Lenses back from the dead!

**ismaelg** · 01-27-2020, 01:24 PM

That sound like a tough one. Can you feel them? Are you sure they are not nicks in the glass? I usually use peroxide or alcohol which you have already tried. Hmmm, as you said acetone will most likely eat the coating. Are those outside? any chance they are between elements in a group?
Tough one for sure...

Thanks,

Astro-Baby · 01-27-2020, 02:18 PM

Definitely not nicks and they arent between elements as its nit a doublet. The marks are definitely on the surface. As the coating on the lens is on the rear I have considered putting the lens face down in dish and trying to apply acetone so only the front surface gets hit. It may be the way to go.

Before I do anything else though I may run some film with it and see if its having bad effects on actual pics. To the naked eye the glass looks good this stuff only shows with a torch being shone through the lens.

Thanks though Ismael.

edom31 · 01-27-2020, 02:28 PM

Originally posted by ismaelg

Results: (with a Pentax SV)

Bit off topic, but is this el faro de Arecibo ?

**ismaelg** · 01-27-2020, 02:33 PM

Originally posted by edom31

Bit off topic, but is this el faro de Arecibo ?

Yes it is!

Praktica*ist · 01-28-2020, 01:21 PM

I have some more lenses to "save". I'm now planning to take a few photographs from a lens before cleaning it, and show them here.

What would you consider as good test subject / parameters to show the effect of fungus ? The situation should be reproducible, so I don't know...

**ismaelg** · 01-28-2020, 01:41 PM - **1 Like**

Hello,

At its initial stages, fungus really has little effect on the image. The issue is that it keeps growing if left unattended. Eventually contrast will be affected as well as overall sharpness. If you take pictures with the lens before and after, make sure to use the same parameters and conditions for a proper comparison. But I wouldn't place a fungus infected lens on a camera just to be safe.

Thanks,

Praktica*ist · 01-28-2020, 02:14 PM

Hmmm, fungus will continue to grow only if there is still moisture inside the lens. And I have no concerns about using moulded lenses in my camera, or inside my cupboard with other lenses. The issue is about moisture, not cross-contamination.

Among the infested lenses I have, there is a Pentax 200mm f/4 which is so dirty and contaminated, that you can barely distinguish the details of objects you point it into. This will be a good candidate. But I still need an idea of what to photograph...

kypfer · 01-28-2020, 03:29 PM

Originally posted by Praktica*ist

I have some more lenses to "save". I'm now planning to take a few photographs from a lens before cleaning it, and show them here.

What would you consider as good test subject / parameters to show the effect of fungus ? The situation should be reproducible, so I don't know...

A page of text from a book or newspaper is a perfectly valid repeatable test ... just remember the range the picture was taken at to get an accurate comparison.

I'm inclined to just poke my lens out of the lounge window at the roof of the building opposite. How clear the roofing tiles are can be a good indication of improvement or not, assuming there was noticeable degradation in the first place

**ismaelg** · 01-28-2020, 04:13 PM

Thinking about it, a barcode is a good subject. High contrast and sharp lines. It all depends on how close can you get.
A focus target would also be a good idea.

Thanks,

**ismaelg** · 02-01-2020, 02:07 PM - **1 Like**

Hello,

A quickie from today (2/1/2020). I got this A50 f1.7 a while back which is my favorite lens formula. Looks tired and the start of fungus under the front element.

Did not take pictures of the process but it came apart without any drama. Hydrogen Peroxide and IPA took care of the fungus. A good clean and everything went back together.

And here are some sample pictures (I swapped lenses in my K100DS).

@f11

@f8

@f1.7 wide open

Thanks,

**Sholom** · 02-04-2020, 03:40 PM

This is all very interesting. Anyone know if toluene or xylene is safe for lens coatings?

Praktica*ist · 02-10-2020, 02:29 PM

Prefer isopropyl or ethyl alcohols : they clean well the surfaces. And they are harmless for lens coatings, and most importantly, for you.

Dartmoor Dave · 02-10-2020, 03:00 PM - **2 Likes**

Originally posted by Sholom

This is all very interesting. Anyone know if toluene or xylene is safe for lens coatings?

Trinitrotoluene would probably do the trick if a lens was really stubborn about letting you disassemble it. Reassembly afterwards would be a challenge though.

