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Does anyone mark their diopter setting (1 Viewer)

bobmcc81

New member
Hello,
I have learned about the diopter setting on my binoculars. Setting it correctly has made a world of difference in how fast I can get on focus with a both eyes view. I thought I just had cheap binoculars :) ..

Does anyone use like a little dab of white out or nail polish to mark the diopter setting for quick reference, it seems like it could get changed by mistake pretty easily. I don't think the setting ever changes for my eyes unless my eyes change.

Thanks
 

John A Roberts

Well-known member
Australia
I agree with both Jerry and Mike!

With push or pull, click set diopter adjustments, I’ve never had a problem with a mechanism unintentionally moving

And most friction set adjustments are also usually fine e.g. the ones often found on the oculars of older style Porro prisms

However, I have had the settings on some Porros ‘wander’ due to insufficient tension. But a rubber band or two wrapped around the fixed eyepiece body,
and bearing on the adjustable eyepiece, provides sufficient drag to solve the problem


John
 

CMB

Well-known member
Good to hear that you learned about setting the diopter! Makes a world of difference.

As everyone has shared, once properly set you shouldn’t have to reset it. But...

I had one set of bins with optics that were a bit goofed where a dab (or two or three) of something to mark diopter positions would have been helpful. But this experience is not how it should work.

These are older ~$400 roof style bins with a locking diopter. When I first bought them I used them mostly in wooded areas where the viewing was mostly at shorter distances, and I didn’t notice anything was off. A few years later I started using them in more open areas and I found my regular diopter setting didn’t work. When viewing objects at long distances I had to change the diopter for best focus at that distance, and adjust it again when viewing at shorter distances. With these bins eventually I found a setting where everything was equally fuzzy in the right eye at all distances.

Yes, I have different bins now.
 

Foss

Well-known member
I'm tempted on the Foton 7x35s I keep in my car...susceptible to change with the diopter so close to the focuser. But nah.
(If I did, I might experiment with white out on a pair of junkers first to see if it comes off without lifting the paint).
 

Pinewood

New York correspondent
United States
... But a rubber band or two wrapped around the fixed eyepiece body,
and bearing on the adjustable eyepiece, provides sufficient drag to solve the problem


John

Hello John,

I had to do the same with a Swift 8.5x44 Audubon. I had to do the same with a Foton 7x35, as did Foss.

Stay safe,
Arthur :hi:
 

peter.jones

Registered User
Supporter
It's the main criticism of the Zeiss pocket for many. The diopter can move quite easily. I tried a little dab of ink, but know where it should sit now, just a touch off centre.
 

Stephen Prower

Well-known member
I recycle from another thread in case it might help anybody a photo of the field modifications that I have made to an Opticron 8x32 SR.GA with a freelly moving diopter adjuster.

I bought the Opticron in 2010. The diopter adjuster moved freely from new. I asked Opticron to tighten it up, but they did not recognise it to be in a faulty state.

So I lived with the adjuster.

Eventually, having successfully relubricated the adjuster of another porro, I set about doing the same with the Opticron.

However I could not get into the ocular to do the job. One of the set screws that I needed to undo was stuck solid in place. I tried freezing the adjuster in place with a 'rubber band' cut from bicycle inner tube, but couldn't achieve a mechanically sound fix.

By now I was using the thumbs up grip. It meant that I was always nudging the adjuster with my thumb, thereby knocking it out of position.

So I bodged.

1) I stuck down a piece of sticky-backed velcro as a 'reminder' where I should place my thumb out of the way of the adjuster

2) I marked the correct position of the adjuster with sticky-backed white paper overlaid by clear sellotape. I used dimensions for the white paper marks that meant that I could check at a glance without need to peer closely that the adjuster was set correctly.

The bodges have worked.

I reflexly check the white markers when I pick up the binocular. My thumb settles reflexly upon the velcro.


Stephen
 

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lmans66

Out Birding....
Supporter
United States
No, once you set it you should be good to go. No reason to mark up the binoculars.

Jerry

I tend to disagree ....just a bit. I have found times in the morning when my eyes are tired, or ....the light is off or whatever, that I actually like to reset my diopter. Perhaps just me, but ....it works. I then will always reset back to it's previous spot later on.
 

peter.jones

Registered User
Supporter
Is it possible to "strengthen" the weaker eye to bring the dioptre back to central?!
I'm thinking using the weaker eye for telescope?
Maybe stop short of wearing a patch!
 

Roadbike

Well-known member
I can see marking the diopter setting if it helps setting the bin up. Anything to reduce the chances of missing a bird.
 

NDhunter

Experienced observer
United States
I tend to disagree ....just a bit. I have found times in the morning when my eyes are tired, or ....the light is off or whatever, that I actually like to reset my diopter. Perhaps just me, but ....it works. I then will always reset back to it's previous spot later on.

I agree with needing to adjusting the diopter, but not with marking up the binocular with paint or anything permanent.

Jerry
 

WJC

Well-known member
There is no need to do this as settings change with various viewing scenes.

The FOCUS always changes with distance to the target. However, if the observer sets the diopter adjustment when RELAXED (having learned to stare) that setting should remain the same throughout the observing session. The diopter setting is to compensate for the DIFFERENCE in the dioptric strength of your eyes and need not be fiddled with as that difference should remain the same whether your target is 50 feet or 5,000 yards away. :cat:

Bill
 

lmans66

Out Birding....
Supporter
United States
The FOCUS always changes with distance to the target. However, if the observer sets the diopter adjustment when RELAXED (having learned to stare) that setting should remain the same throughout the observing session. The diopter setting is to compensate for the DIFFERENCE in the dioptric strength of your eyes and need not be fiddled with as that difference should remain the same whether your target is 50 feet or 5,000 yards away. :cat:

Bill

Agreed.... and in one setting ...but I am speaking to getting up early...my eyes are tired, the light is dim etc....and my settings 'might' need adjusting as we move into the day. Not all the time, if much at all.....but I have noticed I prefer to adjust the diopter from time to time.
 

WJC

Well-known member
Agreed.... and in one setting ...but I am speaking to getting up early...my eyes are tired, the light is dim etc....and my settings 'might' need adjusting as we move into the day. Not all the time, if much at all.....but I have noticed I prefer to adjust the diopter from time to time.

You may find that your eyes are EQUALLY tired and that if you set the diopter adjustment properly to start with—at a relaxed setting—that you have no need to adjust. You are in Tucson with gives you a great opportunity to verify these comments through a fellow with a Ph.D. in both Precision AND Ophthalmic optics. :cat:

Just a thought,

Bill
 

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Jonno52

John (a bad birdwatcher)
Supporter
United Kingdom
I take a photo, as per the attached. Though with those bins, having a numbered scale, it's easy enough to just write down the setting.
 

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