Fungus the bogeyman.

[Ralph Turner]

Something that lurks at the back of my mind…. no, not the fungus you understand, just worry of it lol. Anyway, as far as I’m aware the following points regarding fungus apply:
1) it requires a certain level of moisture to germinate and grow.
2) it requires a certain amount of nutrients in the form of dust, grease, organic particles etc to feed.
3) dark, still places encourage growth

4) UV-C light can destroy any hyphae (so long as it’s in direct line-of-sight of the light source), though less effective on dormant spores.
5) sodium peroxide kills it.
6) storing affected kit in dry, ventilated places away from dark, damp backs of cupboards in still air.
7) keep affected kit away from unaffected kit to minimise risk of contamination

8) there are thousands (millions?) of spores in seasonally varying amounts around us all the time (so potentially limiting the effectiveness of points 4 to 7 above)

Despite point no.8, though, I still probably worry about points 1 to 3 more than I should and tend to apply point no.8 possibly more than I need to.

If anyone has any thoughts on this, or any links to any definitive information, it would be much appreciated, t.i.a

 

[Stevenson Gawen]

It lurks in my mind a little too... I've never had a problem except in one (budget but decent ) Sony lens from 2015ish that seems to have a kind of mottling in it... don't know if it is fungus though.

I've never taken any precautions except not putting gear away wet (obviously I guess!).

But the fact that I live in Australia, in a part with relatively low humidity would help, even though our house is pretty old and not exactly watertight in some spots.

 

[Ralph Turner]

It lurks in my mind a little too... I've never had a problem except in one (budget but decent ) Sony lens from 2015ish that seems to have a kind of mottling in it... don't know if it is fungus though.

I've never taken any precautions except not putting gear away wet (obviously I guess!).

But the fact that I live in Australia, in a part with relatively low humidity would help, even though our house is pretty old and not exactly watertight in some spots.

As you say, keeping kit dry when not in use is probably the best course of action. Keeping one (or preferably both) of the key elements for growth away (food source/moisture) should help keep the dreaded lurgy in check. Although our part of Scotland (the south west) tends to catch the damper weather our house is, fortunately, pretty dry on the whole (particularly in view of the fact it’s an old stone cottage with solid walls). I do make use of re-usable silicone gel packs in my display cabinet as a precaution. So far, so good.
Um, I’ve noticed (particularly recently) how much I’m tending to use brackets in my ramblings (is that a good thing, or bad?)

 

[Stevenson Gawen]

re-usable silicone gel packs

I should probably get some of those...

use brackets in my ramblings

Ha! I seem to do that too now you mention it. I think it stems from an economical desire to fit as much information as possible into one sentence.

 

[Ralph Turner]

Ha! I seem to do that too now you mention it. I think it stems from an economical desire to fit as much information as possible into one sentence.

Lol. My missus would probably agree. Often when I’m talking to her about something (usually of a photograpic nature) I can see her eyes glaze over, so my sentence usually ends with the words blah-blah-blah so she knows when I’m finished

 

[Bill Watts]

Having spent a lot of my life travelling the world, and ending up spending 10 years in Singapore where humidity was an ever present issue, particularly at the elevated temperatures encountered there. The answer is dry cabinets. These were available many years ago at the Singapore airport shops even, and could be purchased and sent as unaccompanied baggage relatively cheaply to any destination (1980's to about 2000) however, with the coming of digital cameras and mobile phones the market disappeared and they are now only available in specialist shops in Singapore, I have not seen them for sale anywhere else I have been.

They work utilising a Peltier effect device which is fitted inside the sealed cabinet, cooling the air, forcing the water to condense out onto a sponge which passes through the cabinet to the outside, where the water evaporates, a humidstat controls the level of dehumidification in the cabinet. I have 3 x 60 litre units, and of all my kit (there is quite a lot) only 1 lens has a trace of fungus which was caused many years before my move to Singapore and purchase of the cabinets.

I now live in Germany, but the gear is still kept in the cabinets except when in use.

 

[Pete Askew]

I think you have identified the key element here. Moisture. Without it the spores will not germinate and growth will not occur. Having stated that, there are some species / strains that can grow at a lower moisture contents than others, albeit slowly. The consequences of the growth vary and on older lenses it can often be cleaned away with alcohol with little consequence. However, heavy growth can etch the glass and on more modern optics the coatings can be degraded.

As some of you know, my 'real' profession is a materials microbiologist and in many situations it is the control of moisture that is the critical factor when preventing microbial biodeterioration of materials.