Treating fungus with UV stunning finding

[MalcolmL]

I recently bought an old lens which had the small traces of fungus in a middle lens element at the periphery. Thre fungus was minor but was completely around the element and in one place has encroached 1/3 of the way to the element's centre. Being fanatical I stuck the lens in a sunbed for 10 minutes to ensure death of the fungus.

What I now now see has stunned me.

The tiny fungal filaments noted before seemed to have 90% dissapeared (possible vapourised) as I can see only traces around 20% of the edge . It is so small now as to be 99.99% insignificant and is almost impossible to see.
It seems that the UV has somehow vapourised most of the hyphae. I have no idea if this has been seen before but it could be a non invasive way of treating mild fugus if it is a reproduceable effect.

May I postulate a mechanism ::

UV first kills fungus. Then the UV ionises the (organic) constituents in the hyphae and they react with other gases in the air and slowly (it has taken 10 days here) the elements vapourise without a trace.

Has anyone lesy come across this?

It could save a lot of legacy lenses from the tip if reproduceable !

Malcolm

[jito]

Did you left the lens out in the air for 10 days?

Sounds to me that the fungus was simply burned and turned into ashes. Ashes have very little structural integrity, couldn't they just be blown away by breezes? Effectively burning organic materials results into very little ashes, couldn't they have simply rolled down to the borders off the element?

Anyway, that's cool. I would repeat the procedure with the lens on different positions to make sure the fungus is all dead.

[MalcolmL]

Over the last 10 days I have used the lens - the pumping action of focusing would have provided enough aiflow. I have now checked and checked over and over to make sure I am not deluding myself and I am not.
I will repeat this again on another lens, do before and after macro pics and post the results here in due course.
Malcolm

[NikonD]

show us the UV light contraption

[Excalibur]

On TV recently there was a programme about decay, and that mold/fungii etc are very important for the world's recycle mechanism, anyway it was mentioned that there are 500 spores/cubic metre of air in the average home. Mind you I would have thought it would vary for the time of year.

[visualopsins]

[kds315*]

Good results, so please document that when you treat a 2nd lens, that would be great!
I'm happy for you that it worked that well!!

[Attila]

[Lloydy]

Stolen from Wikipedia -

Ultraviolet Radiation (UVR) from the sun and in tanning beds

The sun emits UVR in the form of A, B, and C waves. They are named according to the length of the wave and are associated with various health events. The ozone affects UVR from the sun and different amounts reach the earth's surface depending on the wavelength. Sunbeds can have the same health effects as UVR from the sun.[29]
UVA wavelengths (315-400 nm) are the longest wavelengths, and are only slightly affected by ozone levels. Most UVA radiation is able to reach Earth's surface and can contribute to skin aging, eye damage, and can suppress the immune system.[29]
Most of the UV radiation in tanning beds is UVA, but may be 10 to 15 times more intense than midday sun.[25]
UVA penetrates the skin more deeply and does not cause a burn
UVA does not damage DNA directly like UVB and UVC, but it can generate highly reactive chemical intermediates, such as hydroxyl and oxygen radicals, which in turn damage DNA.
The World Health Organization’s International Agency for Research on Cancer Working Group on artificial UV light and skin cancer positively associates the use of sunbeds with cutaneous malignant melanomas.[12]
UVB wavelengths (280-315 nm) are strongly affected by ozone levels. Decreases in stratospheric ozone mean that more UVB radiation can reach Earth's surface.[29]


UVB causes burns, snow blindness, immune system suppression, and a variety of skin problems including skin cancer and premature aging.[29]
Short-wavelength UVB has been recognized for some time as carcinogenic in experimental animals.[64]
UVC wavelengths (180-280 nm) have the shortest wavelengths, and are very strongly affected by ozone levels. Virtually all UVC radiation is absorbed by ozone, water vapor, oxygen and carbon dioxide before reaching Earth’s surface.[29]
Tanning lamps do not emit UVC

Would something like this wired up inside a storage cabinet be enough ?

http://www.maplin.co.uk/uvlight-source-4848

Or is the wattage / frequency different, and enough to make a cheap small UV lamp such as these worthless for what we might need ?

[MalcolmL]

The device was a simple tanning sunbed I hired in a gymnasium for 10 dollars - I gave it 10 minutes. Its equivalent to several hours intense sunshine without the heat .
After having decided to try a sunbed for this use I did a quick Google on the idea. Apparently a small flourescent tube UV like the Maplins device just does not have the power to fry the fungus. Suggest sinbed hire a good one. I have had an independent observer examine my lens andhe confirms that the fungus now occupies only about 10% of the circumference. Before treatment it was all the way round.
There is a lot of energy in these sunbeds but immediately after treatment there was no difference in the appearance of the hyphae. There is clearly a profound chemical change in the hyphae that allow it to dissintegrate after trteament and blow away as a fine dust. It could be an ozone / free radical effect.
If this is the case then if there was a heavy infestation the dust created after treatment may still leave a residue in the lens.
The total weight of the hyphae in my lens could only have been a fraction of a microgram - easy to oxidise with ozone and disperse without a trace.
I intend to do some reaseach and do a proper controlled, photographed experiment in due course.
Cheers


Malcolm

[Lloydy]

Interesting, and cheap if you hire the bed by the hour, or get someone to take your lens in with them.

