I have just bought a TE 90 "as it" with what seems to be a developping fungus under the front lens (thin, scratch-like marks on the edge of the inside lens). Such problem is rather expensive to fix, I guess. Does anyone have any experience in that respect (e.g., approximative Leica rates, alternative methods (fridge?), etc.)? As the lens is still perfectly usable, I intend to use it as long as possible. Is there any risk of contamination of the body or of the other lenses? Does anyone have encountered such fungus contamination (lens/body/lens(es))? Thank you very much for your assitance,

Cordially,

Henry

-- Henry David (poulycroc@lycos.com), May 21, 2001

Answers

suggest you talk this over with john van stelten, of Focal Point, inc in louisville, CO 303-665-6640. where lens restoration issues are involved, i think he's the man.............

-- david kelly (dmkedit@aol.com), May 22, 2001.

Here's a suggestion: just leave the lens out in bright, hot sunshine for a few hours, this may well kill off the fungus by dehydratng/heating it. Of course it won't make what damage there is go away, but it's quite likely that the existing damage has no optical effects, as you say it's only around the edge of the element.

-- rob appleby (rob@robertappleby.com), May 22, 2001.

The front element of the T-E (fat or thin) is easy to remove, any competent camera repairman can do it and it will not require recollimation of the lens. If you're a do-it-yourselfer, some larger camera stores sell spanners or you can go to www.micro-tools.com . (You nave to be really careful not to let the spanner slip or the front element will have more than just fungus to worry about!) It is just a single element, not a cemented group. There is a thin black mylar shim just under the retaining ring, careful not to lose it. You may need to turn the lens over and tap until the element falls out, so make sure it has a soft place to land!Once it is out, it can be cleaned carefully. The underside doesn't have a "soft" coating, it's the same as the outer coating. I've heard many stories of what to clean lenses with, including ether (very flammable!) and lighter fluid (ditto!), but personally I've found that 50:50 vinegar and sudsy ammonia works just fine. You'll need to have a clean cotton cloth for cleaning and also to hold the glass with when you re-insert it so as not to put any fingerprints on it. You'll also want a can of compressed air or a strong blower brush to keep dust specks out when re-installing. Remember that the flat side goes in, the curved side faces out. If the cleaning doesn't do the trick, the glass may be permanently etched. A replacement front element should be available (probably a special-order) from Leica NJ. Make sure you have the serial# ready when you call. In addition to Van Stelten, DAG or Sherry Krauter also perform this kind of job superbly, if you're not into doing it yourself.

-- Jay (infinitydt@aol.com), May 22, 2001.

Fungus will have to be physically removed. It will not fade away in sunlight etc. Also I find that once it is polished off, the coating is never as good as before. Always keep your lenses in a dry box to avoid this. Same also with your camera body, filters, light meter. Anything that has optics in it.

Its incredible what that life form finds so tasty on a lens.

-- Yip (koklok@krdl.org.sg), May 31, 2001.

Fungus has been reported to spread. It is probably better to keep the lens away from other equipment. A "fungus" search will give many different approaches to this problem.

-- Niels H. S. Nielsen (nhsn@ruc.dk), July 05, 2001.

Errata: "Fungus" search on photo.net -sorry

-- Niels H. S. Nielsen (nhsn@ruc.dk), July 05, 2001.