[Dlanor Sekao]

I have two of these F 35-70 lenses.
First has bad zoom ring but good glass.....works on macro only and wont zoom.
Second one has funky hair fungus inside but everything works just fine on a mechanical aspect....Fungus affects photos really bad.
I have partially disassembled and reassembled the first and just don't know if I can get one good lens or should simply deep six BOTH in the trash can and move on ?
Any help for these ?

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Last edited by Dlanor Sekao; 04-22-2015 at 09:18 AM.

[Adam]

This is the article section. I've moved your thread to the lens forum.

I would move on with these and see if you can find a better copy. These are fairly abundant and not very pricey

[Dlanor Sekao]

Thanks....I have a good copy but wanted a second. Both were covered by Ebay $$$ back guarantee so Im out nothing.
I just hate to deep six something that can be saved....or used....... By myself or anyone else.
I just don't know what to do ?? Its DIY or nothing as I wont pay for repairs. Anyone else ?

[jatrax]

If you are out nothing then send them back and move on. This is a very nice lens, but cheap and common as dirt. Life is too short to mess with things like this. Unless you are really into fixing up old lenses rather than shooting with ones that work. I've worked on a number of lenses and fixed most but you have to look at the time invested versus the return. These just do not cost enough or are not rare enough to be worth my time to fix. There are plenty of nice ones on the market.

Send them back, get a nice copy and move on.

[Dlanor Sekao]

If you are out nothing then send them back and move on. This is a very nice lens, but cheap and common as dirt. Life is too short to mess with things like this. Unless you are really into fixing up old lenses rather than shooting with ones that work. I've worked on a number of lenses and fixed most but you have to look at the time invested versus the return. These just do not cost enough or are not rare enough to be worth my time to fix. There are plenty of nice ones on the market.

Send them back, get a nice copy and move on.

They are running about $50 on ebay. I already got a refund for both and also have 1 good copy for one of my oufits , but wanted a second for the other.
I fix most of the K lenses but these are a different bird for me....Zooms and not primes so Im lost.
I like the challenge to a degree , but cant really find any info on repair ??? This is the first fungus issue encountered for me......lets see what comes up before I deep six them in the trash.....Thanks.

[antipattern]

Take the challenge, you can only learn! I had two CSJ Tessar 50/2.8 lenses, one with fungus, the other was in bad shape, too, though I forgot what it was. I took them apart, salvaged what's best, and managed to get one fine sample out of it. I also have a bag of Tessar parts leftover, that I cannot put together for the hell of it. But - I have one working lens.

Of course zooms are different, but if you can keep both copies for free, you might as well give it a try. Even if you can't fix them, you will have spare parts and knowledge that you can use for future projects.

Just make sure you are really careful when taking the lenses apart since the new plastic fantastic designs are more fragile. Maybe consider taking a video/step-by-step photographic tear down of at least once of the lenses, so you know how to put them back together.

The fungus looks very bad, like one of my Tessars'. Usually, a bath in light soap or lens liquid cleans off most fungus. However, not this time, since the fungus had eaten into the coatings.

So I guess you want to consider using the mechanics of one lens and the optics of the other to reassemble a working copy. But maybe you can already fix the stuck zoom by taking it apart and putting it back together again. Maybe it's just a grain of sand that got stuck in the mechanics. Also, when swapping lens internals, you can often exchange entire lens groups in one piece, which simplifies the process considerably.

[weijen]

From the looks of it, the fungus is very superficial. The fungus may look terminal, but I'm sure it did not eat into the glass yet. The haze looking layer is probably just moisture buildup. It's harmless to the glass. I've dealt with worse. The rear-most element can be easily removed. A wash and wipe is all it needs.

The front elements will pop out when you unscrew the retaining clip. There are there elements in the front group. In my case, it was not very tight and I managed to unscrew with just my fingernails. The rear element can be unscrewed by hand if I'm not mistaken. If I remember correctly, there are a total of seven elements in this lens. This is quite an easy lens to disassemble and reassemble.

Speaking from my own experience, the F 35-70 has a joined element somewhere in the center. If there is fungus growth is in between the binding compound of the joined element, then the lens is unusable. It will ghost at the slightest of direct lighting. If that's the case, list lens up on ebay as "parts or not working" with a description of "sold-as-is-i-don't-know-a-damn-thing-about-it"

Someone might want the lens for the little aperture click bearing

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Last edited by weijen; 03-23-2015 at 08:19 PM.

