20x120 Toko Big Eye binoculars

[Callred1975]

I just purchased a great looking pair of Vintage WW2 era Toko Big Eye binoculars. I would love to learn all I can about these. They are in fantastic original, non-restored condition and have great optics.  

I’m interested in hearing what everyone thinks they’re worth. I want to know if I overpaid, underpaid, etc.

In the end, I really don’t care because I already bought them and no way am I returning them.

I’m not gonna say how much I paid and I won’t get my feelings hurt no matter what estimate anyone makes. I’m happy with my purchase and that’s all that matters to me.
 

Thanks!

 

[Callred1975]

If anyone knows the English translation of the writing on the brass plate, please let me know.

[Callred1975]

If anyone knows the English translation of the writing on the brass plate, please let me know.

Just found out some more info on my particular Toko Big Eye’s...

*22.5 degree inclined eyepieces 
*Erfle eyepieces 
*60 degree FOV
*Large, Porro 2 prisms w/exit face angled at 22.5 degrees
*Swiveling Rhomboid Prisms to adjust IPD
*Performance rating= EXCELLENT 

This information was acquired from:

 

http://home.europa.com/~telscope/japanbin.txt

[Ciaran Meier]

Wow, they do look the part ! Can't wait to read your first light report 😀.

Clear Skies. 

Ciaran. 

[geoflewis]

Me too....

[Stormbringer]

And me 🍻

[Callred1975]

I’m debating on whether or not to do any type of cosmetic restoration on them due to their extreme rarity and excellent original condition.  I actually contacted the National Science Museum in Tokyo to see if they would be interested in acquiring them before I make any changes to them. As much as I would hate giving them up (I’ve dreamed of owning a pair of Big Eyes for years),  I will give them up as long as I’m able to replace them with a similar (and less rare/historically significant) pair of binos.

 I’m an idiot right?

[Callred1975]

That’s great Kev!

LMAO

[Ships and Stars]

There's a binocular book written called something like 'binocular facts and fallacies'. The author was a US Navy optician on binoculars and then repaired binoculars for twenty odd years. Sorry I can't give a name at the moment, but imagine he'd know a lot about these, or someone who would. As far as restoration goes, I wouldn't touch anything that can't be reversed. Awesome binoculars by the way!!

[Ships and Stars]

Here we are: William Cook, author.

https://books.google.com/books/about/BINOCULARS_Fallacy_and_Fact.html?id=CHexswEACAAJ

[Callred1975]

I’m currently researching the bino’s provenance as well.

[Ships and Stars]

Here's the book on AbeBooks in case you haven't found it elsewhere and wanted it, the seller is in Maryland. Let us know what you find out. 

https://www.abebooks.co.uk/servlet/BookDetailsPL?bi=30323045778&searchurl=n%3D200000237%26bi%3D0%26ds%3D30%26bx%3Doff%26sortby%3D17%26tn%3DBINOCULARS%3A%2BFallacy%2Band%2BFact%26recentlyadded%3Dall&cm_sp=snippet-_-srp1-_-title1

[Peter Drew]

I would leave them as they are.  They would most likely appeal to a collector and could well realise a price that would cover the cost of a modern binocular of similar size with the advantage of better lenses, coatings, ability to change eyepieces, angled viewing and replacement components in a case of damage.  Would love a look through though!.     😀

[Callred1975]

That’s the same thing I was thinking Peter.   

[Callred1975]

[Callred1975]

[Callred1975]

[Callred1975]

[Callred1975]

[michael.h.f.wilkinson]

Amazing piece of kit. I think selling them to a collector and buying a new pair is indeed the best option, newer bins will have better transmission, better colour correction, and the option of inserting better EPs than the Erfle type used here. The photos suggest the optics are either uncoated or simply coated with MgF2. As I recall the latter reduces reflections from 5% to 1%. Modern coatings reduce that to 0.2%. Given a conservative estimate of the number of glas-air interfaces, MgF2 coatings would lead to a light loss of around 15%, compared to 3.2% for full multicoating. Improvements in transmission through the optical glass should be of a similar magnitude. 

[Callred1975]

If I were able to somehow locate a different set of Toko eyepieces from another pair of Big Eyes of that era, does anyone think it possible to swap the eyepieces for a different magnification?

(obviously they would have to be the same size/shape)

 I’m probably never gonna even attempt doing this.  I’m just curious if anyone thinks it’s possible.

[Callred1975]

I’ve gotten an English translation of the brass plate and round brass cover...

It reads：

 

Modified 12cm high angle binoculars

MARINE Weight 23.300kg

               NO. 158

               SHOWA 19th April

Made by TOKO 

On the desiccant cover, it reads:

Open-Close

Desiccant

Cover

[Callred1975]

Correction:

After getting the brass plate translated, I have discovered the true production year is 1944 not 1940.

[Stormbringer]

1 hour ago, Callred1975 said:

Correction:

After getting the brass plate translated, I have discovered the true production year is 1944 not 1940.

Still WW2 era tho 🍻

Wonder if they ever served in a ship ?

[Callred1975]

I’m in the process of establishing provenance.  I should be able to trace it’s origin (hopefully).