October 2010, Nikon Kenkyukai Tokyo, Meeting Report

October 2010, Nikon Kenkyukai Tokyo, Meeting Report

Old Vintage NIKKO Big Binoculars Show

October 16, 2010

Nikon Kenkyukai

Tokyo Meeting

Old Vintage NIKKO

Big Binoculars Show

October Wind

The Nikon Kenkyukai Tokyo Meeting in October was held in Harumi near Tokyo bay, and we researched the historical old vintage NIKKO big binoculars.

October Wind in Harumi, Tokyo

Let's join the Tokyo Meeting with us.
You can touch the super collection by your internet PC.
Nippon Kogaku collimator, surveying instruments, elbow telescope, type 92 telescope, 20x120 monocular, heavy machine gun scopes, field gun scope, 5cm telescope, very old 3 inch telescope, aviation binoculars, big binoculars and high view angle big binoculars with you.
They are old but great collection.

Nippon Kogaku Collimator

Nippon Kogaku Surveying Instruments, Level Type E, Showa 34 (1959)

Nippon Kogaku Elbow Telescope

Nippon Kogaku 15x50 Binoculars

Nippon Kogaku 6.5cm Telescope

Historical Binoculars, Telescopes and Big Lenses

Nippon Kogaku Type 92 Telescope

Nippon Kogaku 20x120 Monocular

L: Heavy Machine Gun Scopes, R: Field Gun Scope

Nippon Kogaku Military Instrument that Measures Flow of Wind

L: 5cm Telescope, R: Very Old 3 inch Telescope

Nippon Kogaku 5cm Telescope Showa 25 (1950)

Very Old Vintage Telescope for School Boys and Girls

Nikko Aviation Binoculars Type-I for the Imperial Japanese Army Air Force

Special Study of the Historical Old Vintage NIKKO Big Binoculars

You can see and touch Shigeki Terada and Neko-san's big binoculars collections.
They are old star but their eyes are very sharply clear.
Binoculars of Nippon Kogaku, made in Japan have eyes like a hawk.

Nippon Kogaku Big Binoculars for Fishery

Original Maintenance Brush and Filters

Old High View Angle Big Binoculars

Nippon Kogaku Brass Plate

Nippon Kogaku 12cm Big Binoculars

Eyepieces of the Big Binoculars for Battleship

Adjustment Mechanisms of Width of Eyes

Big Binoculars with Angle Scale Board

Very Vintage Small Binoculars

Please see beautiful very vintage small binoculars on the collection table.
Do you know very old Fujii brother's binoculars?

Even if all 70 years or more pass, fine quality leather cases are beautiful

The World of Wonderful, Small Binoculars

As you know Meiji Restoration was in 1867 and the Fujii Lens Seizo-sho (Fujii lens factory) was established by two engineers to make the optical instruments domestically in 1909.
Two Japanese engineers were Fujii Ryuzo and Fujii Kozo brothers.
You can see and touch the super vintage VICTOR 8x20 by Fujii brothers.
This VICTOR 8x20 binoculars were manufactured 100 years ago!! (Perhaps, in around 1911)

VICTOR, the First Prism Binoculars in Japan, 100 Years Ago

Fujii Lens Seizo-sho, 20x8 Binoculars

Very Fine Product, VICTOR 20x8 Binoculars

Very Rare Nippon Kogaku Wide Field Binoculars,
The Imperial Japanese Navy Aviation Technology Laboratory

Mark of the NIKKO, Nippon Kogaku Kogyo

Mark of the Imperial Japanese Navy Aviation Technology Laboratory

Super Otaku Presentation for Nippon Kogaku Enthusiast

Shigeki Terada, an engineering specialist of the Dodaira astronomical observatory, a member of the Nikon Kenkyukai Tokyo, director of the telescope division talked about his great work.
Let's enjoy a presentation program in Tokyo Meeting mini convention together.
Please don't sleep!

Tokyo Meeting Mini Convention

Shigeki Terada's Excellent Presentation

The following is summary of Shigeki Terada's presentation.