[narual]

did the seller not mention that there was a nascent civilization growing on the rear element? I'd be pretty annoyed if that showed up at my door.

[Dlanor Sekao]

did the seller not mention that there was a nascent civilization growing on the rear element? I'd be pretty annoyed if that showed up at my door.

The seller knew nothing except it looked mint and had no wear.....lol. If lens buying its best to buy from someone who has a slight clue to lenses or if they don't its just a crap shoot. He promptly refunded when he saw pictures and apologized that he had no idea how to even remove the lens. No biggie.

---------- Post added 03-24-15 at 05:11 PM ----------

From the looks of it, the fungus is very superficial. The fungus may look terminal, but I'm sure it did not eat into the glass yet. The haze looking layer is probably just moisture buildup. It's harmless to the glass. I've dealt with worse. The rear-most element can be easily removed. A wash and wipe is all it needs.

The front elements will pop out when you unscrew the retaining clip. There are there elements in the front group. In my case, it was not very tight and I managed to unscrew with just my fingernails. The rear element can be unscrewed by hand if I'm not mistaken. If I remember correctly, there are a total of seven elements in this lens. This is quite an easy lens to disassemble and reassemble.

Speaking from my own experience, the F 35-70 has a joined element somewhere in the center. If there is fungus growth is in between the binding compound of the joined element, then the lens is unusable. It will ghost at the slightest of direct lighting. If that's the case, list lens up on ebay as "parts or not working" with a description of "sold-as-is-i-don't-know-a-damn-thing-about-it"

Someone might want the lens for the little aperture click bearing

The fungus was between the center elements too I managed to get everything swapped out and cleaned , but the helicoid is a bear getting in the right direction. Enough for tonight as this simply isn't worth hours of frustration.....one of these days I will learn.....lol.

---------- Post added 03-24-15 at 05:14 PM ----------

Take the challenge, you can only learn! I had two CSJ Tessar 50/2.8 lenses, one with fungus, the other was in bad shape, too, though I forgot what it was. I took them apart, salvaged what's best, and managed to get one fine sample out of it. I also have a bag of Tessar parts leftover, that I cannot put together for the hell of it. But - I have one working lens.

Of course zooms are different, but if you can keep both copies for free, you might as well give it a try. Even if you can't fix them, you will have spare parts and knowledge that you can use for future projects.

Just make sure you are really careful when taking the lenses apart since the new plastic fantastic designs are more fragile. Maybe consider taking a video/step-by-step photographic tear down of at least once of the lenses, so you know how to put them back together.

The fungus looks very bad, like one of my Tessars'. Usually, a bath in light soap or lens liquid cleans off most fungus. However, not this time, since the fungus had eaten into the coatings.

So I guess you want to consider using the mechanics of one lens and the optics of the other to reassemble a working copy. But maybe you can already fix the stuck zoom by taking it apart and putting it back together again. Maybe it's just a grain of sand that got stuck in the mechanics. Also, when swapping lens internals, you can often exchange entire lens groups in one piece, which simplifies the process considerably.

Everything went real smooth until it was time to install the helicoid back on......I just cant quite get it right. I had to quit for the evening.

[Dlanor Sekao]

I did finally manage to get one good lens out of the two. However it was the assembly of the helicoid that slowed me down and gave me fits. Took 5 hrs of repeated trying to do it. The lens is now de-clicked but works great on A setting. Fungus had etched the rear coating bad and was also between the middle elements which I could not clean.
Was it worth it ? Yes and No.......too much time spent , but now have parts and experience if I ever find a afflicted one again.

[reeftool]

You can probably find a decent used F 35-70 for considerably less that it will cost to repair either.

[weijen]

I did finally manage to get one good lens out of the two. However it was the assembly of the helicoid that slowed me down and gave me fits. Took 5 hrs of repeated trying to do it. The lens is now de-clicked but works great on A setting. Fungus had etched the rear coating bad and was also between the middle elements which I could not clean.
Was it worth it ? Yes and No.......too much time spent , but now have parts and experience if I ever find a afflicted one again.

Great job! I hope you took pictures along the way so you can share with us here.