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Dodgy vision or Binocular fault? (1 Viewer)

Bluben79

Member
United Kingdom
Apologies if this a is a totally stupid question.

I have a pair of Viking Badger binoculars that I've had for a short time as my first pair of Binoculars. I can get a clear image in the centre when looking through but I can't get both barrels to make a one circle (does that make any sense?)

I don't think its a collimation issue as the centred image is in perfect focus but I see double rings on the outside of the image. I called Viking and they said it may be an issue with the focusing rods. I don't really want to send them back if its me being a total wally and I haven't adjusted something correctly. Any ideas?

I'm not sure if this could be a vision issue. I have a strong left eye dominance, don't know if this may have a bearing.
 

Troubador

Moderator
Staff member
Supporter
Can you see all the objects in the view, each with only a single in-focus image or does each consist of two images very close to each other that do not perfectly overlap? Have you tried adjusting with the hinge of the binos so that the eyepieces move closer together or further from each other. Doe this allow you to merge the two image circles into one?

Lee
 

Bluben79

Member
United Kingdom
Can you see all the objects in the view, each with only a single in-focus image or does each consist of two images very close to each other that do not perfectly overlap? Have you tried adjusting with the hinge of the binos so that the eyepieces move closer together or further from each other. Doe this allow you to merge the two image circles into one?

Lee
There's definitely not two images. The best way I can describe it is to say if you had two semi circles and put them together to make a circle but the edges on the two semi circles didn't quite meet with one slightly higher than the other. No amount of adjustment seems to fix this.
 

Foss

Well-known member
Hey Bluben79. If you turn the binoculars upside down, (looking thru the left EP with your right eye, etc.) does the semi-circle overlap change sides too? If so, could be a sign it's the binos. ~ Foss
 

Troubador

Moderator
Staff member
Supporter
There's definitely not two images. The best way I can describe it is to say if you had two semi circles and put them together to make a circle but the edges on the two semi circles didn't quite meet with one slightly higher than the other. No amount of adjustment seems to fix this.
Sounds like the binos are out of collimation.
Lee
 

WJC

Well-known member
Apologies if this a is a totally stupid question.

I have a pair of Viking Badger binoculars that I've had for a short time as my first pair of Binoculars. I can get a clear image in the centre when looking through but I can't get both barrels to make a one circle (does that make any sense?)

I don't think its a collimation issue as the centred image is in perfect focus but I see double rings on the outside of the image. I called Viking and they said it may be an issue with the focusing rods. I don't really want to send them back if its me being a total wally and I haven't adjusted something correctly. Any ideas?

I'm not sure if this could be a vision issue. I have a strong left eye dominance, don't know if this may have a bearing.
Collimation and focus are two different animals. Also, keep in mind that a collimation error that would cause one person to go bonkers might not be noticed by another.

Anytime a bino came to me for repair or collimation, my initial routine didn’t vary: I checked the axle and then collimation. One day, a lady came in to have me clean her objectives. Looking out the front door, I saw a van in the parking lot ... or should I say, “two vans in the parking lot”?

Returning to the customer, I pointed out that the bino was out of collimation dozens of times more than the maximum allowable error... for ANYONE. Her reply, “Well, it looks okay to me.” Was she lying? Was she stupid? Was she seeing with her dominant eye, only? Or was she inexperienced and unaware of what she SHOULD be seeing?

Can’t happen?! Another time, a well-dressed, well-groomed, articulate and educated fellow brought his binocular in because no matter what he did, he couldn’t get, “the PROPER figure-eight picture.”

It seems some people think binoculars are baked by elves in a hollow tree.

Bill
 

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pat mitchel

Well-known member
How bout you confer with another person looking through the same binos and ask what they perceive. Better yet find another bino user and ask if you can try their bino to see if the fault lies within... Regards, Pat
 

Mark9473

Well-known member
Belgium
In 44 years of using various binoculars, I've never seen a perfect single circle as the combined FOV. My right eye has a different correction than the left eye, as I found out in my early 40's when I suddenly needed reading glasses. But I still don't use glasses when looking through binoculars.
 

jring

Well-known member
Hi,

the tricky part with seeing collimation problems in binoculars is that the brain is able to merge a certain degree of misalignment... if it's a bit more, you might get a headache over time, but not really see a double image...

One can either try to fool the brain by keeping one eye closed and then opening it again - one might see a double image for a short time until the brain adapts again.

