Received: 1962 Trinovid 10x40 – first impressions (1 Viewer)

[tenex]

so there are gems out there

If these early silver coatings were so prone to oxidation, how have the gems survived? In what conditions must they have been kept -- low humidity, for example? -- and how much longer can they be expected to last?

 

[Tristram]

I may have given you some false hope. I agree with everyone else that this is likely a lost cause, but since you're going to have the binocular for a couple of days you might want to try some diagnosing yourself. I would suggest shining a flashlight into the binocular from both ends while looking into it from the opposite end. Move the flashlight and your eye around. You may be able to tell whether a prism glass surface in the middle of the binocular or a lens surface in the eyepiece near the rear is the location of the discoloration.

Another possibility is that rain water penetrated the unsealed eyepiece and left a stain behind when it dried out

Thank you, that is what I shall do then. Since I got a good price to begin with (I talked the seller down significantly from the asking price), I would be willing to spend a couple hundred dollars if I were reasonably certain of getting the problem fixed. Otherwise, back it goes. It would be cool to have one of these from the very first year they were made, wouldn’t it?

 

[Binastro]

I have a Trinovid 10x40 122m 798xxx.

It has rubber eyecups.

I bought it from a firm that I reliably bought from for years, but his claims for this binocular were just not true.

It is faulty.

I will have to test again to see the faults.

I never send stuff back. Too much hassle.

But I never bought anything again from this shop, that I had visited many times before.

I did buy a hand held spectroscope from him for £10 as he had no idea what it was, it was boxed with extras.

So, I think I am even.

In the case of the Trinovid in this thread, there is a choice, but little time.

Regards,
B.

 

[mwhogue]

If these early silver coatings were so prone to oxidation, how have the gems survived? In what conditions must they have been kept -- low humidity, for example? -- and how much longer can they be expected to last?

tenex,

To begin by quoting one of my favorite antediluvian movie lines "Every human endeavor involves a particle of risk Jack".

My WAG regarding preservation would include limiting use to mostly low humidity environments and storage in reasonably consistent (including low humidity), as opposed to varying conditions. The OP's experience appears to be similar to one recounted by @eitanaltman @ 18 months ago with a Leitz 6x24 - one barrel significantly compromised and the other perfectly fine, so there are obviously no silver bullets.

To be clear, I am not recommending that anyone buy significantly older bins with silver coated prisms. Rather, that there are old specimens out there which have somehow survived in good condition.

As to how much longer we can expect any of these old gems to last, maybe someone else knows?

Mike

 

[Alaska4me]

[I seem to have done that wrong. Can someone tell me how to flag an individual here?]

To flag, simple type @username, as in @Tristram. That's all.

 

[MiddleRiver]

I had a 7x35B from 70’s that had the prism coating oxidation issue. The impact was simply that they were hazy and IQ was somewhat poor. Two years ago I sent them to Leica NJ and they explained that it could no longer be repaired. They offered me a very nice deal on new trinovids which I gladly took advantage of.

At that time I also talked to repair shop and they said they could refurbish the binos but did not recommend it due to cost and uncertain outcome etc.

Buy Retrovids and never have to look back ;-)

 

[John A Roberts]

Alternatively (?) . . .

Frank (aka LPT here on BirdForum) has described a DIY method that he used, to successfully replace a deteriorated silver coating on a Trinovid prism:

https://flic.kr/p/dzyyL9

Click on the image to be taken to the Flickr page including the text.


John

 

[henry link]

Another great find from the depths of internet, John! Also, my hat's off to Frank for coming up with such an ingenious fix.

I see that Edmund still sells these mirrors, so Tristram, if bad mirror coating is the problem there is a solution, provided you can find a technician willing to take on a very unusual repair for a price you're willing to pay.

 

[Alaska4me]

It would be cool to have one of these from the very first year they were made, wouldn’t it?

Yes it would.

1962 was an exceptionally good year

 

[Owlbarred]

Otherwise, back it goes. It would be cool to have one of these from the very first year they were made, wouldn’t it?

Absolutely incredibly cool to have them, for sure, but perhaps as a collector's keepsake rather than a functioning binocular. The 'good' prism may well suffer the same fate as the tarnished one. A bit like owning a wonderful old Porsche -- just when you think it's fixed.... Repairing a prism, even using the ignenious method described by LPT seemingly is not for the faint of heart, e.g., collimation of the 'reburbished' Uppendahl prism

 

[Binastro]

The 1974 Trinovid 10x40 122m was tested again.

The most annoying feature is 4 or 5 bits of debris in the eyepieces.
Two are out of focus but disturbing against the sky.
One is very sharp and a black sliver near the field edge and another two very small bits.

With a fussy background, say in the street none of the debris is seen.
It probably needs disassembly of the eyepieces to clean the eyepieces.

The prism on one side has blotchy marks non central.
The other barrel prism has a fainter overall stain.

Looking through the binocular the stains don't cause much of a problem except some loss of contrast.

There is also veiling glare, probably partly due to the stain.

At night ghosting is minimal

Star images are good and tight.

Alignment is good.

The field is large.

The coatings are good for the age.

The hinge is too loose, but the binocular can be used without much trouble.

Centrally there seems to be no CA, but this creeps in off axis.

The resolution is good, but I can't hold it as steady as some other 10x binoculars.
Maybe the small size and light weight are the reason.

The seller described the binocular as very good with no problems.
That is why I stopped buying from him.

Using the binocular is not relaxing.

The 8x32 BA is very relaxing.

So this 10x40 Trinovid looks nice but is not a binocular I would use, or bother to try and get repaired.

Regards,
B.

 

[Trinovid]

Frank (aka LPT here on BirdForum) has described a DIY method that he used, to successfully replace a deteriorated silver coating on a Trinovid prism...

Great find John, and here’s the accompanying text that LPT posted.

Post by LPT (Frank)​

This well-used binocular when received needed an unusual repair. The seller accurately described the right side view as poor, and I hoped all it required was a routine cleaning of the internals (which is usually the case barring badly chipped or fungus damaged prisms).
However, upon disassembly the internal optics were found to be in good condition except for the silvered prism face which was badly deteriorated i.e. the silvered prism slope was bubbled and peeling off causing an awful brown and splotchy view. I easily removed the remaining silvering with acetone but that made the view even worse. It became incredibly dark with maybe 20% light transmission. With nothing to lose, I purchased a 3”X3” 1 mm thick square of aluminized glass from Edmund Optics, cut it to the shape of the prism slope in need of mirroring and using Norland Optical Adhesive 61 glued it onto the prism slope, its aluminized side directly against the prism surface. And ... it worked.
Afterward, I couldn't tell the difference between the view on the left side (with optics in good condition) and the one the right with the re-mirrored prism. I'd expected that even if the experiment had been successful the right side view would have a bluish tone due the aluminum coating but this did not occur. Both sides had the same warm color tones. After this picture was taken, the top of the mirrored glass was painted black (although I'm not sure this was necessary to improve image reflection).

 

[NDhunter]

Frank is a great resource with a large collection and much experience. He lives just north of me
in Manitoba. Maybe someone can post a link to his collection, I don't have it.
It is a small world.
Jerry