Paul Edwards Posted February 6, 2010 Share #1 Posted February 6, 2010 Advertisement (gone after registration) I have just received an old 90mm f4 Elmar that I won on an auction site. I took the chance and got the lens at a very reasonable price. Cosmetically it is fine and optically is seems satisfactory for my purposes. However at the very edges of the front element I can see what I can only assume is fungus. This does not affect the image at all so in general I am happy with this lens. My question is if it is fungus is it contagious? Will it contaminate my other equipment ? and is there a way of stopping it from spreading further into the front element of the lens? Thank you. Link to post Share on other sites More sharing options...
Advertisement Posted February 6, 2010 Posted February 6, 2010 Hi Paul Edwards, Take a look here Lens Fungus. I'm sure you'll find what you were looking for!
christoph_d Posted February 6, 2010 Share #2 Posted February 6, 2010 Paul, Fungus is known to be contageous. Personally, if I had such a lens I would keep it far away from my "clean" equipment. In the past there seem to have been some places that would clean lenses like this, but at present I couldn't give you any address. Kind regards, Christoph Link to post Share on other sites More sharing options...
richam Posted February 6, 2010 Share #3 Posted February 6, 2010 It's contagious and can be ruinous. What you see as fungus damage is etching in the glass from fungus waste. The lens is probably not economically repairable. But if it's producing images ok for you, a dry heat treatment may help and provide you some security. Set it to wide open, on end, on a black object such as a velvet cloth or lens pouch. Then set a 40w or so incandescent lamp close to the top, looking straight into it. If you leave it for 24 hours, the fungus should be destroyed or at least neutralized, but the etching will remain. A few years ago, I visited the Leica repair facility in Solms and asked them about a fungus infected lens I had brought. When they saw it, a burly bouncer appeared and hustled me bodily out the front door with instruction never to bring the lens there again. That's an indication of how fungus can contaminate, so I recommend caution about using the lens or storing it near any other lenses you may have. Link to post Share on other sites More sharing options...
Paul Edwards Posted February 6, 2010 Author Share #4 Posted February 6, 2010 Hi thanks for your prompt responses I have now looked close at the lens in better light and the marks are actually on the barrel of the lens below the front element. Between the glass and the aperture blades. They are in a random pattern around the barrel each one looks similar to a snow flake , Could it just be some corrosion of the aluminum that the lens is constructed of.? There is no sign of any dust,dirt or oil inside the lens and it gives pretty good images . Link to post Share on other sites More sharing options...
hankski Posted February 6, 2010 Share #5 Posted February 6, 2010 It's contagious and can be ruinous. What you see as fungus damage is etching in the glass from fungus waste. The lens is probably not economically repairable...I recommend caution about using the lens or storing it near any other lenses you may have. On the same thread... what conditions cause lenses to contract fungus? I am thinking of the spotting scope that I keep stored in the trunk of my car. Regards, >Hank Link to post Share on other sites More sharing options...
SJP Posted February 6, 2010 Share #6 Posted February 6, 2010 and the marks are actually on the barrel of the lens below the front element.then it is not fungus, fungus refers to things growing in between the lens elements i.e. you can see them 'on' the glass/optical part of the lens. What you describe could be minor corrosion or similar and should not be of any importance. If the exterior is clean otherwise (no dings & dents) and the glass is clean then relax and be happy. If I read correctly you are referring to stuff on the barrel i.e. on the outside of the lens, or did you mean the inside of the barrel? Link to post Share on other sites More sharing options...
Paul Edwards Posted February 6, 2010 Author Share #7 Posted February 6, 2010 Advertisement (gone after registration) Yes the stuff is on the inside of the barrel but optically the lens seems good. Link to post Share on other sites More sharing options...
richam Posted February 7, 2010 Share #8 Posted February 7, 2010 On the same thread... what conditions cause lenses to contract fungus? I am thinking of the spotting scope that I keep stored in the trunk of my car.Regards, >Hank Hank, I'm not an expert but understand it's the presence of nearby fungus plus dampness. Link to post Share on other sites More sharing options...
richam Posted February 7, 2010 Share #9 Posted February 7, 2010 Yes the stuff is on the inside of the barrel but optically the lens seems good. Looks like you got a bargain after all. Link to post Share on other sites More sharing options...