Did the lens you tried have any etching on the glass ? I'd be very interested to see what the results were on a heavily infested lens, obviously it wouldn't 'correct' any etching, but if it removed the fungus so completely that the pitting was clean it might still save a lens ?

[bob955i]

[eddieitman]

I have used one of these http://www.ebay.co.uk/itm/36W-Tunnel-Style-UV-Lamp-Dryer-Gel-Nail-Curing-Art-/220807310010?pt=UK_Health_Beauty_Nails_Manicure_Pedicure_CA&hash=item3369242aba to successfully de-yellow a zeiss pancolar and also to kill fungus on a konica by removing the element and placing it under the UV.
mine cost me 99p on an auction and £3.50 postage

[MalcolmL]

Done some closer inspection of above mentioned lens. Thre fungus that was in the middle of the lens was 100% vapourised. The fungus still visible is behind the front elementand and is untouched by the process.
Comment
The UV would be at its greatest intensity in the middle / back of the lens where the light is more focused.
Link on ozone as an industrial cleaning agent ::

http://www.ozmoticsinsider.com/clean-in-place-cip-use-of-ozone-in-industrial-cleaning-applications/

AND:: quote""Advanced Oxidation

Advanced chemical oxidation processes make use of (chemical) oxidants to reduce COD/BOD levels, and to remove both organic and oxidisable inorganic components. The processes can completely oxidise organic materials to carbon dioxide and water, although it is often not necessary to operate the processes to this level of treatment

A wide variety of advanced oxidation processes are available:

chemical oxidation processes using hydrogen peroxide, ozone " (my bold) unquote at ::


http://www.lenntech.com/index.htm

Complete oxidation to water and CO2 sounds about right. Clearly need enough ozone to complete all reactions.

Need to find a way to get up the ozone levels behind the front element. ((The whole sunbed area stinks of ozozne)).
Malcolm

[youngcoby]

Hello Malcolm,

any news on a second attempt? I'm very curious about the results....

Filip

[tikkathree]

[Excalibur]

[ProfHankD]

I'm very curious as to what mechanism may have been at work in removing the fungus.

UVA is all that typical lens glass lets pass in any quantity, and UVA is believed to kill fungus (or at least render it dormant), but not remove it. It seems to be the UVA that fixes radioactively-yellowed lenses... and nobody else has reported disappearing fungus from such treatments.

UVC is the only one that can create ozone from air, but tanning beds are mostly UVA with a little UVB -- no UVC. Even if there was UVC output, it wouldn't make it through the glass in most lenses.

The comment that the tanning bed smelled of ozone leads me to think that ozone is the real answer. A tanning bed shouldn't generate ozone, but electrical arcing easily can, so I'm betting there was a defective contact somewhere causing this. Certainly, high ozone levels are known to have very dramatic sterilization effects, and could reduce fungus to basic components that would disintegrate over a short period.

In summary, I'm guessing that forced exposure to ozone might be the fungus-cleaning mechanism that wouldn't require opening the lens. I have an ozone-generating air cleaner... I'm thinking I might try sticking a fungus-infected lens in that environment for a week. After all, if the fungus could get in and get moisture, the area can't be that well sealed, and ozone should be able to get in. Now to find an fugus-infected lens.... Out of 100 lenses from eBay, I don't have one with an obvious infection (the only one I got that had it, I returned long ago).

Has anybody else ever tried an ozone exposure cleaning of fungus?

[my_photography]

Interesting finding on the UV thing. I wonder how long 10 minutes of sunbed is equivalent to under the hot sun? One thing I am worry is will hot sun bathing dry up the grease or will it harm the coating of the lens.

[LucisPictor]

It is a widely known fact that UV-light will harm fungus.
The problem is to get that UV-light to the fungus.
Glass as such stops most of the UV beams. (That's why you won't quickly get a sunburn when sitting inside a car.)
And coated glass is perhaps even more effective.

You have those UV-filters that you can screw into the filter ring. Those really prevent UV light from coming through.

But a high intensity UV light might get through to a certain extend. Hard to say.

I do have a UV-lamp in my cabinet. One of those that are used inside a reptilarium normally. Those are pretty strong and you have to be careful when handling them. Don't have them shine into your face/eyes directly for longer.

But my intention is not to kill possible fungus inside the lenses but rather cleanse the environment inside the cabinet from "free" fungus spawn. And then again, I have read that fungus spawn doesn't give a damn about UV light and that they coul survive on Mars!

But my lamp doesn't harm, so I use it every now and then...

[visualopsins]

[ProfHankD]

[Sevo]

[MalcolmL]

I now have a large jar that was seeded with a trace of butter (to emulate lens grease) and left in a dark cupboard for a month. There is a typical lens type fungal growth from one point spreading ot several cm. I am going to do a series of macro photographs before and after UV treatment to see in a very controlled way, how real and how much this UV effect is. I will publish the results here (and maybe officially as an original paper) once I have the results.
Malcolm

[MalcolmL]

My lovely Mycelium in my jar was exposed to sunbed UV 5 days ago and the visual appearnce has not changed at all. I cannot reproduce the results I had in my lens. (My lens I eventually sold free of fungus - I tried to show it to the purchaser but neither of us could see any).
Possible explanations:;
1) The conditions inside a lens are different from inside a jar so the physical environment oin the jar was less conducive to frying the fungus
2) THe fungal species were different and had different UV senitivities to destruction
3) We were visually mistaken on viewing the fungus in the lens and so drew erroneous conclusions.

Well that just about wraps that up for me.