"crystal clear" lenses and fungus

I don't know if it happens to people here who buy second hand lenses
but I recently had two cameras with the beginnings of fungus on the
lenses that were described as "crystal clear, unmarked optics free from
scratches or fungus etc." Maybe it is just me but I know how fungus
starts. You get a film of grease first that is transparent composed of
hundreds of tiny transparent round deposits. Some time later (could be
years) the blobs are fewer and bigger. Some time after that these blobs
send out filaments and etch the glass.

I just spent five hours working on a Sonnar 180mm f2.8 to get the start
of fungus off the rear of the front element (if I had known how it was
constructed before I started, I guess it would only have taken an
hour). It was very early stage fungus so it hadn't even affected the
coating.

I got a lovely Ikonta with an Zeiss-Opton Tessar lens and that had the
bigger blobs but I cleaned that up and the fungus left only a slight
coating of its own on the glass (it was uncoated anyway so it might
even help).

Have other people come across this grease film in lenses they have
bought? If so, do you think it is fungus or not?

wrote in message
oups.com...
Have other people come across this grease film in lenses they have
bought? If so, do you think it is fungus or not?

Only one in my lifetime - on a Nikon enlarging lens.
I just threw it away.

"Done" wrote in message
...

wrote in message
oups.com...
Have other people come across this grease film in lenses they have
bought? If so, do you think it is fungus or not?

Only one in my lifetime - on a Nikon enlarging lens.
I just threw it away.


Useful response. Not.


rafe b
www.terrapinphoto.com

"rafe b" wrote in message
...

Useful response. Not.

Okay. I threw at the ass who sold it to me. Better?

Yup on two yashica mats. The original owners didn't even know until I
informed them. I happened to put the shutters on B and held the lens
up to the light which showed the haze on one of the inner elements (4
element design on the Yashinon). Lucky me, they were kind enough to
take it back at their own cost, otherwise I would have cried foul. I
have a junk mat bought for spare parts that has a lovely spiderweb
etching on the same element. Takes a good clean photo at f32 if I
really wanted it to. :-)

I had one cleaned, which left scratch marks on the inner lens, but I
use it anyway with good results. Makes for some interesting effects
with a bright lightsource/flash. Probably not ideal for others who are
pickier about their glass than I am.

wrote:



Have other people come across this grease film in lenses they have
bought? If so, do you think it is fungus or not?

Fungus doesn't grow on uncoated lenses, there isn't anything for them to
feed on. The zeiss opton tessar *if it is marked that way) is normally a
coated lens.

--

Stacey

"Stacey" wrote:

Fungus doesn't grow on uncoated lenses,

WHAAAAT? Man, that's a reach. Geeze, Stacey, yer gonna catch it for that
one. I'll help you set up yer barricades, then I'm outta there.

You wanna post a real stretch, try this: The only lenses I've had fungus in
were Asian lenses.

Coatings are fungus delicacies?

(FWIW I'm not sure if the inner elements on the yashinon 80/3.5 are
coated, which is where I found the fungus on the three I went
through...)

ELSAN wrote:
"Stacey" wrote:

Fungus doesn't grow on uncoated lenses,

WHAAAAT? Man, that's a reach. Geeze, Stacey, yer gonna catch it for that
one. I'll help you set up yer barricades, then I'm outta there.

You wanna post a real stretch, try this: The only lenses I've had fungus in
were Asian lenses.

It certainly gave me a chuckle. I'm reading this on a Friday, which is
even better. It helps set me up for a good-humored weekend. The last
post I read here that was as good as that was the one where is said
that purely opening and closing jpegs degraded them.

Dave the Guy wrote:
Coatings are fungus delicacies?

There might be something very nourishing in them - to fungus, at least.
)

(FWIW I'm not sure if the inner elements on the yashinon 80/3.5 are
coated, which is where I found the fungus on the three I went
through...)

I am guessing that all the exposed surfaces are coated.