Fungus removal post!

[richardHaw]

http://richardhaw.com/2016/03/27/repair-fungus-cleaning/
Hi! please share your fungus removal routine so i can add it to this post (with credits). this will be a nice place to collect tried and tested fungus removal techniques.

[Bjørn Rørslett]

Lots of good advice here.

"Tendrils" is not commonly applied as a name for fungal hyphae though ... although I understand why it is being used.

[richardHaw]

Lots of good advice here.

"Tendrils" is not commonly applied as a name for fungal hyphae though ... although I understand why it is being used.

Thanks! I went to dental college but sucked at biology hahaha
dental anatomy is my best, i got a perfect score.

[Andrea B.]

Good column, Richard. And timely for me as I just discovered a bit of fungal growth in one of my rare UV lenses. These lenses tend to be rather overpriced and extremely hard to find so I hate to see such a lens go bad. I was successful in taking the lens apart and putting it back together. So now I'm going to take it apart and remedy the fungus problem a bit more thoroughly than I did the first time through.

Rechargeable desiccant canisters are my recent investment. One is stored with each rare UV lens now. These plastic canisters full of desiccant beads turn pink when they need to be dried out. Three minutes in the microwave returns the beads to their dry, dark blue colour. They are also available in a metal canister for recharging in a conventional oven.

BTW, I thought we were not supposed to mix hydrogen peroxide with vinegar??

Vinegar may clean the lens element but neither vinegar nor alcohol will kill fungus but I don't think vinegar will kill fungus? Ammonia is probably the best choice because it is alkaline. But I don't know what that will do to lens coatings?
I don't know at all about hydrogen peroxide.

[Bjørn Rørslett]

Hydrogen peroxide is a powerful oxidant and will kill biological agents in no time.

For your precious UV lenses, the ideal cure is just using them as they pass a lot of UV and that'll kill off the bad microguys.

[Andrea B.]

Yes! But the UV won't remove the existing fungus filaments. I still need to take it apart and soak the element in something. And wipe out the interior barrel.

[Bjørn Rørslett]

Either ammonia or hydrogen peroxide will do. Then, use the UV lenses for their intended purpose and they will have the work-out required to keep them fit for the future.

[Andrea B.]

Aha! Found us all a nice reference.

Disinfection, Sterilization and Preservation, 5th Edition, 2001
edited by Seymour Stanton Block
published by Lippincott Williams & Wilkins

See:  Page 1076, Figure 54.4 Microorganisms ranked according to their relative susceptibility to chemical disinfectants.

There are 5 susceptibility levels: highly susceptible, susceptible, resistant, highly resistant and extremely resistant.

Fortunately for us, fungal spores are listed as Susceptible to the following disinfectants: some alcohols, aldehydes, biguanides, ethylene oxide, halogens, peroxygen compounds, some phenols.

So for safety's sake, it looks like hydrogen peroxide and ethanol are the best bet for cleaning up lenses subject to the requirement that these chemicals not damage lens coatings.

[richardHaw]

Thanks Andrea! I forgot to add a warning! It is generally safe, we use it for cleaning chopping boards but it should be handled with care thats why i mentioned to use gloves. I will add a warning to that soon!!!

Bleach is also a good fungus buster

[Andrea B.]

Good ventilation always useful whenever using any chemical, yes? 

[richardHaw]

Yes, of course. Ammonia is strong but i have a high tolerance for that because i ate a lot of licorice tyrkist pibber or whatever the northern europeans call it 

Ammonia and hydrogen peroxide is what we used to cure my dog's skin problem. Its a potent mix so i also used it on my athletes foot. I got that from kicking the bag at training more than a decade ago. It comes and goes with medication but this mix killed it and now itsna thing of the past. This isnthe reason why i dont wrestle with the boys, you just dont know what you will get from training!

[Bjørn Rørslett]

"tyrkist pibber" = Turkish Pepper

[Akira]

Rick, this is a through write up!  Thanks for sharing.

If I remember correctly, the hydrogen peroxide was used to sanitize the wound.  It should be diluted H2O2, and sold under the name of Oxyfull or Oxydol.

Apparently Nikon uses hard coating also on the internal lens elements.  A well experienced Leica repairman once said that the soft coating is applied on the internal elements of Leica lenses, so cleaning them is very tricky.

[Erik Lund]

I hope I will never have to look at this thread again,,, 

[John Geerts]

A good written story, Richard. !  Very useful.