5CM F1.5 Sonnar with damaged front element

[Alberto G]

Hi all,
I was looking on the web for the production year of my CZJ 50/1.5 sonnar RF and I found your useful table.
It seems to me that my sample is what you call v3b ZJ CR cb, 1936-1939.
What is not matching is that you write that aperture can go further f/11 (up to ipothetic f/16) but in my sample it is not true.
Now I have to find out how to clean front lens from haze.
I know it is not a cemented element, so it should be possible.
At the moment I had no success, and an amount of haze is always there.

 

[Alberto G]

Yes, I already removed the front lens and tried to clean it, but maybe it has etched as you wrote.
Maybe in 90 years of cleaning.

 

[Sonnar Brian]

Yes, I already removed the front lens and tried to clean it, but maybe it has etched as you wrote.
Maybe in 90 years of cleaning.

View attachment 4856969View attachment 4856971View attachment 4856972

I would look for a replacement element- that looks like someone tried to polish it, but did not succeed.

 

[simonOWO]

Yes, I already removed the front lens and tried to clean it, but maybe it has etched as you wrote.
Maybe in 90 years of cleaning.

View attachment 4856969View attachment 4856971View attachment 4856972

Since it’s not coated, you could try to find someone locally who do polishing, I think it should not affect the optical performance if it’s not that deep (it seems)

I know somebody in my country who does this kind of business, that are optical manufacture companies who also accept private inquiries

 

[simonOWO]

Should we create a separate thread dedicated for repair and service of Sonnar?

It’s seems to be all over the place, and I also think posting a new thread for any little issue seems like spam.

 

[Sonnar Brian]

@rauber - if you want, I can move posts about repairs to another one of my threads. I have the "Tales from the Greasy Side".
Leaving it here- has one positive aspect, in that I've personally used elements and groups across v3 and V4 Sonnars, and various Jupiter-3's to repair damaged lenses. This went both ways, v3 Sonnar rear fixtures to repair a 1952 KMZ J-3- worked perfectly. Front elements from KMZ J-3 to repair v4 Sonnars, etc.

 

[Räuber]

I'm fine with moving those posts. As a German I like order. 😅 And I like that we can revive an old thread to new life.

 

[Sonnar Brian]

New thread created. For some reaspn the forum software is not allowing moves to existing threads.

SO- this front element needs to be replaced. A parts lens from SN ~175xxxx through to ~260xxxx would be preferred, as would be a matching version 3 Sonnar. I am being conservative on the SN, as v3 occurs before and after this range- but might be intermixed.

 

[Alberto G]

It seems to me that this group is really efficient.
I'm convinced I have to look for a new front element, but I think it could be hard to find.
In the meantime I will look for someone doing polishing here locally. Maybe it could solve the problem. Thank you very much.

 

[WoodallP]

There is this guy in Kyiv who looks serious:

Pardon Our Interruption...

I have never used him but he has good feedback (though much of it for other sales). I know there is a war on but I have received two packages from Ukraine to France recently without issue.

 

[simonOWO]

There is this guy in Kyiv who looks serious:

Pardon Our Interruption...

I have never used him but he has good feedback (though much of it for other sales). I know there is a war on but I have received two packages from Ukraine to France recently without issue.

100USD including recoating seems like a good deal

 

[Alberto G]

I'm trying to contact an optical company here in Italy. They should do it.