Bado Loc: Louisiana

After the last hurricane in Texas flooding my sons home. My 50-600 lens sat on a shelf with 3 feet of water below for two weeks.
Well fungus grew a city in that lens.
Sigma pitched a big story we want to help.
So I sent Lens in and they said oh man we will knock off 100$ on a new one.
Did not accept , the lens takes good images in spite of the fungus , weird but true.
I am just itching to get in that lens and clean it myself. Anybody know how to do this and what tools?
So far I can’t even get independent repair shops to do it. I just want someone with balls to do it and try to clean as much as they can. If it comes out bad it’s on me
Any ideas out there

Longshadow Loc: Audubon, PA, United States

The fungus can wind up etching the glass - permanent damage.

PixelStan77 Loc: Vermont/Chicago

Hope this helps.

https://www.youtube.com/watch?v=SqQZq176Bh0

jwreed50 Loc: Manassas, VA

I'm told by those who do it that the only way to eliminate the fungus in a lens is to disassemble the lens and literally bake the optical glass in an oven. I don't know what temperature they bake the glass at, but it's a high enough temperature that there is some risk of fracturing the glass -- probably as it cools. The person who did a couple of lenses for me had me sign a waiver before he would work on them.

Good luck.

Hanson

Yes it is true. If the fungus growth is not too profound, etching would take a while to happen or might not happen at all. So for now you are ok to shoot, probably let it exposed to sunlight intermittently.

Hanson

I don't think baking is a good idea, or an idea at all. Lens cleaning definitely can get rid of the fungus and that is all you need.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

I hope you have insurance . . .

bigboobphotos

If the lens still shoots, put in the sun to kill fungus and keep on shooting.

camerapapi Loc: Miami, Fl.

If the manufacturer clearly told you that a repair is not worth it that only tells me there is plenty of damage in the glass. Fungus eats the lens coatings and in many cases they are not easy to remove completely.
Believe me, you are going to be better off buying a new lens.

cameraf4 Loc: Delaware

Just a word of caution. Fungus in a lens can spread to your other lenses. Don't know how, but that's what I've always heard.

Canisdirus

I think you should have accepted Sig's offer.
Fungus is pernicious...and you had a colony.
It goes ...everywhere.

If you add up the time it would take to get doubtful results... you'd have paid for the lens with it.

Don, the 2nd son Loc: Crowded Florida

kymarto Loc: Portland OR and Milan Italy

This is the proverbial old wive's tale. The spores for fungus are everywhere and will grow if the conditions are right. Fungus will grow in any lens that is stored in the dark, at warm temperatures and at high humidity. Remove any one of those conditions and it will not grow, and any that exists will die, but it won't disappear. If you don't water a rosebush it will die but it will stay in the ground until you remove it. So if you can manage with the lens in the condition it's in and you store it in the right conditions, even with other lenses, it will not get worse and your other lenses are not in danger.

The problem with cleaning fungus in a complex zoom lens such as yours is that it needs to be completely disassembled to get to all the elements, which will cost more than the lens is worth. $100 off a new one is a kind offer. For an independent shop to do the work would also mean that they would probably need access to many small spare parts such as cams and bushings, and it would also mean a complete realignment of elements and precision optical bench testing. I don't blame them for not wanting that job.

CHG_CANON Loc: the Windy City

Beat me to it. Keep this fungus lens no where near any other equipment, not even inside the house, if possible.

Blair Shaw Jr Loc: Dunnellon,Florida

That was nice and so easy to do actually....surprisingly so. Thanks Stan.