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Leica Trinovid BN diopter problem (1 Viewer)

apg

Member
Canada
Hi all - new to the forum here,

I recently purchased a pair of new-old-stock Leica Trinovid BN 10x32s which look to be in great working order except for the diopter dial, which shows the incorrect setting on the disc.

I normally use a 0 setting, but in this case, when the dial is set to 0, there’s a significant focus difference from one barrel to the other. It’s the same whether I’m wearing glasses or not and only when the diopter is set to approx +8 (see photo) are both barrels in focus. I’ve confirmed this by looking through each barrel with the same eye and the difference is night and day.

My question is… what could be the cause of this misalignment? Is it likely the dial or barrel which is out of alignment? Does it even matter? It doesn’t seem to affect the view in any way but I’m concerned I could be missing something.

I’d rather not send them in for repair If it’s purely superficial, but if it’s a sign of an underlying problem I would consider it.

If anyone has any thoughts, I’d really appreciate hearing them - Thanks,

Alex
 

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If you don't have issues with close focus, and if you can focus on a star and then push the focusing beyond that, you should be okay.
 
If you don't have issues with close focus, and if you can focus on a star and then push the focusing beyond that, you should be okay.
Thanks for your reply Foss, I checked both and close focus is good (as stated at 2.1m) but infinity seems ever so slightly soft but that could be due to my eyesight. Doesn’t seem to be any overdrive but I believe that’s a known issue with this model.

I appreciate your input, thanks.
 
Thanks for your reply Foss, I checked both and close focus is good (as stated at 2.1m) but infinity seems ever so slightly soft but that could be due to my eyesight. Doesn’t seem to be any overdrive but I believe that’s a known issue with this model.

I appreciate your input, thanks.
Had the same problem with my 10x32BN, sounds like the diopter adjustment has slipped. Sent mine off to Leica & they returned them after a full service and new armour free of charge. The diopter adjustment is now fixed and correct for my eyesight.
 
I’d say that’s what has happened. I’m guessing mine aren’t covered under warranty since I purchased them second-hand, but it’s good to know they can be easily fixed with a service at least.

Thanks for your input Minerva24
 
I’d say that’s what has happened. I’m guessing mine aren’t covered under warranty since I purchased them second-hand, but it’s good to know they can be easily fixed with a service at least.

Thanks for your input Minerva24
I'm sure Minerva24 is correct. This seems to be a relatively common issue. I purchased some 10x50 BN's a couple of years ago which had the diopter dial showing that it was out by two diopters. A phone call to a well known ex Leica technician here in the UK confirmed diopter slip to be the most likely cause and a simple reset and tightening of a screw would fix it, a quick and simple job (apparently).
 
I’d say that’s what has happened. I’m guessing mine aren’t covered under warranty since I purchased them second-hand, but it’s good to know they can be easily fixed with a service at least.

Thanks for your input Minerva24
They will be under the 30 year Leica warranty.
My 'as new' BN's had no problems, but I asked Leica to give them the once over, mainly as they had been sat for 18years.
I was also concerned about the waterproofing and nitrogen filling.
All done free of charge by Leica. Superb service.
Strangely, mine still have 12years warranty remaining, whereas a brand new Trinovid HD only has 10..... result(y)
 
The only thing a bit odd here is that a "NOS" BN would have so badly miscalibrated a diopter out of the box. I would send this in myself... in fact I did this spring, and our BN came back not just recalibrated but sharper than ever. (Leica US, in NJ -- not sure who's involved in Canada?)
 
The only thing a bit odd here is that a "NOS" BN would have so badly miscalibrated a diopter out of the box. I would send this in myself... in fact I did this spring, and our BN came back not just recalibrated but sharper than ever. (Leica US, in NJ -- not sure who's involved in Canada?)
I suspect the diopter issue may be the reason they survived new-in-box for so long without a buyer. Maybe they were returned and/or the dealer put them to the side. They’re mint otherwise and still smell new even.

I think I will send them in just to be sure, but I already love them so much they’re hard to part with even temporarily.

Thanks to everyone who contributed knowledge and input.
 
I’d say that’s what has happened. I’m guessing mine aren’t covered under warranty since I purchased them second-hand, but it’s good to know they can be easily fixed with a service at least.

Thanks for your input Minerva24
Warranty is not owner dependent, but rather time limited. You can be the 50'th owner and if in warranty window, they'll take care of it. I strongly recommend you simply give them a call, provide s/n, describe issue... and let us know how it went ;-)
 
I think I will send them in just to be sure, but I already love them so much they’re hard to part with even temporarily.
I used this model for ~15yrs, just carried it again for a few days on a trip, and still love it. Enjoy yours! As I recall service took about 6 weeks this spring.
 
