Cleaning a Flektogon 35mm (chrome barrel) ... (1/3)

... Be careful: not for the fainted of heart ...

At first, apologies for the multi-part post, but i have to cope with the 6K characters Blogger limitations ...

A few months ago, i got a Carl Zeiss Jena Flektogon 35 f/2.8 (the chromed one) in "mint condition" from an eBay seller. As soon as it arrived, in its original box, i inspected it visually and noticed nothing, no fungus/haze, or oily diaphragm blades. Being busy professionally (i just finished the training for my new job), i decided to try it on the camera later ... Useless to say, i was really disappointed when i took my first shots, seeing a yellowish haze on the pictures i was taking during a "Flektogon vs. Flektogon" match (yes, i have both the 35 f/2.4 and the f/2.8 chrome) ...

An orchid phalaenopsis shot by the MC Flektogon 35 f/2.4 (the black one) stopped down to f/16, in halogen light:


The same flower, shot a few minutes later, under the same lightning conditions, with the Flektogon 35 f/2.8, the chrome one, stopped down to f/16 too:


It's easy to detect the brown-yellowish haze and the lack of details ... Sure, the chrome is older than the black one, but i wasn't expecting such a difference and, before complaining with the seller, who already sold me other good lenses, i decided to inspect better the lens using a spot light (be careful to your eyes if you decide to try this), and noticed a kind of irregular haze inside (sorry, don't have a lens to picture this, but it looked as an irregular film of grease or dust).

So, after spending some of my free time searching for repair tips, i asked on a forum for help. Unluckily, i received almost no replies, except one with a link (http://rick_oleson.tripod.com/index-81.html) to some handmade sketches of Zeiss lenses (still, no luck, just Biotar and Tessar, indeed a very very helpful sketches, as i will realize later ...).
After a month of no replies (and no further information found), i decided to try to fix it myself, since it would have been too expensive to use the services of a professional repairman (after all, i had the lens for a few euros, these Flektogons are much cheaper than their black f/2.4 counterparts, which sell for +100 euros).

Taking advantage of the last long weekend (five days in France, from 8 to 12 may), feeling comfortable after fixing my Takumar 24, i decided that it was time to give a chance (the last one ?) to my Flektogon chrome.

Little disclaimer before going on: I ASSUME NO RESPONSIBILITY IF YOUR LENS BECOMES USELESS AFTER THIS INTERVENTION.
I have tried to do my best in documenting how to open the lens, but i don't know if i did it the right way. Keep in mind that there are some (a lot of ?) professionals out there that can service these lenses far better than me ...

If you decide to go on anyway, here is the whole story ...

At first, the required tools:
- A pick tool, to clean the filter screw mount
- A lens ring tool, to remove the front name ring
- A spanner wrench
- A micro-fiber cloth
- An optical lens cleaning fluid
- Zippo fuel
- Some WD40 (or the like) to lubricate the filter thread (if required)
- A plastic box for parts
- A clean surface

With all this gear ready, you can go on.

1. The picture of the patient, a mint Flektogon 35 f/2.8 with its caps and original box:


2. Front view, just in case a RIP tombstone would have been necessary after the surgery ... (don't blame me, it's the post-surgical stress falling down ;-) ...)


Be sure the filter thread is clean, check by screwing in a 49mm filter. If required, clean the thread with the pick tool, or a cheaper tooth picker ...

3. Remember the sketches from Rick Oleson (link above)? By looking at them i understood i had to start from the front side, so i prepared the tool for the name ring removal, the (now) classic multi-sized basin cap ...


4. Starting to unscrew the name ring (i had some WD40 ready just in case, but it has not been necessary ...)


5. Name ring removed ... First scary vision: two rings with marks for a spanner wrench ... Which one to unscrew? Again, remember the sketches from Rick Oleson (link above)? I went for the outer one ... and did the right choice!


6. Spanner wrenches are really hard to find in France and expensive (i know Micro-tools, maybe i will buy one later, i'm not a pro ...), so, in the same "more-for-less" spirit of the basin cap, i bought the "poor man spanner wrench" ... a stainless steel compass, for 8 euros ...


End of part one. Click here for part two ...