Fungus? Remedies? (Page 3): The mottling you see is underneath the edge paint of the front element. The only cure is to remove all the paint with a good solvent and repainting the...

rjriggins11 Loc: Colorado Springs, CO

The mottling you see is underneath the edge paint of the front element. The only cure is to remove all the paint with a good solvent and repainting the lens. Spider web fungus on the glass needs to be cleaned thoroughly with alcohol or acetone.

KlausK wrote:

This is a picture of an older manual focus Canon FD 28mm F/2.0 lens. The lens is in overall very nice shape - except for what has been developing inside of it.

What's your verdict? Garbage or worthwhile having it professionally cleaned?

Thanks!

rook2c4 Loc: Philadelphia, PA USA

GC-FineArt wrote:

The white dots, especially since they form very obvious concentric rings, is far more suggestive of some sort of (terminal :-( ) delamination problem with one of the internal elements rather fungus. Its true that the latter can appear as tiny white spots at times but the pattern is invariably random -- the little buggers simply dont organize themselves such a regular way.

Good point. I've seen lenses with fungus, but none looked quite like this - arranged in multiple circular beaded patterns. When I first looked at the photo, my first thought was that the lens had been submerged in a liquid substance, then rapidly spun/rolled until the circular patterns formed on the inner lens elements, which then dried out.

Screamin Scott Loc: Marshfield Wi, Baltimore Md, now Dallas Ga

Make sure you get yourself a set of JIS (Japanese Industrial Standard) screwdrivers. While it may look like the screws are Phillips, using a Phillips head screwdriver will cam out the the screws, making it a royal pain to remove (think tap & die)... Plus, if you do decide to attempt a cleaning, make sure you document every step & mark the lens so that you put it back together the same way, otherwise, the focusing will not be correct ...

MT Shooter wrote:

The lens is of minimal value. I would think it would be a good sacrificial lamb to your curiosity, disassemble it and try cleaning it yourself. Then see if you can put it back together properly. That's how I started repairing my own old lenses. Its fun, and rewarding when you get it back in shootable shape.

speters Loc: Grangeville/Idaho

KlausK wrote:

This is a picture of an older manual focus Canon FD 28mm F/2.0 lens. The lens is in overall very nice shape - except for what has been developing inside of it.

What's your verdict? Garbage or worthwhile having it professionally cleaned?

Thanks!

Looks like garbage to me, or since it may well be, you could just start taking the whole thing apart (can't damage anything, its garbage anyway) and try your best to get rid of it.

KlausK Loc: Brewster, NY

cranepix wrote:

Place it in damp/warm place for a month, and perhaps you might use what has been grown to cure diseases; and thus be awarded the next Nobel Prize.
Good luck !

That would be quite something. Even Fleming had to share his with two others ... :roll:

And thanks to everyone! I'll keep you posted.

johneccles Loc: Leyland UK

It would not work here in the UK, we have not see the sun for weeks/months.

KlausK Loc: Brewster, NY

I love London, but the weather is usually quite predictable ... :|

marcomarks Loc: Ft. Myers, FL

SteveR wrote:

I had a nice Sigma telephoto that developed fungus in the rear lens. I was told that it really couldn't be fixed, or wasn't worth fixing.

Me too. And nobody will buy it so in the trash it went.

wj cody Loc: springfield illinois

KlausK wrote:

This is a picture of an older manual focus Canon FD 28mm F/2.0 lens. The lens is in overall very nice shape - except for what has been developing inside of it.

What's your verdict? Garbage or worthwhile having it professionally cleaned?

Thanks!

what you are seeing is not fungus, but separation of the front lens element group due to the balsam cement drying. this happens often with older lenses. the folks at SK Grimes used to have a clean room and reset the elements, but they have discontinued the service.
however, from the angle of view of your photo, it appears if you stop down the lens one stop, you should find the lens will work just fine. also, it may never progress, but stay as is.
hope this is of assistance to you.

KlausK Loc: Brewster, NY

wj cody wrote:

what you are seeing is not fungus, but separation of the front lens element group due to the balsam cement drying. this happens often with older lenses. the folks at SK Grimes used to have a clean room and reset the elements, but they have discontinued the service.
however, from the angle of view of your photo, it appears if you stop down the lens one stop, you should find the lens will work just fine. also, it may never progress, but stay as is.
hope this is of assistance to you.

Thanks. I thought it was fungus, but it does look oddly symmetrical.

wj cody Loc: springfield illinois

KlausK wrote:

Thanks. I thought it was fungus, but it does look oddly symmetrical.

my pleasure. among large format photographers it is called "schneideritis", as lens elements from schneider kreuznach sometimes would separate and the little dots are just what you are seeing. i don't believe, from your image, that this should interfere with using your lens.
good luck with it.

KlausK Loc: Brewster, NY

I guess "Schneideritis" is rather hereditary than contagious, but in this case it mutated into Canoneritis ...

Thanks again!

nikon_jon Loc: Northeast Arkansas

dirtpusher wrote:

sunshine and heat kills mold...

Sunshine and heat may kill the mold, but will it eliminate the mold that is already there?

wj cody Loc: springfield illinois

nikon_jon wrote:

Sunshine and heat may kill the mold, but will it eliminate the mold that is already there?

if yu are speaking of a lens which has mold, then for this reply, i'm going to assume you mean fungus. fungus can appear as spider-shaped or snowflake form, usually. now cleaning is a subject unto itself. if it is between the lens elements, then you need to find a repair service with a clean room which specialises in separating elements and regluing them, once the cleaning is completed. on the outside surface of elements, some cleaning can be done. but...and here's the big one, if the fungus has eaten into the lens coating (and you can feel this by using a fingernail - gently! over the surface of the element) nothing can be done.

having blathered about all that, sunlight will do nothing for fungus. you may be fortunate in that it is not on the rear element and does not continue to spread over time. often the lens remains useable as it is.
hope this is of assistance.

Screamin Scott Loc: Marshfield Wi, Baltimore Md, now Dallas Ga

Sunlight will stop the spread of fungus, but won't remove any damage that's already been done... What happens with fungus is that the lens will lose contrast & sharpness, the more there is of it. Minor cases may not even appear to affect the lens (but it does, you just can't readily see it)

wj cody wrote:

if yu are speaking of a lens which has mold, then ... (show quote)