Warranty is not owner dependent, but rather time limited. You can be the 50'th owner and if in warranty window, they'll take care of it. I strongly recommend you simply give them a call, provide s/n, describe issue... and let us know how it went ;-)
Thanks MiddleRiver, I contacted Leica USA and a customer care advisor told me a bill of sale would be required to determine how much warranty remains - which makes sense given the 30-year warranty period begins on the date of sale by an authorized dealer (stated on the warranty card enclosed within the box). Unfortunately for me, my warranty card bears neither a date nor a signature from an authorized dealer and so perhaps escaped the factory/dealer onto the gray market without an official bill of sale.

Somewhat curiously, the box nevertheless includes a Test Certificate signed in pen and assuring quality control, so the diopter miscalibration either eluded the examiner or arose later. There are no signs of use, so I have to imagine it slipped from being dropped if the latter was the case.

Is anyone familiar with how the diopter graph and setting interact in the Trinovid BNs? I'd love to find out how such an issue arises in the first place, if not during assembly.
 
I’d recommend pushing back a little. I’ve had two vintage binos taken care of and in neither case (one was actually bought in Portugal by my dad then inherited by me) was I expected to show proof of purchase. That said, they were both from legit dealer, so I believe Leica could find records.
If that’s not the case, I’d better get cracking - all my current bins are legit but I’ve sure as heck never registered them or saved receipts!
 
I obtained a NOS 10x32 BN myself a few weeks ago and have no issues with the diopter but I’m almost sure that (here in Europa at Leica Portugal) they will service it free of charge if the warranty is not over 30 years.
 
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I obtained a NOS 10x32 BN myself a few weeks ago and have no issues with the diopter but I’m almost sure that (here in Europa at Leica Portugal) they will service it free of charge if the warranty is not over 30 years.
Thotmosis, did your recent purchase include a warranty card inside the box? If it is marked at the back with a date and signature of sale, that will tell you exactly how much warranty period remains (beginning from the date of sale).

In any case, the BN model group as a whole is not more than 30 years old regardless of date of sale (statement valid until 2031), and so I think I will take MiddleRiver's advice and push back a little.
 
Thotmosis, did your recent purchase include a warranty card inside the box? If it is marked at the back with a date and signature of sale, that will tell you exactly how much warranty period remains (beginning from the date of sale).

In any case, the BN model group as a whole is not more than 30 years old regardless of date of sale (statement valid until 2031), and so I think I will take MiddleRiver's advice and push back a little.
No not a date and signature of sale. But no worries, Leica will take care of us.
 
Hi,

for most people the described problem is purely cosmetic... unless your prescription is quite different in sphere between the eyes, in which case you might not have enough diopter travel to get both tubes to focus.

If they're still under warranty (currently transferable 10 year from date of sale with the need to provide a sales receipt or filled in warranty card - both from an authorized dealer), you might send them on a trip to Portugal for a once-over...

Joachim, who would probably just use them...
 
No not a date and signature of sale. But no worries, Leica will take care of us.
For what it's worth, I got an update from Leica USA's customer care advisor saying "I’m sorry, unfortunately, the bill of sale is how we would determine the warranty." and so I've decided not to send my BNs in for a purely cosmetic issue at my own cost.

It may be a different story abroad, but I would certainly encourage anyone in North America without a bill-of-sale to find out for themselves whether their warranty will be honoured or not. Buyers of NOS beware.
 
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Where is the problem here? If you've just purchased a new-old-stock BN complete with a warranty card, just get a purchase receipt from the dealer and send these in to Leica! Then get your service. A discrepancy so large that you're barely able to use it (as someone else might not) should be fixed.
 
Where is the problem here? If you've just purchased a new-old-stock BN complete with a warranty card, just get a purchase receipt from the dealer and send these in to Leica! Then get your service. A discrepancy so large that you're barely able to use it (as someone else might not) should be fixed.
There is no problem anymore as far as I’m concerned. Initially I thought the slipped diopter might be a sign of something serious, but that seems not to be the case.

Mine were NOS purchased second-hand in an auction, not through an authorised dealer. From whom the previous owner bought them or how they arrived on the market, I have no idea because there’s no paper trail.

I just wanted to clarify for anyone in the same boat, warranties in North America require a bill-of-sale from an authorised dealer.
 

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