Leotax LTM Leotax - Topcor-S 5cm f/2 and Fujinon 5cm f/2

Leotax M39 screw mount bodies
I'm purely speculating of course. This is from the 5cm f/1.2:

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Topcor5cmf2 & Fujinon5cmf2 are very sharp. Pleasantly sharp, unlike stark/clinical sharpness of modern asph lenses.
Fujinon5cmf2.0: one in m & the other in feet:
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Topcor5cmf2.0- There are 4 versions available & are supposed to differ optically.
However, image rendition between Type 1 & 2 does not seem to differ.
All chrome is Type 1, chrome & black is Type 2, all black is Type 3 & 4. Shown here is Type 1 & 2 (I called it 'Panda' type):
3387366336_31e437de45.jpg


Topcor-S 5cmf1.5 (a half Sonnar). This is an improvement over the Simlar 5cmf1.5 which is a little softer.
Rendition of Topcor-S 5cmf1.5 is almost identical to Canon50mmf1.5.
See http://www.rangefinderforum.com/forums/showthread.php?t=69170&page=4 post #81 & #94
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I have sent an e-mail inquiry to Fuji HQ. in Japan to see if they have any information in their archives regarding the optical design, production numbers etc., of the Fujinon L lenses and I am hoping they might come forward with some information in due course.

That's great! Do share with us if you get anything.:)
Thanks.
 
Topcor-S 5cm F2

Topcor-S 5cm F2

I actually just was provided one of these (a Topcor-S 5cm F2 lens) by a colleague who is retiring, to either keep and use myself or trade or sell (and split the income). It has been attached to a Canon 7S. Someone at the local camera store is probably interested in buying the Canon.

As to the lens, it looks very clean and the glass looks to be in excellent condition. I need to get an m39 to micro 4/3 adapter for it to work on my Panasonic G1. From what I understand of its worth, I am inclined to sell it or trade, though.

There was another lens that came with the camera, a Canon Serenar 85mm f2 lens. It looks interesting, too, and from what I read can be a decent lens, but I am even more likely to sell or trade that one because of its weight.

Any advice you can provide to me would be appreciated. As you will see, I am brand new to this forum. My interest in rangefinders began in 1962 when my father bought me a Voigtlander Vitomatic II. I learned a lot about photography through that little camera, though honestly I was always frustrated at not having a zoom lens!
 
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I have sent an e-mail inquiry to Fuji HQ. in Japan to see if they have any information in their archives regarding the optical design, production numbers etc., of the Fujinon L lenses and I am hoping they might come forward with some information in due course.

Did you ever get a reply for this lens? Am curious myself.

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does anyone know much about the leotax leonon 50/2? Is it just the same optical formula as the topcor but with a different coating?
 
I have several Topcor 50/2 LTM lenses and the Leonon 50/2. The Leonon looks very similar to one of the Topcor lenses (ridged black barrel), but not exactly. The images produced look similar enough (i.e., Topcors are all very fine lenses, and so is the Leonon). Without any other information, I would guess that Tokyo Kogaku made the Leonon, and they made it with the same optical formula as the Topcors. The coating used would have been whatever was current at the time. (I don't bother with the color of coatings too much -- coating technology was always changing, and I'm quite color blind.)

Cheers,

David
 
Finally landed a topcor 50/1.5. :) A single bubble in the glass, but otherwise clean. And sharp. I look forward to trying it out ASAP.
 
I had Tokyo Simlar 50/1.5, Topcor 50/1.8, 50/2, 50/3.5 and Leotax Leonon 50/2

All of them are excellent performers!

The 50/1.5 formula is a bit strange. It has triplet which looks at Sonnar at the front half, but the rear group is normal Planar design. I think the Canon 85/1.5 also has similar design.

The other Topcor, Leonon and Fujinon 50/2 are Planar design. Very sharp indeed!

