVE nothing; without integrity you ARE nothing.

Bill
 

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Anon2020

Active member
Can you translate “BB”? I hardly think it is an abbreviation of any of the expressions my quick Google search brought up - Brigitte Bardot? Battleship? Big Bertha?

Without in any way wishing to disparage any of the observations/arguments made above it does seem to me somewhat ironic that the apparent criticism of experts is being made by someone who on the face of it is purporting to be an “expert” themselves.
 

Ries

Well-known member
What is a BB?

If you're replying on a thread, couldn't you just have posted a reply with your no. 4 point in there? That would've been useful on a useful place.
 
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Troubador

Moderator
Staff member
Supporter
Richard and Anon, I believe Bill means BB to be short for ball-bearings, hence his references to trying to stack them.

Lee
 

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