Inspect mould removable?

[johnyu]

When inspecting a 2nd hand lens, I'm wondering if we can tell whether a lens has been cleaned to remove mould.

Thanks

[litefoot]

Originally Posted by johnyu When inspecting a 2nd hand lens, I'm wondering if we can tell whether a lens has been cleaned to remove mould. Thanks

Its hard to tell. One of the ways is to check the screws. Lens opened up by inexperienced hands may show signs of wear. Different screw heads is also another sign as screws are small and easily misplaced, they may not have the exact screw.

[johnyu]

Originally Posted by litefoot Its hard to tell. One of the ways is to check the screws. Lens opened up by inexperienced hands may show signs of wear. Different screw heads is also another sign as screws are small and easily misplaced, they may not have the exact screw.

Hi Litefoot,

Check for screws, that's a good point!

[yanyewkay]

good point but not exactly fool proof.

my belief is that if the mould has been cleared and the optics are clean. keeping it properly in a dry box should it keep mould free.

[jbma]

If the mould has been cleaned I see no problem then.

[yanyewkay]

the prob is that the mould will surely manifest itself onto the micropores of the glass surface (something like that) and will grow again once the coniditions are right. So keeping it in the dry box should be good practice.

[litefoot]

Originally Posted by yanyewkay the prob is that the mould will surely manifest itself onto the micropores of the glass surface (something like that) and will grow again once the coniditions are right. So keeping it in the dry box should be good practice.

Pores are all over the air. I am sure even an unopened lens are subjected to the risk of fungus infection in humid atmosphere. Only way to prevent it is to use it often and keep your equipment in Dry Box for long storage.

[Artosoft]

Hi,

Is it true that Tamron lens is more resistant to mould/fungus than Sigma lens? I hear this from the camera shop seller. It could be his trick to push me buy Tamron over Sigma (because he is out of stock of Sigma lens, the model that I am interested).

Anyone know something to share?

Thanks!
Arto

[yanyewkay]

Originally Posted by litefoot Pores are all over the air. I am sure even an unopened lens are subjected to the risk of fungus infection in humid atmosphere. Only way to prevent it is to use it often and keep your equipment in Dry Box for long storage.

yups quite true about the pores in the air part but the myth that using it everyday will not get fungus is not true. I think there was a post in CS quite some time back about this journalist that uses his equipment everyday but had a good harvest of mould in his lenses as well.. The mould may not grow on the surface of the lenses that are used everyday but the inside is a nice place to settle on.

[billpepsi]

Originally Posted by Artosoft Hi, Is it true that Tamron lens is more resistant to mould/fungus than Sigma lens? I hear this from the camera shop seller. It could be his trick to push me buy Tamron over Sigma (because he is out of stock of Sigma lens, the model that I am interested). Anyone know something to share? Thanks! Arto

Not sure about Tamron more mould resistant than Sigma, but a number of posting pointed out that Sigma lenses fogged up after 2-3 yrs, here is one of them.

http://forums.clubsnap.org/showpost....7&postcount=15

[yanyewkay]

from your link. .it seems that they fogged up from other reasons and not fungus. is that right? actually I have a tokina lens with me with looks a little fogged up (not fungus) but the pic quality is still very sharp.

[johnyu]

Originally Posted by jbma If the mould has been cleaned I see no problem then.

No, as far as I know, that's not the case. The reason why mould grows on glass but not anywhere else is mould LOVES and feeds on the delicious lens coating. The coating will be literally eaten away by the mould. So, the damage is irreversible.

[Artosoft]

So far I understand that people who keep their lens in dry box (or other box) with bulb light (to make the dry box (or other box) dry will tend to get fog instead of fungus on the lens.

Arto.