cleaning a foggy lens

[-vin-]

Have you ever tried doing it yourselves? Have you ever had a lens with fog and/or fungi, and decided to open it? And if the answer is yes, were you successful?

(ok, let me know how much does a good lens cleaning cost...)

 

[cpborello]

Are you in the US? If so, I understand that Golden Touch (Sherry Krauter) does a nice job for $75-$150 (depends on the particular lens). I have only used her for camera CLAs, but was satisfied.

 

[ferider]

It's like mushrooms - you take the ones you know, the others you
leave (i.e. send to DAG or Sherry).

What lens are we talking about ?

Roland.

 

[-vin-]

It's like mushrooms - you take the ones you know, the others you
leave (i.e. send to DAG or Sherry).

What lens are we talking about ?

Roland.

I'm in the EU, not in the US...

And I don't know any lab with a reputation as good as the one of Sherry Krauter. The lens is not a really valuable one: it's a canon 50/1.8.

 

[ferider]

A foggy Canon 50/1.8 is fairly easy to clean. Most likely the fog is on the surface directly behind the aperture blade.
You can check this visually by looking through the lens from the front at a light source and closing the aperture.

If this is true, buy yourself a lens spanner, and

- take the barrel off the focus mount (by unsccrewing the large ring from the back)
- take the rear optical block off (another span ring)

Then you can clean the dirty surface. Do this with a good cleaning cloth,
micro-fiber, or similar.

Then put back together the other way around. Your risk of course.

Newer Canon 50s can also be disassembled from the front. If you have
a black 50/1.8, there should be a tiny screw in front of the aperture
ring. If you take this out, you can unscrew the entire front block
and get access to the above element surface.

(I've cleaned multiple Canon lenses successfully. They are relatively easy since
the coating is pretty hard).

Fungus you have to treat a little differently. Clean thoroughly, discard the cleaning cloth
and expose the open lens to light for a couple of days).

Hope this helps.

Roland.

 

[-vin-]

A foggy Canon 50/1.8 is fairly easy to clean. Most likely the fog is on the surface directly behind the aperture blade.
You can check this visually by looking through the lens from the front at a light source and closing the aperture.

If this is true, buy yourself a lens spanner, and

- take the barrel off the focus mount (by unsccrewing the large ring from the back)
- take the rear optical block off (another span ring)

Then you can clean the dirty surface. Do this with a good cleaning cloth,
micro-fiber, or similar.

Then put back together the other way around. Your risk of course.

Newer Canon 50s can also be disassembled from the front. If you have
a black 50/1.8, there should be a tiny screw in front of the aperture
ring. If you take this out, you can unscrew the entire front block
and get access to the above element surface.

(I've cleaned multiple Canon lenses successfully. They are relatively easy since
the coating is pretty hard).

Fungus you have to treat a little differently. Clean thoroughly, discard the cleaning cloth
and expose the open lens to light for a couple of days).

Hope this helps.

Roland.

Thank you for the suggestion, Roland! It doesn't seem really difficult, maybe I could try...

 

[vicmortelmans]

Fungus you have to treat a little differently. Clean thoroughly, discard the cleaning cloth
and expose the open lens to light for a couple of days).

Roland.

Hi Roland,

what's the idea behind this? Isn't fungus something organic 'growing' on the coating? Is ithe UV that's killing the fungus?

I've once opened a jupiter 8 of which the interior side of the front element was infected by---what I thought was----fungus. I subsequently attacked it with dry cloth, generic cleaning fluid, alcohol and aceton. Only the last product was able to remove the fungus (and probably the coating as well, if this lens has one ).

Groeten,
Vic

 

[ferider]

Hi Vic,

when it grows for a while is can etch the coating, and
you can only remove the traces by removing the coating as well
Only in the early growth stages can you remove it completely.

It grows in the dark, and gets killed by UV. Remaining spores might
make it grow back or even, supposedly, "infect" other lenses.

I also think that storing old lenses in their original leather cases
promotes fungus growth.

Nasty stuff.

Roland.

 

[Kim Coxon]

The problem is not the coating but the glass itself. Some few strains of the fungus an acid as a by-product and this eats glass. Even a re-coat will not cure it.

Kim

Hi Vic,

when it grows for a while is can etch the coating, and
you can only remove the traces by removing the coating as well
Only in the early growth stages can you remove it completely.

It grows in the dark, and gets killed by UV. Remaining spores might
make it grow back or even, supposedly, "infect" other lenses.

I also think that storing old lenses in their original leather cases
promotes fungus growth.

Nasty stuff.

Roland.

 

[Kim Coxon]

Whereabouts in the EU? I may know someone who has worked on these.

Kim

I'm in the EU, not in the US...

And I don't know any lab with a reputation as good as the one of Sherry Krauter. The lens is not a really valuable one: it's a canon 50/1.8.

 

[hans voralberg]

I would be interested to hear Kim

 

[meven]

Hi,

Anybody know how to clean a Rigid Summicron by any chance?

Cheers
Max

 

[literiter]

This is general but I can make a few small suggestions.

-some inner coatings of some lenses are coated with material that can come off by gentle rubbing. Be very cautious about cleaning the inner surfaces on some lenses. Zeiss lenses used on Super Ikonta lenses can have this issue. I don't know about Leitz glass but be cautious. If you damage the inner surfaces of your lens you'll be royally pissed.

-A 50/50 mixture of good houshold ammonia and hydrogen peroxide, when fresh works often on fungus. Must be a fresh mixture it seems. I have painted the stuff on with a soft (#8) artists paintbrush, then shaken it off gently. I'll then clean with pure isopropyl alcohol.
As stated very well earlier, if the fungus has etched the glass, you'll have to live with it.

 

[meven]

Just for your information, I found this interesting web page:
http://www.mypentax.com/Fungus.html

 

[Keith]

I had a very foggy 35mm Summaron f3.5 that I sent to a tech here in Oz for cleaning. He had it for three weeks then returned it to me because he couldn't get it apart! I was sending a camera to Youxin so I put the lens in with it and he forwarded it to DAG when he received it. I haven't seen the lens yet but Youxin tells me it looks like new and DAG charged $50.00 for the work which is great because I've heard that these paticular Summarons are indeed very hard to get apart without breaking the front element!

 

[Kim Coxon]

I will second this especially for Leica Lenses. As I learnt from Peter at CRR ( ), it is very important to only "wet" clean them. If you try to "polish" them with a dry cloth, there is not only the danger of dammaging the coating but it also makes any haze harder to remove.

Kim

This is general but I can make a few small suggestions.

-some inner coatings of some lenses are coated with material that can come off by gentle rubbing. Be very cautious about cleaning the inner surfaces on some lenses. Zeiss lenses used on Super Ikonta lenses can have this issue. I don't know about Leitz glass but be cautious. If you damage the inner surfaces of your lens you'll be royally pissed.

-A 50/50 mixture of good houshold ammonia and hydrogen peroxide, when fresh works often on fungus. Must be a fresh mixture it seems. I have painted the stuff on with a soft (#8) artists paintbrush, then shaken it off gently. I'll then clean with pure isopropyl alcohol.
As stated very well earlier, if the fungus has etched the glass, you'll have to live with it.