Is Fungus Still Really a Problem?

Back in the day, fungus liked munching lens coatings about as much as it liked munching drywall.

Is it still the same today, or have lens coatings advanced beyond vulnerability to fungus?

Anyone have a recent case of fungus with a new model lens?

I think the issue with fungus is that it etches the glass, not the coating. But I don't know, maybe there could be coatings that afford some protection to the glass beneath. Etching is only a part of the problem... if you have significant fungus tendrils in your lens, you would still want it cleaned, and that would be expensive.

I spent almost 3 weeks in Ecuador in mostly humid conditions last month. I was worried about fungus, but there is no sign of that, phew. I guess it takes time for it to develop - and I got out before any fungus became visible.

Archibald wrote in post #18816376
I think the issue with fungus is that it etches the glass, not the coating. But I don't know, maybe there could be coatings that afford some protection to the glass beneath. Etching is only a part of the problem... if you have significant fungus tendrils in your lens, you would still want it cleaned, and that would be expensive.

I spent almost 3 weeks in Ecuador in mostly humid conditions last month. I was worried about fungus, but there is no sign of that, phew. I guess it takes time for it to develop - and I got out before any fungus became visible.

The fungus mycelium secretes hydrochloric acid that etches the glass as it reaches out for more food. But old-school lens coatings were themselves food for fungus.

Since we have rock-hard coatings these days that shed contaminates, I was wondering if they have come up with something that repels or resists fungus as well.

Fungus will grow if the conditions are right. Search around here on POTN and there are quite a few threads devoted to the subject as some members have fungus growing even with modern coatings. You can't get rid of the spores, they are already in all of your lenses, but you can make sure that it has no water (humidity) so it doesn't start growing. Store your lenses in a relatively dry place and you should be fine. If you live in a high humidity location, you might consider some method to control the humidity. A lens storage locker works great in high humidity location. Gel packs work ok if the lens is to be stored for an extended period in a tightly sealed container and you start with a freshly charged gel pack. Otherwise they are a waste of money.

RDKirk wrote in post #18816501
The fungus mycelium secretes hydrochloric acid that etches the glass as it reaches out for more food. But old-school lens coatings were themselves food for fungus.

Since we have rock-hard coatings these days that shed contaminates, I was wondering if they have come up with something that repels or resists fungus as well.

Hydrofluoric, not hydrochloric, according to the lore. Hydrochloric won't etch (most) glass. Hydrofluoric will. But it begs the question: does fungus contain fluoride, from which it produces HF? It seems weird.

gjl711 wrote in post #18816521
Fungus will grow if the conditions are right. Search around here on POTN and there are quite a few threads devoted to the subject as some members have fungus growing even with modern coatings. You can't get rid of the spores, they are already in all of your lenses, but you can make sure that it has no water (humidity) so it doesn't start growing. Store your lenses in a relatively dry place and you should be fine. If you live in a high humidity location, you might consider some method to control the humidity. A lens storage locker works great in high humidity location. Gel packs work ok if the lens is to be stored for an extended period in a tightly sealed container and you start with a freshly charged gel pack. Otherwise they are a waste of money.

Oh, I totally know how to handle humidity. I spent years in South East Asia back before commercial "dry boxes" were available--I built my own. I could write a book on it.

I was wondering if the most modern lens coatings have dealt with that particular problem yet, since they apparently shed water and other contaminates these days.

What do you call "modern"?

I've had fungus issues in Tamron and Sigma lenses built in the last 8 or so years (Tamron 28-75, Sigma 150 Macro). I've also cleaned fungus out of a friends Canon 17-85 many years back.

My Canon lenses have not had issues, however I should note that the 2 lenses I've personally had trouble with (mentioned above) are the ones that see the harshest conditions, being used in and out of airconditioned boats over the ocean (a nightmare for them fogging up and worst of all witnessing droplets forming inside the lens) and dragged through the bush along coastline in very humid weather.

First-hand information that fungus still attacks newer lenses is the answer to my question.

Not the answer I would have preferred, but there it s.

https://photography-on-the.net …read.php?t=1434​370&page=1

I have a Sigma 150-600C that has fungus in it now, so it is possible even with modern lenses to get fungus.

I've always been worried about this and for years now have kept a large silica gel pack in my bag. That being said I think you are suppose to warm them up in the over every so often to remove any moisture they have collected. I'm wondering if others have done this.

DSLR-Dude wrote in post #18826234
I've always been worried about this and for years now have kept a large silica gel pack in my bag. That being said I think you are suppose to warm them up in the over every so often to remove any moisture they have collected. I'm wondering if others have done this.

Silica gel really only works if it is fresh or regenerated in the oven and then protected from contact with air by keeping it in a sealed container. To keep camera gear dry, put the gear into a sealed container with the silica gel. Silica gel is a bit unhandy if you just have grains of it because it can spill or get into the gear. If it is in pouches, it is not easy to see if it still has drying power (many grades are indicating and do a color change when exhausted). I used to have a canister of it with a perforated metal top, but can't locate it any more. The Pelican product (link below) looks like it might be good. I have not tried it.
https://www.bhphotovid​eo.com …0_500_000_Silic​a_Gel.html

This should work, but note that some people say low humidity is not good for gear. They say that without properly explaining why. There is so much unverified info on the web. Anyway, it is at your risk.

DSLR-Dude wrote in post #18826234
I've always been worried about this and for years now have kept a large silica gel pack in my bag. That being said I think you are suppose to warm them up in the over every so often to remove any moisture they have collected. I'm wondering if others have done this.

first find out if you've got a problem. Get three cheap hygrometers from Amazon or a hardware store (in the thermometer department) and check the humidity in the area that you store your equipment. If you live in an airconditioned house or apartment, you probably have no problem.

Fungus is everywhere, but it needs 70% relative humidity for 24 hours to start growth. If you break that cycle, it does not grow. If you bring your equipment into an environment of less than 70% relative humidity for several hours a day, fungus won't be a problem.

Unless you store your equipment in a bag or case. You don't want to do that.

Was thinking. Would a storage box and a or couple 12v low wattage incandescent bulbs be enough to drop humidity levels down? Somebody mentioned that was in idea for DIY dry box.

Speedster159 wrote in post #19160913
Was thinking. Would a storage box and a or couple 12v low wattage incandescent bulbs be enough to drop humidity levels down? Somebody mentioned that was in idea for DIY dry box.

I mounted a low-wattage bulb in a kitchen cabinet when I was living in Okinawa and the Philippines back in the 80s. It worked well.