Leica Fake 5cm F2 Sonnars on Ebay, Jupiter-8 lenses with a Phony Name ring.



I've noticed many Ebay sellers putting Jupiter-8 lenses with phony namerings on Ebay at prices over $300. These are not pre-war 5cm F2 Sonnars converted to Leica mount. These ARE 1960s Jupiter-8 lenses with a fake namering.





These lenses are worth about $50.

Don't expect Ebay to stop these auctions, they are clearly counterfeit and the auctions are cons.

If you have any questions on any auction for a Sonnar lens, especially ones in Leica Mount, feel free to post here. I've taken many of them apart, know them inside-out. I've converted 70 or so to Leica mount. These lenses: they are Jupiter-8 lenses. Buy one for $50.

This one:


Is a J-8M. Worth about $20. I bought a couple for under $10.
 
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For reference:

50206417392_62aa2ec6ca_h.jpg
5cm F2 Sonnar, Converted to Leica Mount by fiftyonepointsix, on Flickr

This is a pre-war (1930s) Carl Zeiss Jena 5cm F2 that I converted to Leica mount using the focus mount from a 1950s Jupiter-8. The optical block is taken from the Contax collapsible mount and transplanted to the Jupiter mount.
Note the difference in the Namering, the font and finish of the ring is different from the phony Sonnars in the auctions linked to.

When you disassemble a Carl Zeiss Jena 5cm F2 made up until 1945, you will find the front glass stamped into fixtures, each with a Serial Number to match the last digits of the lens. SN on the front element, middle triplet, and rear doublet.


47300939811_9679a3221f_h.jpg
Clear_Rear_InPlace_Or_Unscrew by fiftyonepointsix, on Flickr

47300939691_f14bca8ef5_h.jpg
Optics_Out by fiftyonepointsix, on Flickr
 
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albertk

Veteran
This you has been going a long time: fake Leitz LTM lenses that are in fact for instance Industars, that won't even focus correctly.

The brutality: they don't even give an housing with correct flange distance and helix turning angle. Now that would be worth something. [As Skyllany showed]
 


I've noticed many Ebay sellers putting Jupiter-8 lenses with phony namerings on Ebay at prices over $300. These are not pre-war 5cm F2 Sonnars converted to Leica mount. These ARE 1960s Jupiter-8 lenses with a fake namering.





These lenses are worth about $50.

Don't expect Ebay to stop these auctions, they are clearly counterfeit and the auctions are cons.

If you have any questions on any auction for a Sonnar lens, especially ones in Leica Mount, feel free to post here. I've taken many of them apart, know them inside-out. I've converted 70 or so to Leica mount. These lenses: they are Jupiter-8 lenses. Buy one for $50.

This one:


Is a J-8M. Worth about $20. I bought a couple for under $10.

The first three have the same serial number. LOL
 
The fake Elmars: These are usually Industar-10 lenses. Often the F-Stop numbers on the Aperture and Depth-of-Field are different. F18 on the Aperture setting and F16 on the DOF. I have yet to see one with a re-engraved DOF scale.
 
This you has been going a long time: fake Leitz LTM lenses that are in fact for instance Industars, that won't even focus correctly.

The brutality: they don't even give an housing with correct flange distance and helix turning angle. Now that would be worth something. [As Skyllany showed]
I worked out the Math for changing the focal length and reshimming the lenses. some 15 years ago.


I've also shimmed the I-50 (collapsible), I-22 (Rigid and collapsible), I-26M, I-61L/D, J8, and J3 for the Leica.
The I-50 is the one to get for people wanting a cheap Elmar. It is actually based on the Tessar with the placement of the aperture, between 2nd and 3rd group. Elmar- aperture is after the front element.

The pre-war 5cm F3.5 Tessar is expensive, often more than the F2 Sonnar. The I-50 collapsible is Brass.


(Great article, be sure to read down to the last paragraph... )

I'm happy that Chris is offering this service, I refer people to him when getting a query for converting lenses. I'm also getting one of the first Bertele Sonnars and an Omnar converted Zeiss Opton 50/1.5. I'll be testing them and reviewing here when they arrive.
 
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The Math. Ended up doing Excel spreadsheets to convert focus error to change in shim thickness. Also to move optical groups to acheive better focus.
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