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03-28-2016, 02:36 PM   #31
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yup fungus, clean it

03-29-2016, 05:43 PM   #32
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QuoteOriginally posted by niceshot Quote
yup fungus, clean it
Totally agree, its fungus and really should be cleaned. Find some guides and have a go. If it all goes horribly wrong (which it probably won't) it's only $30.
If you manage to do the job you end up with a pristine lens that only cost $30 and you will have learned how to do it.

The first one I did was the Pentax A50 1.7. It took me ages doing it step by step through guides I found here, some of the steps I realised afterwards I didn't have to do. I Managed to lose the little ball bearing and spring that makes the aperture go click. I just jammed the automatic contact into the lens mount and now its permanently set on A and the aperture ring does nothing. But its ended up one of my favourite lenses, and it cost next to nothing

I have cleaned many since then. So have a go - you have nothing to lose
03-29-2016, 07:27 PM   #33
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well alternatively they can send it out to a qualified technician . Or take the risk and try it themselves. I have found that most of the time haze is caused by condensed oil on the lens elements coming from the aperture blades.
03-30-2016, 03:39 AM   #34
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My photo above shows that the problem is fungus, rather than condensed oil. The threads are typical of fungus from what I've read in these Forums. I still hesitate to try and disassemble the lens since it's not very likely that I will do a perfect job. As Jatrax says, the fungus is already dead and the remaining spores will only reinfect the lens if moisture is allowed to re-inter the lens interior. I've carried out a few quick tests with the lens and it is a joy to use and works perfectly. I wouldn't want to jeopardize this by losing screws or misaligning the elements, etc. Better to use it, as is, and keep it dry to stop the fungus from growing. If it was a less desirable lens than the 200 mm f/5.6, I would probably have a go, as two of you suggest.

03-30-2016, 04:15 AM   #35
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It is fungus. Luckily it is a simple lens and it is likely not difficult to clean. I have never serviced this lens but to me it seems that there is a single rear optical block that unscrews and two lens groups in the front that can be accessed for unscrewing by removing the name ring.

If the fungus is in front of the diaphragm, it will probably not be visible on pictures. If it is behind it, it will probably be visible in specific conditions. If it was my lens, I would have cleaned it, but I really do not advise you to do it if you do not have special tools for the job and that means quality screwdrivers and a lens spanner as a minimum.

So, if the fungus does not show on pictures, you are ok and do not touch it if you are not comfortable with tinkering of this kind. Anyway, the damn thing is probably dead for years or decades and spores you can not really eliminate, they are literally everywhere, even in every breath we take.

To check if your fungus is visible, just take a picture at a minimal focus distance wide open with a shiny stuff in the blurry background. Dew on vegetation, sunrise/sunset through a foliated tree will work. Street lights during the night will also do it but you will need a tripod or any kind of object you can put your camera on (use 2 or 10s delay).

Even if you see it then, it will probably not show in normal photography.

It is a good lens, have fun.

Last edited by Audi 5 cyl; 03-30-2016 at 04:23 AM.
03-30-2016, 07:08 AM   #36
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QuoteOriginally posted by Audi 5 cyl Quote
It is fungus. Luckily it is a simple lens and it is likely not difficult to clean. I have never serviced this lens but to me it seems that there is a single rear optical block that unscrews and two lens groups in the front that can be accessed for unscrewing by removing the name ring.

If the fungus is in front of the diaphragm, it will probably not be visible on pictures. If it is behind it, it will probably be visible in specific conditions. If it was my lens, I would have cleaned it, but I really do not advise you to do it if you do not have special tools for the job and that means quality screwdrivers and a lens spanner as a minimum.

So, if the fungus does not show on pictures, you are ok and do not touch it if you are not comfortable with tinkering of this kind. Anyway, the damn thing is probably dead for years or decades and spores you can not really eliminate, they are literally everywhere, even in every breath we take.

To check if your fungus is visible, just take a picture at a minimal focus distance wide open with a shiny stuff in the blurry background. Dew on vegetation, sunrise/sunset through a foliated tree will work. Street lights during the night will also do it but you will need a tripod or any kind of object you can put your camera on (use 2 or 10s delay).

Even if you see it then, it will probably not show in normal photography.

