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Asahi Pentax Marine Binoculars (1 Viewer)

clschmalz

Well-known member
I've recently had some questions regarding Asahi Pentax BIF Marine Binoculars. As a partial answer I'm posting the attached advertising sheet that accompanied the NOS pair I bought last year.

As I understand it the BIF models are descended from Asahi's Japanese military models. Mechanically they appear to be built like the proverbial tank. Optically they are as good as or better than Swaroviski or Nikon glasses I own.

Trust this information will be of interest to at least some on the forum.

Charlie
 

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Hello Charile, This is very interesting information.Thanks for posting this. I notice it lists fully coated optics on the nice picture of the 7x50BIF with the sailing boat in the background. I also noticed the prism housing looks the same in the 6x30 through 7x35 BIF and the weight is close 22.5 oz. through 24.4 oz. The 7x50 BIF prism housing looks a lot bigger as well as the wt. 45.8 oz.
Regards,Steve
 
Actually there are small differences in size of prism housings of various models as can be seen from table listing dimensions of various models. I did handle the 6x30 model ( and deeply regret not buying them too!). The were slightly smaller.

The 7x35 model's prism housing is similar in size and shape to comparable 7x35 one piece (B body) glasses of the same vintage. The major differentiation is in the top flange. The Ashahi Marine's flange is somewhat larger and held in place by six screws. See the attached comparison with a pair of Bushnell Featherlight 7x35 IF glasses. The Bushnell's prism housing is almost identical to the Asahi's but the top flange is fastened with only two screws and the eyepiece itself.

Charlie
 

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Charlie,
Thank you for this cool old ad, and your opinions. However undainty top class IF porros may be, yep, they are optically, if you are into alpha glass, sort of like, not something you really want to know about. But open your eyes, and there it is.

How do the PIFs figure in to this picture?
Ron
 
The Pentax Marines are not as good as the Fujinon stuff or the E series and later Nikon porros. They are better than the Nikon A series and prior. And generally better than the older Fuji stuff. About on par with the older classic style B&L Porros...though I favor the B&L porros....even the Japanese made Zephyrs and Discoveries over the Pentax Marine.

Pentax Marines are very good binoculars.
 
Thanks to your posts 9 years ago, I managed to get a Pentax Mariner 7x50 BIF on ebay Germany. It is very rare in Germany, Pentax had no market share here in the 70ies, the market was dominated by Zeiss and Steiner...

I will tell what it is like when I have it in hands.

Another link about this glass, which is produced not by Pentax itself (JB6), but by JB 2 = The Katsuma Kogaku Kikai Co.Ltd. according to this source. I will check if a JB number ist on my glass...

http://tedbrink.webs.com/japan21.htm
 
"The Pentax Marines are not as good as the Fujinon stuff..."

Methinks you might be surprised!

Bill
 
Glass has arrived, optics perpect, body some sign of use and needed some cleaning, but no dents and leatherette is still perfect. Might have been on a boats in its first life in the 70ies, as the front ring looks like it often stood on the front rings...

I am very pleased with the optics in may first indoor light test. Sharp to the edges and good color rendition. heavy (1300g) but a pleasant shape to hold. But I have not high end 7x50 here for comparison. Close focus is about 8/9 meters.

I had to pay 140 Euros, maybe a little high (due to obe other bidder, otherwise I would have got it for 90 Euros. But it is ultra rare here in germany, the next chance for it might be in years...

I am very pleased with it for collection as well as the intended use, e.g. owl watching and use (car based) whe my Kowa Prominar 8x33 will get low light problems. Or when travelling onboard a ship, sorry no own yacht...
I have a SUP, and therefore onboard I will get a as new used Fujinon WP-XL 7x50 Mariner which can swim, which is very important onboard a SUP...

Manufacturer JB 2 is confirmed, it is noted inside and can be seen through the front lens.
Glass has fix plastic eyecups, not suited for eyeglasses, which is luckily no problem for me. Maybe it gave special spectacle seyecups, the eyecups are screwed and easy to remove or change.

What do you think if such a vintage glass is still as waterproof as 40 years ago? Are the save ways to test this without ruining it when it is not waterproof any more?
 
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today I found that at least from the outer body design, the US WWII binoculars M15 Westinghouse or Bausch and Lomb or BL Mk28 look very similar! Typlical BL round shapes...

Maybe the US guys know more about this US Army glasses? Could the JB 2 producer habe any postwar licence of Bausch and Lomb or was the BL design only fancy?

Collimation test today of the Pentax mariner was perfect, and with some foggy weather today outside the vision was in transmission, clarity an sharpness on par with my Kowa Prominar 33. But weather did not give harsh contrasts for CA testings. My Kowa is a good benchmark for CA-free...
 
"B" Bausch & Lomb design/one-piece body
"IF" Individual Focus

Bill

Thank you. You think the design is reminiscent to a good design of Bausch and Lomb? As the japanese (Nikon) also did with the Contax cameras...

Unfortunately in Germany we know merely nothing about US binoculars...

BTW today I could get a M15 Westinghouse on ebay Germany (rare find, was not expensive, hope it is in aceptable shape, we will see...)
 
Thank you. You think the design is reminiscent to a good design of Bausch and Lomb? As the japanese (Nikon) also did with the Contax cameras...

Unfortunately in Germany we know merely nothing about US binoculars...

BTW today I could get a M15 Westinghouse on ebay Germany (rare find, was not expensive, hope it is in aceptable shape, we will see...)

We have seen that basic 7x50 carry the Nikon, Pentax, Swift, and Tamaya name along with dozens of others. The Japanese were great at reverse engineering.

Bill
 
Jan, what do you mean with "down here"?

And what Audubon 8.5x44 do you mean. The old ones or the newer ones with a kind of rubber armoring?

Hi Elmer,

Down here is just that BIG country between the North Sea and Germany.

What I mean is the Porro model which comes in the "old" model without and the latest model with rubber armoring. Especially the latest model with the orange ED label is favorit, but all three are popular.

Jan
 
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