A Historical and Optical Study of Big Binocular Telescope in the Showa Era

Recently, I got a chance to restore pre-WWII high-view angle binocular telescope and 30's of Showa-era binocular telescope.
This abstract state some informations from this two binocular telescopes during the restoration.

   Sample 1 Nikko 15x4 10cm

Sample 1 is Nikko 15x4 10cm high-view angle binocular telescope. Serial number is 274.
Production period was confirmed that there is a sign "Showa 12th November" on the Rhomboid prisms. This sample is come from Kawasaki city Kanagawa prefecture in Japan.
Objective lens effective diameter is 10.5cm, focal length is 525mm.
Lens type is 2 elements Fraunhofer type achromat spaced by 30micron thickness tin foil.
Radius of each lens measured by spherometer, and focal length measured by nodal slide substituted to optical designing software.
The result suggest L1 (1st convex lens) is made of BK8, L2 (2nd concave) is made of F1.

The eyepiece f=35mm, FOV=70degree, consist of 3 groups 5 elements.
This design is very similar to the Japan patent No.87139 invented by Kakuya Sunayama in Showa 5th. But 1st (nearest to OBJ.) and 3rd radius are plane.
This modification may be a "Kaizen" to improve productivity.
Only L1 is made of BK7 was known.
Electing and eye distance adjusting system is made by 70degree Amici roof prism and Rhomboid prism. Any anti-reflection coating aren't applied.
Waterproof mechanism is made with applied grease and waterproof oil cray on every spacing (gap) of screws and labyrinth structure on the mating surfaces of every franges.
These are still keeping effectiveness, every optical surfaces inside the tube was very clean and no stain.

Some writings suggest te tube (main mechanical structure) is made of "Electron" (magnesium alloy), but this sample looks made of usual aluminum alloy.
Eye distance adjusting mechanism is made by very unique, interesting letter form of "8" shaped steel belt around between 2 prism barrels.
But the steel belt was turned off long time before, may be during in the battle field.
Newly reproduced one is replaced.
Painting color is yellowish gray, and cell of lenses have usual flat surface.
But tube and prism barrel have sand touch surface made by sprinkling cork powder.
After cleaning of all optics, very clear image is restored.
Although stray lights made by non-anti-reflection coated surfaces are strongly observed, every aberrations are well corrected even if consider F5 objective. Contrast of images are very high.

   Sample 2 Nippon kogaku 20x3 12cm

Sample 2 is Nippon kogaku 20x3 12cm binocular telescope. Serial number is 7230.
Production period could not be confirmed that there is no obvious sign, but it is estimated Showa 37th from serial number.
This sample is come from Yaizu Shizuoka Prefecture in Japan. Yaizu is famous for the fishery. May be used by tuna or bonito fishing vessel.
Objective lens effective diameter is 12cm, focal length is 600mm.
Lens type is 2 elements Fraunhofer type achromat spaced 2.5mm using brass spacer ring.
With same measuring method, estimated glass type are BK8 and F1.
The eyepiece is also similar design to sample 1. f=30mm, FOV=70degree, consist of 3 groups 5 elements.
Electing and eye distance adjusting system are made by PorroII prisms which optical axis shift distance is 52mm.
Single layer MgF2 anti-reflection coating are applied on all transmitting optical surfaces.

Waterproof mechanism is similar to a sample1. O-ring are applied nowhere.
Airtighting are still keeping effectiveness, every optical surfaces inside the tube was very clean and no stain.
There is a dryer (silica-gel) case between two main tubes. Two black silk silica-gel bags (weight:2x50g) are in it.
After restoring moist dryer and refilled, moist indicator (CoCl2 instilled paper) put on the inside of the right hand tube indicate good humidity condition more than 1 month.
Comparing with sample 1, most mechanical parts made of bronze or brass are replaced to aluminum alloy assumed for the purpose of weight reduction.
Painting are dark reddish gray flat surface on hoods and eyepiece barrels.
but the tube and prism barrels have dark greenish gray crepe touch surface.
After cleaning of all optics, very clear image is restored.
Stray lights are also made minimum by anti-reflection coated surfaces.
Although slite chromatic aberration are observed, every aberrations are well corrected.
Contrast of images are very high.

