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Post by John Farrell on Jan 17, 2017 22:18:14 GMT -5
Fifteen years ago, I gave my daughter a camera. Last week, she returned it. It's a Yashica FX-7 I was given this camera in 2002; the leatherette was a mess - the outer layer had peeled off, and the camera frame was cracked, under the lens mount. I glued the frame with superglue, and recovered the camera with leatherette taken from a scrapped Yashica rangefinder camera. After reassembly, I took a series of shots of the weatherboard on my house, to check that the lens was properly aligned. When I gave my daughter the camera, there was a trace of fungus on the inside of the front lens element. This is part of an optical assembly which appears to be glued together, so cleaning was not possible. Last week, I saw that the fungus had spread: So - I've bought a UV torch, and I'm going to see if UV will kill the fungus:
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mickeyobe
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Post by mickeyobe on Jan 18, 2017 7:32:48 GMT -5
John,
I am looking forward seeing the results of this interesting and useful experiment.
Mickey
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Post by John Farrell on Jan 18, 2017 21:16:38 GMT -5
The torch has been shining in the lens for nearly 24 hours now, with little noticeable effect.
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Post by John Farrell on Jan 27, 2017 22:59:27 GMT -5
The torch has now been shining in the lens for 10 days...with short breaks for battery recharges. It's hard to know if its having an effect - so I'll just keep going.
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mickeyobe
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Post by mickeyobe on Jan 28, 2017 1:21:37 GMT -5
John,
I think it must be sunny in New Zealand at this time of the year. I wonder if sunlight would not provide appreciably more UV rays than a torch.
Mickey
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Post by John Farrell on Jan 28, 2017 3:04:30 GMT -5
John, I think it must be sunny in New Zealand at this time of the year. I wonder if sunlight would not provide appreciably more UV rays than a torch. Mickey We've had an awful summer so far, Mickey - and the lens would have to be left outside. Glass absorbs UV, and our windows are double glazed. Because the torch is shining through a glass element, I am losing part of the torch's UV output - the fungus is inside the lens. I think it has had some effect.
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Post by hannes on Jan 28, 2017 3:09:14 GMT -5
Does UV light only kill the fungus or should it disappear? I bought an Ikea Jansjö Led light. Right now it is over my foggy Miranda 25mm lens. Not long enough to tell if it works.
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Post by John Farrell on Feb 7, 2017 17:56:51 GMT -5
Well, the lens has now had the UV torch shining it it for a month. The result? The fungus is still there. Perhaps a different UV light would have some effect.
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Post by hannes on Feb 9, 2017 17:20:03 GMT -5
The fungus is still there. Perhaps a different UV light would have some effect. It looks like the fungus has allready damaged the coating. I have a Miranda 25mm lens which is/was hazy and has/had ight fungus. I put it under the Ikea Jansö LED light for at least 2 weeks. The haze seems to have disappeared and the image in the viewfinder ist contrasty again. I need to run a film through and compare against the other Miranda lenses. With the haze the look through view finder was very soft, also the images showed very low contrast and looked a little like "David Hamilton" image. Except that I do not have the models needed for such images :-) Hannes
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Post by raybar on Feb 9, 2017 22:51:34 GMT -5
Here's a brief article from CinemaTechnic in Hollywood California. cinematechnic.com/resources/avoiding_fungus_damageThey suggest direct sunlight (which contains lots of UV). As a last resort, you could try exposure to X-rays. Perhaps your dentist has a sense of humor.
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mickeyobe
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Post by mickeyobe on Feb 9, 2017 23:16:26 GMT -5
Here's a brief article from CinemaTechnic in Hollywood California. cinematechnic.com/resources/avoiding_fungus_damageThey suggest direct sunlight (which contains lots of UV). As a last resort, you could try exposure to X-rays. Perhaps your dentist has a sense of humor. As a last resort how about chlorine bleach. It worked without fail for forty + years on my bathroom tiles. Mickey
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mickeyobe
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Post by mickeyobe on Feb 21, 2017 11:40:20 GMT -5
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Post by John Farrell on Feb 21, 2017 13:29:11 GMT -5
Unfortunately, Mickey, I can't separate the lens elements to do this. They are glued into a plastic block. One suggestion I read to remove fungus was to use Ponds Cold Creme. I normally use methylated spirits, fuelite, and window cleaner.
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