dkCambridgeshire Posted February 17, 2010 Share #10 Posted February 17, 2010 There are so many myths concerning fungus in lenses. A lens interior contaminated with fungus is highly unlikely to contaminate or cross infect another lens. The fungal spores which caused the growth are probably already present in the atmosphere/air in their millions just waiting for the right conditions to spawn. They may even already be on the glass but are so small they are not visible. If the interior of the lens is damp for any reason eg lens taken from cold atmosphere into a warm atmosphere causing condensation then that may trigger the spores to spawn and they seem to like glass. Similar conditions cause fungal growths in bathrooms. If there is fungus inside a lens it is not going to contaminate a nearby lens because it is highly unlikely that any spores will be able travel outside the lens. I was talking to a well known independent Leica technician last year who routinely cleans Leica lenses affected by fungus. Lenses he receives from the far east eg Singapore are often worst affected because they have been stored in a more humid climate. Provided the fungus has not etched into the coating and glass it can be remedied merely by wiping it away and treating the glass with isopropyl alcohol. If the lens element has become damaged then it can be professionally repolished and recoated and this is done routinely every day by specialist optical technicians eg OIB in Balham Optical Instruments (Balham) Ltd. - Manufacturing, Servicing and Repair of all types of Optical Instruments. If you are worried about fungus please read what Thomas Tomosy has written on the subject in his camera/lens repair manuals - he wipes off the fungus after dismantling the lens and advocates halting the spread of existing fungus inside a lens by exposing it to sunlight. A lens need not be written off because it has signs of fungus and with a simple prime lens eg an Elmar it would not cost much to have it dismantled and cleaned if you know where to have it treated. I recently had a 50mm Summicron lens cleaned including polishing and recoating two lens' elements and the cost was just over £100 which was very cost effective. Optical repair agencies do not refuse to accept fungused lenses as they know that cross contamination is not going to happen. And please do not think that every smudge or smear or mark inside a lens is fungus ... it could be dust or a flake of paint or balsam separation. Sometimes a lens might only be affected by fungus behind the the front or rear element and if so it could be a simple DIY job to unscrew the element and clean it yourself but I would not advocate trying this unless you feel confident and have the right tools to unfasten the retaining ring(s). Tomosy's books include articles/illustrations on Leica lens dismantling ie the older more simple Elmar and Hektor lenses ... not the more complex modern designs. dunk Link to post Share on other sites More sharing options...
earleygallery Posted February 17, 2010 Share #11 Posted February 17, 2010 Excellent post Dunk! The mods should make that a sticky. Link to post Share on other sites More sharing options...
dkCambridgeshire Posted February 17, 2010 Share #12 Posted February 17, 2010 Expect you must have seen a few fungused lenses remedied James when you worked in the trade? Cheers dunk Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 17, 2010 Share #13 Posted February 17, 2010 Paul, it sounds like a CLA is in order for the lens. It will probably help the IQ even if you don't have fungus in there. I have had a 50DR and a 90 'cron (Canada) CLA'd and the images improved significantly. These CLA's cost less than $100 per lens. the improvement in IQ is worth more than that. Link to post Share on other sites More sharing options...
dkCambridgeshire Posted February 17, 2010 Share #14 Posted February 17, 2010 This is a 1960 50/2 Summicron recently cleaned, lens elements polished and recoated ... and total cost of lens purchase including the CLA and recoating etc was less than £200 ... the front and rear lens elements were very noticeably scratched when first purchased. There was no fungus but the pix illustrate what can be achieved with damaged coatings. The 'spots' are reflections. And the technician also sourced a replacement infinity button which was missing when lens was first purchased. Cheers dunk Link to post Share on other sites More sharing options...
richam Posted February 18, 2010 Share #15 Posted February 18, 2010 dunk, many thanks for the information and lead. I've emailed Optical Instruments about restoring some of my lenses, and am hoping for the best. Link to post Share on other sites More sharing options...
dkCambridgeshire Posted February 18, 2010 Share #16 Posted February 18, 2010 dunk, many thanks for the information and lead. I've emailed Optical Instruments about restoring some of my lenses, and am hoping for the best. They are usually quite busy ... mine took almost 3 months to be completed. Cheers dunk Link to post Share on other sites More sharing options...
wilfredo Posted April 22, 2010 Share #17 Posted April 22, 2010 Paul, it sounds like a CLA is in order for the lens. It will probably help the IQ even if you don't have fungus in there. I have had a 50DR and a 90 'cron (Canada) CLA'd and the images improved significantly. These CLA's cost less than $100 per lens. the improvement in IQ is worth more than that. Where in the U.S. is this service available? Link to post Share on other sites More sharing options...
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