It is a good lens, have fun.
Howdy Audi. Thanks for your good advice. I'll check out the lens, as you recommend, and see if the fungus becomes visible under adverse conditions. As you say, fungus is everywhere - on our clothes and gadget bags but we only get hysterical when we see it on a lens surface. I don't take it lightly but I never let it become a major concern. I don't live in a jungle, or take outside photos in a hurricane, so I can keep my equipment dry. This should help me control any fungal spores. Thanks again.
03-30-2016, 12:02 PM   #37
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QuoteOriginally posted by psoo Quote
My photo above shows that the problem is fungus, rather than condensed oil. The threads are typical of fungus from what I've read in these Forums. I still hesitate to try and disassemble the lens since it's not very likely that I will do a perfect job. As Jatrax says, the fungus is already dead and the remaining spores will only reinfect the lens if moisture is allowed to re-inter the lens interior. I've carried out a few quick tests with the lens and it is a joy to use and works perfectly. I wouldn't want to jeopardize this by losing screws or misaligning the elements, etc. Better to use it, as is, and keep it dry to stop the fungus from growing. If it was a less desirable lens than the 200 mm f/5.6, I would probably have a go, as two of you suggest.
you know your right he should touch it. as he will most defiantly screw it up. Listen i have a lens with a separated element and and it is reall ugly looking and it does really affect the image. just the same i am going to separate it clean it and re glue it. I WILL LET YOU KNOW HOW IT GOES
03-31-2016, 03:33 PM   #38
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A quick follow up, separated the lens with a heat gun,and put it back together with UV clear epoxy . It was easy peasy.. And childs play at that.

03-31-2016, 03:51 PM   #39
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So I've actually done this. I left a fungusy lens in a tanning bed on high with both caps removed for 20 minutes. It wasn't anything good, not even a good performer, so it was a good test candidate. And it had live fungus in it because the colonies had grown in the three months leading up to the test.

The result: the existing colonies stopped growing. However, that led to another problem. Live fungus releases micotoxins that prevent other strains of fungus from growing. With the micotoxins absent, other funguses took hold and grew to make the problem significantly worse in the four or five weeks after the test. Those fungus colonies stopped growing after about three months, leaving me with a significantly degraded lens compared to the condition prior to UV treatment.

Don't half-donkey the repair. Take it apart, clean it, disinfect the surfaces with 91% alcohol, and reassemble. Or send it to a service center for repair.
03-31-2016, 04:01 PM   #40
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yup dont donkey it grow a pair and do the repair
04-04-2016, 07:14 PM - 1 Like   #41
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QuoteOriginally posted by K David Quote
So I've actually done this. I left a fungusy lens in a tanning bed on high with both caps removed for 20 minutes. It wasn't anything good, not even a good performer, so it was a good test candidate. And it had live fungus in it because the colonies had grown in the three months leading up to the test.

The result: the existing colonies stopped growing. However, that led to another problem. Live fungus releases micotoxins that prevent other strains of fungus from growing. With the micotoxins absent, other funguses took hold and grew to make the problem significantly worse in the four or five weeks after the test. Those fungus colonies stopped growing after about three months, leaving me with a significantly degraded lens compared to the condition prior to UV treatment.

Don't half-donkey the repair. Take it apart, clean it, disinfect the surfaces with 91% alcohol, and reassemble. Or send it to a service center for repair.
David, your experience was eye-opening. I never heard of UV radiation actually making the problem worse. I'll have to think twice about doing any irradiations myself, even though the consensus seems to be that sunlight may not help to fix a fungus problem but it wouldn't hurt. As for disassembling the lens myself and removing the fungus, I still feel that I'll end up with clean lens surfaces but a pile of tiny screws and ball bearing all over my floor. Nar, it's not worth the risk when the lens works well, as is. Maybe I'll check to see what a pro repair would cost, but the lens is only worth about $60 according to the lens reviews in the Forums.
04-04-2016, 07:19 PM   #42
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QuoteOriginally posted by psoo Quote
David, your experience was eye-opening. I never heard of UV radiation actually making the problem worse. I'll have to think twice about doing any irradiations myself, even though the consensus seems to be that sunlight may not help to fix a fungus problem but it wouldn't hurt. As for disassembling the lens myself and removing the fungus, I still feel that I'll end up with clean lens surfaces but a pile of tiny screws and ball bearing all over my floor. Nar, it's not worth the risk when the lens works well, as is. Maybe I'll check to see what a pro repair would cost, but the lens is only worth about $60 according to the lens reviews in the Forums.
I f you cant see a problem when you take a picture , then leave it alone. Cuz you are right you might mess it up
04-04-2016, 07:27 PM - 1 Like   #43
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QuoteOriginally posted by niceshot Quote
I f you cant see a problem when you take a picture , then leave it alone. Cuz you are right you might mess it up
Gotcha. Thanks
04-04-2016, 07:55 PM   #44
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Best to disassemble the lens and send each part outside the Van Allen belt for complete disinfection.
04-07-2016, 04:52 AM - 1 Like   #45
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QuoteOriginally posted by Quartermaster James Quote
Best to disassemble the lens and send each part outside the Van Allen belt for complete disinfection.
The disassembly is achievable; the van Allen irradiation is a bit more difficult; but it's the bloody loss of screws and ball bearings that's the unsurmountable problem.
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