[Tinus]

Hi all, I just joined this forum and straight from the start I have a big thing (at least big for me) with which I would like your help!

I recently bought a batch of old m42 lenses for about 25 euro's. I was looking for an 28mm 2.8 and the batch had a pallas auto 28mm 2.8 lens + a pentacon 50mm 1.8, a pentacon 200mm f4 (15 blades version) and a Carl Zeiss Jena 135mm 3.5 MC (sonnar). All lenses are physically in great condition and look/feel like good quality, solid lenses. I especially love the look and feel of the Carl Zeiss Jena! Of course they each have a bit of dust on the inside, but not so much that they are no longer worth it.


However, the Carl Zeiss Jena lens is in critical condition. It's filter thread is dented, the diagram is stuck and there is some fungus visible on two or three elements. From what I have read, this lens can be amazing. Sadly the current condition obviously leaves the lens working at only a small percentage of its potential. See Images for details.


One of the purposes that I would like to use this lens for, is to use it as a tube lens for a macro set up. I have read that it delivers very well in this aspect. I naturally also want to use it for other things than just macro.


So my question is, do you have any tips for me as to fix this lens? I am relatively new to these lenses, so I am afraid to open it up and possibly do more harm than good. But it's a waste to just let it gather more dust in my cabinet. Any help will be greatly appreciated!

Thank you very much in advance!

Attached Images

     

[marcusBMG]

here's how to fix the dent in the filter ring (pics are missing but description/discussion is sufficient ;

Easy filter ring dent removal TTP with photos.

To disassemble the lens to clean the optics you wil need a lens spanner. FYI:

Basic techniques to repair lenses (and cameras)

[torashi]

I would recommend a filter ring vise and help from someone with experience. Way better than using a hammer. A clean and illuminated workplace with grooves to hold rolling screws, springs and lens elements. And a good set of tools and supplies: Isopropyl alcohol and disposable, lintless lens wipes. Vinegar or bleach to kill the fungi and distilled/deionized water to wash the affected parts thoroughly. Cleaning and applying some special lens helicoid lube wouldn't be a bad idea either.
Take pictures of all the steps so you remember how to reassemble everything.
Or just take it to a good repairman.

[Tinus]

Thank you for your repsonses, I have taken the lens apart to get an idea of the situation. It seems like the front element and the back element are set with fungus. Disassembling the diagram is going to become tricky, but otherwise the disassembling is not very complicated. I can easily remove the back element and I think the front element won't be hard either. I can get the filter ring apart from the lens body and elements, so I would feel safe using both methods of fixing the dent. What is the difference between the hammer and the vise method? Is one safer than the other?

here's how to fix the dent in the filter ring (pics are missing but description/discussion is sufficient ;Easy filter ring dent removal TTP with photos.To disassemble the lens to clean the optics you wil need a lens spanner. FYI:Basic techniques to repair lenses (and cameras)

I will take a good look at that guide and see wether I will use the hammer or the vise technique. I actually do have a lens spanner, just not a lot of space to carefully go to work (I am a student, in a small student room). But I will be moving soon to a somewhat larger living quarters, so I will try my luck there.

I would recommend a filter ring vise and help from someone with experience. Way better than using a hammer. A clean and illuminated workplace with grooves to hold rolling screws, springs and lens elements. And a good set of tools and supplies: Isopropyl alcohol and disposable, lintless lens wipes. Vinegar or bleach to kill the fungi and distilled/deionized water to wash the affected parts thoroughly. Cleaning and applying some special lens helicoid lube wouldn't be a bad idea either.Take pictures of all the steps so you remember how to reassemble everything.Or just take it to a good repairman.

Do you have any tips on household cleaning items I can use to clean/relube the lens? I read that vinegar can damage the coating of a lens, is this true? If yes, are there other methods of cleaning the fungus off?


Sorry for the huge ammount of questions, but I would love to do this myself and to do it as well as possible.

[marcusBMG]

Do you have any tips on household cleaning items I can use to clean/relube the lens?

