Swapping glass on Minolta Rokkor PF 58mm f/1.4 MCI MCII

[millenial]

Hello,

Long story short, I now have two versions of the Minolta Rokkor PF 58mm f/1.4, I have the MCI and the MCII version (identified by serial # and the focus ring hills and valleys design).

MCI version is clean, completely operational. MCII version (thought to be the best optically) has the aperture stuck wide open, and the focus ring isn't focusing. So...humor me...according to my research these lenses are exactly the same (except for the glass formula).

My intrusive thoughts are telling me to swap the glass and put the MCII glass onto the MCI body. Has anyone tried? Is there anyone to tell me this is not smart?

Thanks.

 

[Andreas Thaler]

Hello,

Long story short, I now have two versions of the Minolta Rokkor PF 58mm f/1.4, I have the MCI and the MCII version (identified by serial # and the focus ring hills and valleys design).

MCI version is clean, completely operational. MCII version (thought to be the best optically) has the aperture stuck wide open, and the focus ring isn't focusing. So...humor me...according to my research these lenses are exactly the same (except for the glass formula).

My intrusive thoughts are telling me to swap the glass and put the MCII glass onto the MCI body. Has anyone tried? Is there anyone to tell me this is not smart?

Thanks.

If you are ready to remove the glass from the defective lens, could you also try to get it working again?

Then, in the best case scenario, you would have two functioning lenses.

Personally, I would not sacrifice an intact lens.

 

[ic-racer]

I have done that a few times. One time to change scratched glass for clean identical glass from a Schneider to a Durst barrel for my enlarger.
The other to change separated elements for clean identical glass from Caltar to Horseman housings for Horseman camera. It was pretty easy, but neiter of those lenses had a focus helicoid.
I was lucky that in both cases my research indicating the lens elements would be the same was correct. In spite of the lens barrels having different branding and shape.

 

[Kino]

Hello,

Long story short, I now have two versions of the Minolta Rokkor PF 58mm f/1.4, I have the MCI and the MCII version (identified by serial # and the focus ring hills and valleys design).

MCI version is clean, completely operational. MCII version (thought to be the best optically) has the aperture stuck wide open, and the focus ring isn't focusing. So...humor me...according to my research these lenses are exactly the same (except for the glass formula).

My intrusive thoughts are telling me to swap the glass and put the MCII glass onto the MCI body. Has anyone tried? Is there anyone to tell me this is not smart?

Thanks.

I would think swapping the elements would be far harder than cleaning the aperture and helicoid of the frozen lens.

Maybe this will help...

 

[choiliefan]

Thanks for posting this video. I've one of these I'd like to free-up as well.
Also have an FD Canon SSC 50 which needs the same treatment but seems much more complicated to get back together once its apart.

 

[xkaes]

I would think swapping the elements would be far harder than cleaning the aperture and helicoid of the frozen lens.

Good point. Plus, even if the optical design of the two lenses is exactly the same, the width of the elements might be different, or the structure holding the elements together might be incompatible. Minolta was constantly making minor internal changes to their lenses -- even within the same series -- for various reasons.

 

[Kino]

Good point. Plus, even if the optical design of the two lenses is exactly the same, the width of the elements might be different, or the structure holding the elements together might be incompatible. Minolta was constantly making minor internal changes to their lenses -- even within the same series -- for various reasons.

Yes, in the opening of the video, the repairer discussed both variants and the fact that there are minor internal differences between the variants.

That alone would make me hesitant to swap out glass between versions.

 

[millenial]

Thank you all, I appreciate the input and the sharing of the video. I decided against swapping the glass. I am a beginner when it comes to taking lenses and cameras apart but I feel more confident in just taking out the glass as opposed to trying to fix/clean the aperture and helicoid.

 

[millenial]

If you are ready to remove the glass from the defective lens, could you also try to get it working again?

Then, in the best case scenario, you would have two functioning lenses.

Personally, I would not sacrifice an intact lens.

I'm going to try to get it working again, I am just worried of damaging this sweet lens more than it already is.