J-12 and Kiev focus wheel?

[frederik@shaw.c]

I just got a Kiev 4a with J-8 and J-12 lenses and am putting the first roll of film through it. I'm puzzled about one thing. All the information I've come across says that the focus wheel only operates with the J-8 normal lens and not with the other lenses, which should be focused with the ring on the lens. However, the J-12 also seems to couple with the focus wheel. The only difference is that the infinity lock doesn't catch. Did the various instruction manuals leave something out? Thanks for any info.

 

[Ed S.]

The focus wheel can be used to focus other Kiev lenses, but it can be a bit painful. I usually rotate the lens barrel on my J-9 and J-11 to focus. Hand under the lens seems less likely to interfere with the rangefinder.

The focus lock makes connecting and disconnecting lenses much easier, as discussed at some length on an earlier thread in this section.

Rotate the mounted lens to infinity, then disconnect. Make sure the focus lock catches. The J-3, J-8, Helios-103 and Menopta are all 50mm lenses, and mount the same way. To mount a J-9, J-11 or J-12, set the lens to infinity, then mount.

 

[Highway 61]

The focus wheel does couple, and turn with all lenses though the friction is too great to use the wheel with any lens other than the 50mm. It's only with the 50mm that the infinity lock works too.

Well this matter has been discussed hundred of times either here or at the Zeiss Contax and/or Nikon RF forums and the proper answer is : the focus wheel does couple, and turns with all lenses though the friction is too great to use the wheel with any lens other than the 50mm and 35mm (and 28mm for the Nikon RF system). It's only with the 50mm that the infinity lock works too.

Given that both the camera body focusing helical and J-12 helical are cleaned off their congealed waxy cerumen-like stuff, and freshly lithium grease relubed.

In other words, if the camera focusing helical and J-12 helical both turn freely and without squeaks or binds, there is no problem whatsoever using the focusing wheel with the Jupiter-12, if this seems more convenient to the user.

Trying to use the wheel with the 85 and 135 lenses will just break the inwards focusing gears, and should never be done.

 

[frederik@shaw.c]

Thanks everyone. Sorry I couldn't find the info by searching.

 

[bolas]

It's possible to operate with the focus wheel but i've read somewhere that this can damadge the mechanism (because of neccesary force) - that's why one should use ring on lenses ...

 

[ErnestoJL]

The focusing wheel drives directly the moving prism assembly, it is, in the end of the mechanical linkage from the lens mount to the RF assy.
The normal lens rotates when focusing so it´s not an issue, however, all the other lenses be it WA or Tele, are mounted to the external bayonet, and are linked to the inner bayonet (that is part of the focusing helical) via a spring loaded tube. A minimal misalignment of the lens helical, or the lack of proper lubrication (two of the usually found problems in old lenses) leads to excessive force applied to the teethed wheels which transmit lens position to the moving prism. Then to avoid problems, the focusing wheel should be only used when focusing with the normal lens mounted.
I have one K4 with a damaged wheel for this reason.

Cheers

Ernesto