Fungus in a lens

Fungus is a living organism that can grow anywhere provided that it is in a humid environment. As Papua New Guinea is a tropical country close to the equator, we do have very humid conditions here especially as you go farther north. Port Moresby can be arid during certain months but lately, it has become a bit more humid.

Some years back, I bought a camera bag whose contents were a vintage camera and various other objects. It was a lot purchase and I did not really know what I was going to get. When I opened the bag, inside were a film SLR, 2 lenses, 1 flash and 3 filters. The camera had a faulty light meter but was otherwise fine. So was the flash a 1 lens. The other lens was not kept properly and as PNG is so humid, fungus grew inside the lens.

The lens is a zoom lens from Sigma which is widely known as a Japanese third party lens maker. It isn't a bad lens but the fungus has clouded the glass elements inside and whenever I use it, the resulting photographs are cloudy at best. To prevent this from happening, keep some silica gel in your camera bag or wherever you store your camera gear. Better yet, get a dehumidifier for your room if your budget allows. You can also get those dehumidifying canisters that collect moisture but you have to be careful with spilling the collected liquid.

Here are photos of my lens which is now an expensive paperweight. Repairing a lens like this would cost more than the value of the lens itself so I have shelved the idea of getting it repaired.

my one and only sigma zoom lens.

i prefer prime lenses so this lens is quite long for me.

to zoom, you extend the lenses barrel, a design that is vastly different from most lenses today where you just twist the barrel.

this lens also has a distance scale for zone focusing, a feature that most modern lenses do not have.

the rear element is dusty.

the front element has an even layer of fungus making it cloudy.

inside, the lens is fine.

against the light, you can really see the resultant haze that the fungus has produced.

here is a sample photo taken with the lens.

So remember, keep moisture and humidity away from your lenses or you'll end up with an expensive paperweight and cloudy photos.