Mamiya RB/RZ apochromatic (APO) lenses and repair guide

[zoo]

The Mamiya APO lenses (K/L and Sekor Z) are excellent but it is difficult to find them in good condition. Unfortunately, many of the ones that come up for sale have issues such as haze or balsam separation.

Defective copies are relatively cheap and can be restored to their original condition with only a few hours of work (and extreme care and patience).

I've published some commentary and a DIY repair guide here: https://zv.io/blog/mamiya-apochromatic-lenses/

There are a few open questions, such as which specific glass elements from the K/L and Z versions are/not interchangeable.

 

[kenny63]

hello, hi . Dear sir
I am new to this forum. and if I can ask question about the MAMIYA RZ lens 100-200mm F 5.2 zoom.
i bought it to use with FUJIFILM GFX with a fotodiox mount
however, I cannot stop down the aperture in mechanical way or by pushing some buttons.
only able to push the depth of field lever manually to get to the aperture we want
just wonder if this is the only way or I am wrong in few steps
Please help anf thank you
kenny

 

[zoo]

hello, hi . Dear sir
I am new to this forum. and if I can ask question about the MAMIYA RZ lens 100-200mm F 5.2 zoom.
i bought it to use with FUJIFILM GFX with a fotodiox mount
however, I cannot stop down the aperture in mechanical way or by pushing some buttons.
only able to push the depth of field lever manually to get to the aperture we want
just wonder if this is the only way or I am wrong in few steps
Please help anf thank you
kenny

I have no personal experience with that adapter but a quick search online reveals this review which seems to suggest there is a solution.

 

[kenny63]

Dear Zoo
thank you anyway and lets study more and revert
Kenny