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wager123
29-Sep-2010, 07:11
hi
i just returned from a several month trip and found that a couple of len's i have but haven't used in a while ( enlarger ) seem to have what looks like the start of a fungus growth. i have read tht putting them out in the sunlight will kill it if it's fungus. am i correct in assuming that it the UV light from the sun that does this and if so could i just put the len's under the light from my uv light box?
thanks
mitch

BrianShaw
29-Sep-2010, 07:19
Your light box may actually dispense more UV than the sun and may be a better option. I've read many accounts of people using UV lights for fungus killing.

GPS
29-Sep-2010, 09:48
It depends on the fungus type and where it is present. Inside fungus (in between the lens elements) or outside fungus (on the outer elements) are different. The outside fungus can be cleaned easily, the inside one demands more attention than just killing it.

Ole Tjugen
29-Sep-2010, 13:52
I admit to opening this thread only to find out what lem's fungus is. I have an interest in mycology, you see - but common lens fungus well know and isn't edible or very attractive. ;)

Steven Tribe
29-Sep-2010, 16:18
Lem in Danish is one of the many words for the male reproductive organ. As well as a town in Jutland.

D. Bryant
29-Sep-2010, 16:36
Lem in Danish is one of the many words for the male reproductive organ. As well as a town in Jutland.

What's the male non-reproductive organ called? Just curious. :)

BrianShaw
30-Sep-2010, 06:54
What's the male non-reproductive organ called? Just curious. :)

It's called "baseball bat".

Stephane
30-Sep-2010, 08:54
What's the male non-reproductive organ called? Just curious. :)

The Hand

Michael Cienfuegos
30-Sep-2010, 10:13
What's the male non-reproductive organ called? Just curious. :)


It's called "baseball bat".


The Hand

ROTFLMAO! :D :D :D

Lars Daniel
30-Sep-2010, 10:15
Lem in Danish is one of the many words for the male reproductive organ. As well as a town in Jutland.

I am glad I am not the only one who thought about stuff you donīt really want to. :rolleyes:

wager123
30-Sep-2010, 15:53
come on guys, give me a break !!! i was in a hurry and hit the wrong key.

Barry Kirsten
7-Oct-2010, 21:37
I found this link recently and it aroused my interest:
http://www.skgrimes.com/popsci/index.htm

I have never thought that I might attempt pulling a lens apart to remove fungus between elements, but having read this I think it's very do-able for someone prepared to approach it very carefully.

Good luck,

Baz.

Steven Tribe
8-Oct-2010, 02:35
Dear Barry,
I assume you have some "growth" between cemented lenses. The chances of this being a glass attacking fungus are very small. Canada Balsam deteriorates in a number of ways:

- Edge browning. Dehydration/oxidation of the balsam which is reached by air. This is often combined with a slightly yellowing of the complete area. It appears that the brown pigment created in the edge can diffuse into the Balsam layer which acts as a kind of liquid layer. When the old balsam is removed by solvents, there often remains a whitish crust where discoloration was worst. This can be removed using finger nail technique!

- Crystalline specks or "seaweed/fern growths". Specks often appear in Balsam without any apparent cause. They are stable. A different sort is more malignant. A crystalline area (often starting at the edge) grows gradually and can adopt very organic looking patterns. They grow in random directions - the adjoining balsam to the crystal area is "seeded" to precipitate the new deposit. It is often mistaken for fungus.

- Lenses which have reached the stage of complete separation become dreadful in appearance. Apart from the brown colour, the white deposit on the lens surface becomes very visable. These are the easiest lenses to clean though!

Barry Kirsten
9-Oct-2010, 16:51
Hi Steven,

Thankfully I haven't any lenses with defects at this time, but thank you very much for that helpful information. Having just returned to photography after several years off for study, I'm reacquainting myself with all that I used to love about photography.

I was very interested to find the link I mentioned about cleaning and re-cementing lenses, and was surprised to realise that it's quite within the scope of anyone careful and game enough to try it. With the extra knowledge you've provided I'd certainly give it ago if need be. Again, many thanks.

Barry.

jan labij
10-Oct-2010, 13:37
I am sorry to admit that I also wondered who lem was, and I was breathless with anticipation to find out about his fungus.