Removing/identifying mold on a camera lens

[altim]

I found a 50mm 1.2 at a local antique shop for a good price, however it possibly has some mold on the rear element. I only had the time for a quick glance since the store was closing, but the rear of the lens was covered in a yellowish substance that looked like you spilled something and let it dry. There was also some yellow stuff growing on the light seal foam on the inside of the camera, above the mirror.

My question is, is it possible to have this cleaned off if it is mold? Obviously I'd like to add a 1.2 to my collection, it would be my first. Thanks guys.

 

[onepuff]

If it is very very cheap you could leave it out in direct sunlight for a few days to see if it kills it. Some people have reported lenses working satisfactorily with fungal remnants but if it is as bad an infestation of fungus as you say, I wouldn't hold out much hope. Whatever you do, don't keep it with your other cameras or lenses as the fungus can spread.

 

[Worker 11811]

Correct me if I am wrong but I understand that mold can destroy the coating on the lens.
If the lens is coated and the mold has destroyed the coating, no amount of cleaning will repair it. Only disassembling and recoating will restore it. Unless it is a rare and valuable lens, it might not be worth the cost.

I'm with onepuff. If the lens is cheap you could try to clean it. If you are not very successful you haven't lost much. You could still use it for parts to repair other lenses or you could simply use it for experimentation purposes.

Otherwise, find a better lens and save yourself the money and the trouble.

 

[altim]

They're asking about $150 for the set. Although the lens in good shape is probably worth 500, spending 150 for a useless lens and camera is definitely not cheap! Is there any test I can do at the shop to see how bad the fungal damage is? I am going to bring some lens cleaner and a flashlight when I go back (in case it just comes off easily..one can hope), I wasn't planning on much more.

 

[Worker 11811]

I don't know what lens, presumably on an SLR, would be worth but, depending on the model of camera and the condition it is in, you might not even get $150 for it on eBay.

I could not say with any authority that the lens is or is not worth $500.

Regardless, the merchandise is not in prime condition. Depending on the shop and the temperament of the owner, you could use this fungus problem as a bargaining plank.

Some antique shops will bargain. Some will not. I have gone into shops and seen Griswold cast iron skillets marked or more times their value. When I asked the owner, he basically said, "That's the price." I went down the street and bought the exact same type of Griswold skillet in better condition for half the price. On other occasions, when I went into the shop and asked the price, the guy basically said, "Make me an offer."
(P.S. I live in the town where Griswold cast iron skillets were once made.)

Bottom line: Don't be afraid to ask for a bargain and don't be afraid to walk out.

 

[Leigh B]

There's so much good used film equipment on the market now at fire-sale prices, ...
it's hard to justify buying damaged goods at any price.

If it's fungus, the lens is shot and can only be revived by replacing the affected elements.

Fungus lives on the magnesium fluoride coating. Its waste product is hydrofluoric acid, which etches glass.

Couple this with the fact that fungal spores can lie dormant indefinitely, and will infect other lenses in the vicinity, and you have a recipe for disaster. I wouldn't take fungus-damaged lens if somebody forced it on me.

- Leigh

 

[fstop]

Fungus/mold eats the coating, ruins the lens, Keep fungus infected lenses away from good lenses.
the only way to kill fungus is heat ( a lot of it) or alcohol.

 

[altim]

This fungus thing is starting to freak me out, but I always thought fungus looked sort of like roots growing across the lens. This looks more like an even coating of crud, although there could be some root-like tendrils underneath once I check it out with a flashlight. Would mold as opposed to fungus be more likely to have this appearance?

Unless this turns out to be easily cleanable or a tremendous deal I think I'll walk, I don't want to risk infecting my other film gear which is working quite happily at the moment.

 

[Leigh B]

The description does sound more like mold than fungus. However...

Any environment that is conducive to mold is equally conducive to fungus. They thrive under the same conditions.

Whatever it is, it doesn't belong there. You could ruin a lot of equipment trying to save some bucks.

- Leigh

 

[Vangrr]

It more depends on how far along the fungus is. Without seeing it, its hard to say but any older prime lens is a snap to get apart and completely eradicate fungus and grime inside. I've done it to a number of lenses, most recently my SMC 105mm 2.4 with little effort and amazing results. What 1.2 did you find?

 

[altim]

It is an SMC 50mm 1.2, I decided not to go back and check it out (about a 30 min drive). if it's still there next time I visit the store, I might make a lowball offer Thanks guys.

 

[Worker 11811]

Plus... If it is still there when you go back, you have another plank to bargain on: It's been there three months with no buyers.

 

[Steve Roberts]

I recently had to take my SMC 50mm f1.2 apart for fungus on several of the internal elements. It's not difficult, though there is a trick to removing the front element assembly should you need to. Email me for details if you should buy it and need them.

Living in warm, damp south west England, fungus in lenses and on slides is a way of life. As has been said dismantling fixed focal length Pentax lenses isn't too hard, though it sometimes necessitates making up some simple tools. The business of fungus affecting the glass permanently is IMHO much over-stated. I use carbon tetrachloride as both a cleaner and Killer, not forgetting to wipe every part of the lens before reassembly. The price seems pretty excessive for a lens with a known problem, but in view of the extent of the problem as I read it, are you sure it's mould/fungus and not coffee/beer/Coke that someone's spilled on it?

Cheers,

Steve

 

[John Koehrer]

I dunno, there's also a body involved, Which one? beats me. At $150 it's not a bad deal even if you have to spend another $50-$75 to clean it.

 

[altim]

To be honest I don't remember what the body was, it was probably an ME Super or K1000...something like that. It did have a digital back on it.