Räuber
Well-known
After hesitating for a long time I finally bought one Sonnar 5cm f/2 that I initially thought of as a fake Sonnar. I'm not convinced that this is fake anymore. It is more of a undocumented spare part Sonnar CZJ was building for the Zorki Jupiter-8 production. On the other side it is a quite strange one since it is using a geared head and an aperture scale only visible from the front and not from the side ( a design that was only used for one nickel Sonnar 5cm f/2 version 1934 ).

As you can see it is in a pretty beaten up condition. The body is missing. You have a M27 screw at the end of the lens to screw it into somewhere. It does not allow to use a filter or a lens cap. I would be thankful if someone can sheet some light on the purpose of this lens. Was this used for motion picture? Was this used for some kind of expedition or even war setup?
What convinced me that those lenses are actually CZJ Sonnars is the engraved serial at the rear end. All serials are authentic. And in the end KMZ never tried to fake the origin of the Jupiter-8 lenses. If KMZ build the lens they used the Jupiter-8 name. If they reused parts they mixed the Jena parts and the KMZ production parts but never engraved a name ring with Carl Zeiss Jena.

I have seen this lens in 4 forms yet.
My question is what is up with this head design? Why not use the head of the collapsible Sonnar f/2?

I got this other (collapsible) CZJ 5cm f/2 block stuck in a Contax Zorki body. The picture shows the collapsible lens block next to the geared lens block. They show the same design. The difference is the head. Thanks to this CZJ Zorki I could screw the geared block into the body.

But my geared block has some issues. That is where I need some help from all the Sonnar experts here. The geared part is loose. I can unscrew it from the lens. Funnily I can unscrew the rear part of the lens with the engraved serial too. You can see this here.

The block uses the same aperture mechanism as the previous collapsible lens block. There is a small screw that drives the aperture blades. Setting the aperture works.

I can adjust the geared head so that the F/2 marking connects with the open aperture. There is a small tactile bump when I do so too. But sadly when I close the aperture I can turn the ring further than F/22 and in the end I can screw the head until it will not turn anymore. But then the aperture mark is way off. And than the aperture does not work anymore. I can not open or close the aperture when the head is screwed tight. I'm not sure if all of this is wanted. Maybe they wanted to have a fixed position where you can not change the aperture anymore. Or maybe I need to fix it? Unscrew the head and reassemble it? Or does it miss a screw to fix the aperture ring? There are some screw holes below the geared part but there are no screws in there.
Can someone help me with this?


As you can see it is in a pretty beaten up condition. The body is missing. You have a M27 screw at the end of the lens to screw it into somewhere. It does not allow to use a filter or a lens cap. I would be thankful if someone can sheet some light on the purpose of this lens. Was this used for motion picture? Was this used for some kind of expedition or even war setup?
What convinced me that those lenses are actually CZJ Sonnars is the engraved serial at the rear end. All serials are authentic. And in the end KMZ never tried to fake the origin of the Jupiter-8 lenses. If KMZ build the lens they used the Jupiter-8 name. If they reused parts they mixed the Jena parts and the KMZ production parts but never engraved a name ring with Carl Zeiss Jena.

I have seen this lens in 4 forms yet.
- the naked form like the one I own
- the one with a Zorki body for LTM
- the one with a Zorki body for Contax
- one with a frame
My question is what is up with this head design? Why not use the head of the collapsible Sonnar f/2?

I got this other (collapsible) CZJ 5cm f/2 block stuck in a Contax Zorki body. The picture shows the collapsible lens block next to the geared lens block. They show the same design. The difference is the head. Thanks to this CZJ Zorki I could screw the geared block into the body.

But my geared block has some issues. That is where I need some help from all the Sonnar experts here. The geared part is loose. I can unscrew it from the lens. Funnily I can unscrew the rear part of the lens with the engraved serial too. You can see this here.


The block uses the same aperture mechanism as the previous collapsible lens block. There is a small screw that drives the aperture blades. Setting the aperture works.



I can adjust the geared head so that the F/2 marking connects with the open aperture. There is a small tactile bump when I do so too. But sadly when I close the aperture I can turn the ring further than F/22 and in the end I can screw the head until it will not turn anymore. But then the aperture mark is way off. And than the aperture does not work anymore. I can not open or close the aperture when the head is screwed tight. I'm not sure if all of this is wanted. Maybe they wanted to have a fixed position where you can not change the aperture anymore. Or maybe I need to fix it? Unscrew the head and reassemble it? Or does it miss a screw to fix the aperture ring? There are some screw holes below the geared part but there are no screws in there.
Can someone help me with this?
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