In conclusion, compared with a state of the art wide field binoculars using ED/SD glass and multi or phase compensating coating, inferiority of transparency and remaining chromatic aberration are obvious and "outdatedness" are felt.
But disparity between new one and them is not so big contrary to the anxiety.
By the point of view for the pre O-ring water-proof/anti-humidity technology and durability for optical weapon are already come up to completeness and are laudable.
In particular, the technical level of this high-view angle binocular telescope only passed 20 years from establishing of 1st designing are laudable.
The assumed designer Kohgoro Yamada, the then Naval Technical Rear Admiral and Kakuya Sunayama, the then Senior Manager of Designing Division of Nippon Kogaku should be looked up to as a great engineer.

Shigeki Terada
An engineering specialist of the Dodaira Astronomical Observatory
A member of the Nikon Kenkyukai Tokyo, Director of the Telescope Division

Special Download
A Historical and Optical Study of Big Binocular Telescope in the Showa Era
Japanese(PDF)
Do you know the black silk bag is stored in binoculars?
This Japanese PDF file was made for Nippon Kogaku enthusiast.

Special Study of Early Old Telephoto Nikkor Lenses

Akihiko Suzuki, a Nikon F specialist explained study results concerning the early old telephoto Nikkor lenses.
Please see Nikkor 400mm F4.5, 600mm F5.6, 800mm F8, 1200mm F11 and Reflex Nikkor 1000mm F6.3 put on the collection table.
All lenses are the early models. The front and rear caps made of leather are wonderful.
You can see and touch a lens support tool for Nikkor telephoto lenses.

All of Older Telephoto Nikkor Lenses and Focusing Unit

1200mm F11, 800mm F8, 600mm F5.6 and 400mm F4.5 Lenses

Auoto Nikkor Telephoto Zoom 200-600mm F9.5-10.5

Nikkor Telephoto Lenses and Wonderful Leather Caps

A Lens Support Tool for Nikkor Telephoto Lenses

F Mount Reflex Nikkor 1000mm F6.3

Very Rare Distance Scale Plate for Focusing Unit of Telephoto Lenses

Happy Binoculars Party

We went out, and verified the performance of big binoculars actually.
The binoculars watched the sky in the Haneda airport.
Do you have the experience of watching the far world with old vintage NIKKO big binoculars?

Super Meeting with Old Vintage NIKKO Big Binoculars

Very Beautiful Scenery

Very Heavy Old Binoculars

Periscope Binoculars (We call crab's eyes)

Very Old Nippon Kogaku 3 inch Telescope

Very Wide Field Binoculars 10x70 (70 degrees!)

Setting of Old Vintage Big Binoculars

Excellent! Fantastic! Gorgeous!

Unbelievable! Old Nikko Great!

Big Eyepiece of Old Vintage 20x120 Monocular

Fujita and the 20x120 Monocular

Children who study science from Kenkyukai member

Katsuharu Takashima is observing the missile that comes flying

Nice Iced Coffee

A Happy Tallking with Coffee and Big Vintage Binoculars

Enjoying Big Vintage Binoculars

Big Lenses as Beautiful as Crystal

Big Lenses as Beautiful as Samurai

Big Lenses as Beautiful as Goddess

Fantastic Happy Meeting

It was a wonderful meeting.
We understood that old binoculars have the superior performance if you maintain them with love.
We respect the designer and the craftsman who has the excellent technology and zeal though 70 years or more passed.
Even if no one praises you, we praise you.
Thank you Kohgoro Yamada, the then naval technical rear admiral and Kakuya Sunayama, the then senior manager of designing division of Nippon Kogaku.
Good job Nippon Kogaku! Thank you MADE IN JAPAN!
It was a fantastic and happy meeting.

Nikon Kenkyukai Tokyo Super Meeting

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Copyright Michio Akiyama, Tokyo Japan 2010, 2016