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on Jul 8, 2016 15:21:04 GMT
Last Edit: Jul 8, 2016 15:22:26 GMT by biginovero
I was lucky to acquire and fx3 with a couple lenses for a pittance, camera, 50 1.9 and tamron 70-210 (19a) were clean, but the 35-105 was a fungi breeding farm.
Alas the front element apepars infected and for what I see it is a cemented doublet.
I soaked the main lens part and the detached front element in peroxyde/ammonia solution for more than one day, but the front lens seems to have lost only a minimal amount of fungi, even if the solution has clearly penetrated leaving an halo inside that will dry eventually away.
Having no collimating tools and being unwilling to spend some forty dollars for modern lens cement I think I will try more with soaking, however I was asking myself if tehre are other solutions available to get rid of the fungi without separating the doublet.
Lens has a good fame but it is worth not much more than a can of optical cement, and I doubt that collimating by eye would result in anything good.
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Status: Long, long time Contax and Yashica user; glad to be here and hope to contribute.
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on Jul 9, 2016 0:49:26 GMT
Last Edit: Jul 9, 2016 0:50:13 GMT by biggles3
I think you have a problem. Although it is relatively easy to neutralise fungi, removing them will require direct contact with the infected elements. My only thought about a way of clearing fungus without physically rubbing it off the glass once neutralised would be to destroy the infection with UV light and then use ultra-high frequency vibration to dislodge the dead spores and tendrils, though that would still require a hole/gap for the detritus to fall through to remove it completely from the lens. That does not really help if you wish to avoid separating the cemented glass...
From what you have said, I think you may have a lost cause in any case as, if the fungus has been resistant to 24 hours of soaking in your solution, I suspect it has already been etched into the glass; I fear that lens is now a paperweight.
One final thought - if all the items had been stored together, you may have future problems with cross-contamination so keep an eye on the other items.
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on Jul 9, 2016 23:53:09 GMT
Posted: Jul 9, 2016 23:53:09 GMT
I think you have a problem. Although it is relatively easy to neutralise fungi, removing them will require direct contact with the infected elements. My only thought about a way of clearing fungus without physically rubbing it off the glass once neutralised would be to destroy the infection with UV light and then use ultra-high frequency vibration to dislodge the dead spores and tendrils, though that would still require a hole/gap for the detritus to fall through to remove it completely from the lens. That does not really help if you wish to avoid separating the cemented glass... From what you have said, I think you may have a lost cause in any case as, if the fungus has been resistant to 24 hours of soaking in your solution, I suspect it has already been etched into the glass; I fear that lens is now a paperweight. One final thought - if all the items had been stored together, you may have future problems with cross-contamination so keep an eye on the other items. Well I suspect the infected one to have been stored in a different place since the tele zoom and the camera look pretty nice. The tele has very clean lenses with no traces of old cleaning, it looks unused. Only the camera has some rust on the metal part of the strap. Are you sure cross contamination to be a true problem? Some internet source maintain that spores exist everywhere, simply they are activated by the right humid environment. other people believe in cross contamination. I have already stored my tele zoom with my zeiss but in a dry environment. In any case I will clean it with isopropyl, even if appearance is that of a well kept item. I have no competence to study scientifically the fungus problem, a friend of mine is a seasoned professional chemist, maybe he will be helpful. The old 35-105 will become a source for parts, whatever be salvageable. I'm trying to adapt a prakticar 28-80 to the yashica mount, maybe the 35-105 bayonet ring could become the donor. |
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on Jul 10, 2016 0:04:41 GMT
Posted: Jul 10, 2016 0:04:41 GMT
btw, I have found chlorine bleach liquids in my favourite hardware store, I was thinking of exposing all my lenses to such vapors starting with some cheap examples.
Also I have read of borax and vinegar as mold/fungi killer solution, but my primary goal would be just to find vapors that are deadly for fungi and safe for lens coatings.
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on Jul 10, 2016 17:52:14 GMT
Posted: Jul 10, 2016 17:52:14 GMT
Before you start using really nasty chemicals the best way of cleaning fungus from lenses is good old fashioned Sensodyne toothpaste. I have no idea why, but this was taught to me in my very early days of repair and it has served me well since. Lightly apply, rub gently and then wipe off and polish.
If you separate the lens elements you are going to have a bit of an issue getting them back together because the adhesive and element are usually bonded in a vacuum to ensure the correct refractive index and provide the correct collimation.
I cannot state enough on here that chlorine bleach is NOT a good way forward due to the dangers of fume inhalation and experimenting with vapours just seems downright bonkers.
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on Jul 11, 2016 18:15:55 GMT
Posted: Jul 11, 2016 18:15:55 GMT
Before you start using really nasty chemicals the best way of cleaning fungus from lenses is good old fashioned Sensodyne toothpaste. I have no idea why, but this was taught to me in my very early days of repair and it has served me well since. Lightly apply, rub gently and then wipe off and polish. If you separate the lens elements you are going to have a bit of an issue getting them back together because the adhesive and element are usually bonded in a vacuum to ensure the correct refractive index and provide the correct collimation. I cannot state enough on here that chlorine bleach is NOT a good way forward due to the dangers of fume inhalation and experimenting with vapours just seems downright bonkers. I'm just at an experimentig stage, with many doubts. I used a breathing mask and kept myself in a ventilated place when dipping the lens in the solution,also I had gloves when manipulating it. I will likely use this lens as a donor, as you said repair of a cemented lens must be made in an apppropriate envoironment with specialized tools/machinery. Since this is just an hobby I won't waste money on stuff for which I could not even get the needed training. Sensodyne paste is available here as well, nice suggestion. I only feel badly thinking of dumping the lens in some obscure place in my (dry) cellar. As for fungus, I have found this interesting text dating back to ww2, with some real scientific research about fungus prevention in tropical climates. I assume the material they found wasn't tested on coated lenses so I do not know wether today it might make a good choice for cleanig/preventing fungus. www.europa.com/~telscope/fungus.txt156 |
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on Jul 13, 2016 9:06:04 GMT
Posted: Jul 13, 2016 9:06:04 GMT
I'm just at an experimentig stage, with many doubts. I used a breathing mask and kept myself in a ventilated place when dipping the lens in the solution,also I had gloves when manipulating it.
As I mentioned previously, if you need to use a breathing mask and have many doubts you SHOULD NOT be using this method. I have been repairing cameras and lenses for over 25 years and there is NOTHING that I can think of that is a safe way to clean lenses of fungus except the toothpaste method. If it needs more than that then the lens is either beyond repair or needs specialist and I mean highly specialist help.
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