Topcor 50/1.5
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Topcor 50/1.8
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Topcor 50/2
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Leonon 50/2
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I had Tokyo Simlar 50/1.5, Topcor 50/1.8, 50/2, 50/3.5 and Leotax Leonon 50/2
The other Topcor, Leonon and Fujinon 50/2 are Planar design. Very sharp indeed!
Hello mrlazyli,
You say that the Fujinon 50/2 is a Planar design, do know anywhere were the Fujinon L lens diagrams are available?
I have a Japanese book series that introduces the LTM/M lenses (> 300 lenses)
 

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Hello mrlazyli,
That's great that you have such information.Does it say what design the 5cm f2.8 Fujinon is?.
Could you tell me if this book is still in print only quite a few forum members are interested in these vintage Japanese LTM lenses produced by Fuji,Topcon,Zunow etc., (forum members Hacker,tooffy etc.,and myself included) and information is very difficult to find even on the web.

As far as i remember, it is Tessar formula likes most 50/2.8, 50/3.5 lenses, but i lend that book to my friend so cannot be sure yet.
i think that book series is still available and there is a bookstore selling at Hong Kong
 
I've had a Topcor-S 50/2 for a while now, its a great lens, very sharp wide open which makes focusing a breeze on my NEX-7, its color is fantastic, its perfect for candid shots wide open, sadly I don't have anything online at the moment.

It's a real shame that Topcon don't still make camera lenses as they were a top quality manufacture as good as Zeiss or Leica.
 
Is the topcor-s50/2 radioactive?

Is the topcor-s50/2 radioactive?

Read about some radioactive lenses and topcor was mentioned but maybe not this model? I have one and its a beautiful rendering lens:)
 
my copy of the Topcor-S f2 5cm


Topcor-S f2 5cm
by Andreas, on Flickr


Topcor-S f2 5cm
by Andreas, on Flickr


Topcor-S f2 5cm
by Andreas, on Flickr


Topcor-S f2 5cm
by Andreas, on Flickr

7 elements, 10 aperture blades, weight 255 grams.
Love how the aperture ring feels, definite stops but smooth and light in movement, focus ring lightly damped turning 40 degrees from 1m to infinity, for me pretty much the lens whose handling I enjoy most.
I also like the photos it takes! My samples are all taken on digital cameras, if you don't mind that I may add some, here is the flickr folder: https://www.flickr.com/photos/kuuan/sets/72157644078970601
 
I just relubed my Fujinon-L 5cm f2 LTM, it was much easier than I expected.
As with many RF lenses the optics are held by a retaining ring at the rear, unscrew that CCW to separate the optics and helicoid.

Next is to remove the focus ring and a silver decorative ring, the decorative ring is unscrewed with a spanner that has pin ends, now there are 3-4 screws holding the focus ring to the helicoid (I made a few witness marks around the screws, not that it was required).

The helicoid is a solid hunk of brass that spins freely, a screw-pin stops rotation at infinity and at MFD, it sits in a cut-out section of a wall (it should be possible to shorten MFD using a file on the right side stop, I would investigate to see how much room the helicoid has before it bottoms out, from memory 3-4 more mm should be possible), unscrew the pin and mark the hole it comes from.

Next is another retaining ring, this keeps the helicoid in its place, CCW to remove it, the helicoid will now pull straight out.

Now the helicoid can be separated, but first you need witness marks, the outer section is the solid brass part, the inner serves 3 duties, 1) it has a tab to keep the inner helicoid from spinning when you focus, 2) it's the RF cam, and 3) this is what the optics is clamped to with the first retaining ring. I placed the tab at 12:00 and slowly unscrewed the brass outer till the 2 parts separated and marked the brass part in line with the tab.

I didn't see any adjustment for infinity or the cam, I assume that is done with the helicoid by advancing or retarding the helicoid 1 thread, and the shim that stayed with the optics.
 
Great lens you have...my Nicca MIOJ came with a Nikkor 50 f2 that focus to 1.5 feet but must weigh over 1 pound! Nicca are fine Japanese engineering art too.
 
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