I use a tissue moistened with household mould remover. Basically any detergent kitchen cleaning spray will do great. Then wipe off with an optical wipe, finish with a lens pen. Coatings aren't damaged by these or any of the usual cleaning solvents like alcohol, acetone, ether etc. It's actually very difficult to avoid slight smears, wipe marks that are detectable when the optics are reassembled (not that they really matter).

A filter ring vice is good if you can get hold of one the right size, I use the small hammer and hardwood tamp method, works fine I've straightened out numerous lenses (pic below of what was a bad one, a big indentation was at five-of position by ref number and this big old tokina is thicker metal), just be judicious.(gentle wee tap with the hammer, inspect, up the force incrementally). It is next to impossible to get the filter ring back to perfectly round, the metal will have been stretched slightly, the goal is round enough that the filter screws on/off, the nameplate screws on/off.

[torashi]

If you search "lens filter ring vise" on TheeTube a few instructional videos appear of people fixing their filter rings with such vises. I bought mine from the fleaBay, too, sent from China. Should set you back about twenty something USD, and should last for all the filter rings you'll ever need to fix in your lifetime.
Coatings don't get damaged so easily, that's why I recommend the wash with a good amount of distilled/deionized water after the cleanse.

[Tinus]

Thank you both again for sharing your tips and knowledge, I feel much more confident trying to fix this lens!

I use a tissue moistened with household mould remover. Basically any detergent kitchen cleaning spray will do great. Then wipe off with an optical wipe, finish with a lens pen. Coatings aren't damaged by these or any of the usual cleaning solvents like alcohol, acetone, ether etc.

If you search "lens filter ring vise" on TheeTube a few instructional videos appear of people fixing their filter rings with such vises. I bought mine from the fleaBay, too, sent from China. Should set you back about twenty something USD, and should last for all the filter rings you'll ever need to fix in your lifetime.Coatings don't get damaged so easily, that's why I recommend the wash with a good amount of distilled/deionized water after the cleanse.

Good to know that coatings aren't too fragile and that there are a lot of household cleaning products that will do the job. I will consider buying a vise, since I am really liking this project and am thinking about fixing up more lenses. I am gathering the other materials now and will start my project as soon as I am done moving.


One last question though; should I distill water myself or can I buy that at a supermarket as well? If the first option is the best, what is a good way to distill water? (Without a chemistry setup ;p)

[torashi]

I would rather buy distilled/deionized water from the hardware store, like the one you use for topping up car batteries.
One option is to use the one your clothes drier collects. It's not a guarantee that it is completely pure, but at least it's not caulky tap water.

[Tinus]

Alright, I found a place nearby where I can buy deionized water, so that part is covered. I ordered some new microfiber cloths for this project, since my current ones are pretty worn out from cleaning the outside of the lenses. The requirements are coming together and I am getting more and more exited for this project. Thank you both very much for your help, I will post the result in this post as well.

[Tinus]

Alright, I found a place nearby where I can buy deionized water, so that part is covered. I ordered some new microfiber cloths for this project, since my current ones are pretty worn out from cleaning the outside of the lenses. The requirements are coming together and I am getting more and more exited for this project. Thank you both very much for your help, I will post the result in this post as well.

Quick update, I fixed the stuck aperture and the dented filter thread see the attached file. I ended up using the hammering method, it worked great and I felt relatively comfortable with it. The aperture was just stuck and after adding just a bit more pressure on the aperture blades, they clicked into the proper position. Thats two problems down, one to go. Probably the biggest and baddest problem I got, the fungus!


I am still waiting for some of my cleaning solutions and cloths, then I will be ready to tackle the fungus. I got a 3% solution of hydrogenperoxide to clear the fungus. I am very much exited about this and am eagerly awaiting my coupling adapter. So that I can use the 28mm lens I got reversed onto this lens.

[torashi]

Nice to see some progress. I hope you get it working 100% in no time.

[Tinus]

Another quick update, one of the less positive kind however. I let the lens rest in the window, so the uv rays can kill the fungus. However after about half a day in the sun, the focussing mechanism is extremely heavy now. Before I put it in the window, the mechanism was very smooth. Any ideas on how I can fix this issue?

Thank you in advance!