A better way needs a clear sky at night - search for a bright star and then turn the diopter setting to the limit, so you get a big faint disk instead of a bright star for that tube... since the brain doesn't see a star in that tube any more, it doesn't try to merge the images and thus you can see whether the white point is in the middle of the faint disk, or not.

Joachim
 
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WJC

Well-known member
Hi,

the tricky part with seeing collimation problems in binoculars is that the brain is able to merge a certain degree of misalignment... if it's a bit more, you might get a headache over time, but not really see a double image...

One can either try to fool the brain by keeping one eye closed and then opening it again - one might see a double image for a short time until the brain adapts again.

A better way needs a clear sky at night - search for a bright star and then turn the diopter setting to the limit, so you get a big faint disk instead of a bright star for that tube... since the brain doesn't see a star in that tube any more, it doesn't try to merge the images and thus you can see whether the white point is in the middle of the faint disk, or not.

Joachim

There are as many tolerance guides for collimation as there are experts on lens cleaners. Attached (page 95 in that book I'm not allowed to mention) is the one I choose to use.

Bill

scan0014 copy.jpg
 
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jring

Well-known member
Hi,

thanks Bill for sharing, so for explanation, step means the difference in height between the two images - this is the smallest tolerance. Divergence means the two tubes are pointing horizontally apart - the tolerance is double that of step and convergence is the tubes are pointing horizontally together - that is the highest allowable tolerance of four times that of step. All values in arcminutes (1/60 of a degree)

And you need to get the two tubes inside of these tolerances not for one IPD setting but for all...

Joachim
 

WJC

Well-known member
Hi,

thanks Bill for sharing, so for explanation, step means the difference in height between the two images - this is the smallest tolerance. Divergence means the two tubes are pointing horizontally apart - the tolerance is double that of step and convergence is the tubes are pointing horizontally together - that is the highest allowable tolerance of four times that of step. All values in arcminutes (1/60 of a degree)

And you need to get the two tubes inside of these tolerances not for one IPD setting but for all...

Joachim
Hi Joachim,

In your country, Step is Dipvergence. Really, though, the "tubes" are almost irrelevant. Sometimes the "tubes" will be a little off from the axle but the optics will be correct. I know that gets into stacking BBs, but it is what it is.

Bill
 

tenex

reality-based
In 44 years of using various binoculars, I've never seen a perfect single circle as the combined FOV.
This is where my thoughts are going also. Are we talking about an instrument problem, or a misconception (perhaps from cinema?) of what binocular views look like? Let's concentrate on the images of objects instead of the overall shape of the view. If objects come to a nice sharp focus and viewing them doesn't quickly become tiring, the bino may be performing as it should.
 

WJC

Well-known member
This is where my thoughts are going also. Are we talking about an instrument problem, or a misconception (perhaps from cinema?) of what binocular views look like? Let's concentrate on the images of objects instead of the overall shape of the view. If objects come to a nice sharp focus and viewing them doesn't quickly become tiring, the bino may be performing as it should.
As Aristotle was known to say, "BINGO."
 

dannat

Well-known member
Apologies if this a is a totally stupid question.

I have a pair of Viking Badger binoculars that I've had for a short time as my first pair of Binoculars. I can get a clear image in the centre when looking through but I can't get both barrels to make a one circle (does that make any sense?)

I don't think its a collimation issue as the centred image is in perfect focus but I see double rings on the outside of the image. I called Viking and they said it may be an issue with the focusing rods. I don't really want to send them back if its me being a total wally and I haven't adjusted something correctly. Any ideas?

I'm not sure if this could be a vision issue. I have a strong left eye dominance, don't know if this may have a bearing.
i may be totally misreading you but do you have the 2 barrels set apart at the right s=distance for the width between your eyes, called the ipd, have you adjusted the the distance the 2 barrels are apart, ie swung them further in.out whilst looking thru them?
 

Bluben79

Member
United Kingdom
This is where my thoughts are going also. Are we talking about an instrument problem, or a misconception (perhaps from cinema?) of what binocular views look like? Let's concentrate on the images of objects instead of the overall shape of the view. If objects come to a nice sharp focus and viewing them doesn't quickly become tiring, the bino may be performing as it should.

Thanks for all of the replies and thanks thanks Tenex, I feel that you're response has resonated the most.

I've been out everyday for a week now and I think I've measured my expectation of what I should see. The centre of the image is bright and clear and I suppose that's what is important.

I'm looking to buy a new model though as my interest in birding is growing exponentially on daily walks with new species being discovered.

Thanks to all on this forum for your help and advice. It's great to have some pointers from more experienced folks.
 
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia

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