f1.5 5cm prewar, uncoated oil on blades?

[jano]

I just received my Contax II with 5cm Jena f1.5 lens. The lens has a small nick on the front element, and some of the aperture blades look greasy or kinda wet. This grease.. is that "oil on the blades" ? Is it harmful?

Thanks,
Jano

 

[dexdog]

The oil on the blades is not harmful per se, but is often indicative of separated grease/oil spreading to the lens surfaces, and adversely affecting the photos. I have few lenses like this, and some perform well, and others do not. I would suggest shooting a roll and seeing what happens. A CLA on this lens will probably run $125 or so, sometimes less, depending on where you go.

 

[jano]

Thank you. The lens was purchased through a person who does CLA's and then ebay's the lenses, I forgot to mention that! Apparently has a decent reputation.

 

[David Murphy]

If it's not causing haze you are fine -- no compelling need to have it serviced. If there had not been some oil, the blades would probably have been frozen by now anyway. It sounds you like have a pretty good lens and I predict it will take stunning photos - enjoy it.

 

[David Murphy]

Thank you. The lens was purchased through a person who does CLA's and then ebay's the lenses, I forgot to mention that! Apparently has a decent reputation.

If he left visible oil on the aperture blades, then he did not service it properly. My guess is that he judged this not worth the effort if the lens lacked internal haze or significant fungus (both compelling reasons to open one up).

 

[jano]

If it's not causing haze you are fine -- no compelling need to have it serviced. If there had not been some oil, the blades would probably have been frozen by now anyway. It sounds you like have a pretty good lens and I predict it will take stunning photos - enjoy it.

Thank you. I am a wee bit concerned about the nick in the front element. I can see its reflection in the second element, too. Lens was advertised free of scratches.. and, indeed, it is free of scratches, but has one nick 🙄 I'm not sure whether I should contact the seller about this? It's just that he's located overseas.

Oh, by the way, what size filter goes on this? I need a lens cap or UV filter.

 

[dexdog]

The uncoated pre-war CZJ lenses are definately my favorites users. I have a number of Contax I and II lenses that I use on a regular basis. Great OOF areas, and they display a distinctive charm in the way that the photos are rendered. Originally developed for B & W film, the results are equally pleasant with modern color films too.

 

[dexdog]

Oh, by the way, what size filter goes on this? I need a lens cap or UV filter.

The lens accepts 40.5 mm filters, and 42mm slip-on lens CZJ caps. Of course, with old uncoated lenses, hoods are usually beneficial. eBay sellers such as heavystar and american eagle (I think that this is the correct name) sell fine quality vented hoods in 40.5m size.

 

[David Murphy]

Thank you. I am a wee bit concerned about the nick in the front element. I can see its reflection in the second element, too. Lens was advertised free of scratches.. and, indeed, it is free of scratches, but has one nick 🙄 I'm not sure whether I should contact the seller about this? It's just that he's located overseas.

Oh, by the way, what size filter goes on this? I need a lens cap or UV filter.

A nick in the front element is extremely out-of-focus and I think very unlikely to cause you a problem. I'd be thrilled to have a Sonnar as good as the one you are describing !