Contax Zeiss Lens users, does this 35mm f/1.4 MMJ look okay? Found a blemish

[Tony Yang]

Hey everyone! Been a long time lurker of this thread before I finally decided to pull the trigger and start building a set of Contax Zeiss lenses! I currently have the 28mm f/2.8 MMJ, 50mm f/1.4 AEJ, 85mm f/1.4 MMJ, 35-70mm f/3.4 MMJ, and 35mm f/1.4 MMJ. Blown away by the quality.


Anyway, I was hoping to get some second opinions though on the 35mm f/1.4 MMJ that I bought off eBay. The description said it had been professionally cleaned and was free of fungus, haze, or residue. However when I inspected it with a flashlight, I noticed some markings towards the front of the lens. Here are pictures:

https://flic.kr/p/V1vEps

Front of the lens with no flashlight - looks clear

https://flic.kr/p/W2Zxob
Looking through the front of lens and everything looks clear still

https://flic.kr/p/V1vHPU
Looking through the back of the lens, everything still looks good.

https://flic.kr/p/V1vFEy
Shine a light through the front, and the back looks fine with the exception of some dust.

Now here is where I see the problem:

https://flic.kr/p/W2Zvh7
When I shine a flashlight through the back of the lens, this mark shows up towards the front element in the center. I can't tell what it is. Is it haze? Residue? I don't believe it's fungus. When I shine a light at the front, everything looks fine.

https://flic.kr/p/VGEXdW

Here are some test images, where I was looking for the mark to show up.
Shot against a brightly lit white wall at f/16

Shot against a blue sky also at f/16

Another random test image:

So do you think I should return the lens?
Is that marking going to get worse?
Will I be fine if I take it to a professional cleaner?
Could my lens coating, micro-contrast, color, etc be affected in comparison to a clean Contax 35mm f/1.4?

Sorry for the long post, but I really want to get to the bottom of this!

 

[Brent G Miller Jr]

Contact Duclos Lenses in LA, they will tell you exactly what's going on what you need, if anything. They are FANTASTIC and I trust them to always be honest and knowlduegable about maintenance on lenses which is their primary business.

 

[Ilya O.]

Hi, Tony, just go and shoot! Forget about this, it shows zero presence in your test pics. At worse it could give some highlights glowing when too bright light is present in the frame, but who said that's bad?

At first I thought you got the optical glue separation, but it seems it's not since there is no glued elements in the front of your Distagon:

So it's just some oil evaporated from the grease base or somebody's left the smudge with the fingers when assembling. Not a fungus for shure.

 

[Brent G Miller Jr]

Ilya, with all due respect I don't entirely agree. The images above are reduced and compressed 1600x1200 images. Even if there was something to be seen in the footage, you wouldn't be able to tell in those images, but as a 2K or 4K mezzanine deliverable, it could be another story. And yes, blooming is always bad if it's not suppose to be there. If a lens needs maintenance, then it should have maintenance to perform optimally.

 

[Tristan Pemberton]

Tony doubled up and asked this same question in the Contax thread. It was discussed in more detail there.

The up shot is, he sent the lens back for a full refund and is looking for (or has found) a better copy.

 

[Ilya O.]

Brent, for sure you're mainly right It just depends...your know...

Tristan, appreciate your update here much. Tony did the right move with the sending back.