Astro-Baby · 02-11-2020, 12:32 AM

I have been working on a Minolta 35mm HG and its been a cow. The front lens has been hell to get clean. Its now not perfect or anywhere close but at least you can see theough it. The second lens in has been even worse. It has a super bad haze and nothing seemed to shift it. After much experimenting it seems as if its the coating which has become damaged as its clear in places but like a fog overvthe lens. Its resisted peroxide, IPA, 4 days in acetone and a couple of applications of hand cream which was a ‘try something else as nothing else is working’ type thing. Finally after about two weeks this morning some of the fog has lifted. As the lens was useless and I had patiently polished with Q tips to no avail I thought I may as well try a technique for cleaning which is a chewed up and wet cocktail stick, its generelly safe enough if your careful and its succeeded after severeal attempts to get at least a small area clean of whatever is fogging the lens. Its now back in acetone.

As the lens is a train wreck anyway I am using it to test stuff with so its useful learning.

This is the second weird one in succession after a run of success with other lenses. No idea what the issue is but I suspect as the lens looked like someone had filled it up with oil the oil has somehow damaged the coatings. Its strange that only the front two elements have suffered like this though.

The HG seties has a rep for oil problems but its usually just an oiled up iris.

Benz3ne · 02-11-2020, 01:57 AM - **2 Likes**

A couple I've done over the last few weeks. My first, second and third foray into disassembly and cleaning (but much practice still needed)! Unfortunately no pictures but happy with the results in each case.

SMC-M 50mm f/1.7. Received with some fungus on the rear element. Simple to disassemble, cleaned up with methanol then naphtha and reassembled. Clean as a whistle now, less a little dust between the front two elements (albeit minor). Everything else works phenomenally smoothly anyway.

SMC-M 85mm f/2. Received with a hazy rear element assembly. Cleaned with naphtha, no joy. IPA, no joy. Acetone, joy. Managed to get it clear despite my initial concerns it could be element separation. Will keep an eye to make sure that isn't the case. Everything else is pristine. Little annoyed at myself for slipping a little with the lens spanner, so removing some paint from the periphery of the rearmost painted portion, but I didn't dink the lens so I'm happy.

Tokina RMC 28mm f/2.8. Received with muck, grit, a partially-removed sticker on the barrel and a sticky (read, stuck) aperture. Thought I'd use it as a practice lens seeing as they're very inexpensive. Managed to disassemble completely, cleaned up the aperture blades, cleaned out the grit and removed a little spent/congealed lubrication, reassembled, ensuring the aperture lever did operate. Initially I reassembled with the aperture dial on the squiff, so it and the focus ring were stiff. Disassembled again, snugged up with a bit more care and attention and it works smoothly, focuses correctly and stops down through all apertures as it should, as well as being clean. This one I'm annoyed I didn't take photos of...

Notes from things I've learned so far:
Always exert downwards pressure when using lens spanners. As is the case with screwdrivers, same applied to lens spanners. It really helps avoid any slipping.
If it isn't turning, don't force too much. This sounds a little counter-intuititve, but if you can't do it with reasonable force you're only likely to slip or damage something if you over-try. It's also a good recipe for stripping screws.
Get good tools. The Moody JIS screwdriver set, and 'Engineering' brand flat-head screwdriver set are both solid pieces of kit, so I'm not concerned that I'll chew up the heads.
Look at element diagrams! This will help you decide on whether to go for lenses, especially when first starting out. If it's 4 elements in 4 groups, you're not going to worry about separation.
Give yourself time. Rushing = mistakes.
Give yourself space. No room to work in = mistakes.
Wear gloves.
Know the chemicals you're handling and how to handle them safely.

I think I'll be looking to get a couple more nifty-fifties before long to clean up. I fancy an A-50/1.7 again after selling mine a while back.

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01-27-2020, 01:24 PM	#31
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	That sound like a tough one. Can you feel them? Are you sure they are not nicks in the glass? I usually use peroxide or alcohol which you have already tried. Hmmm, as you said acetone will most likely eat the coating. Are those outside? any chance they are between elements in a group? Tough one for sure... Thanks,

01-27-2020, 02:18 PM	#32
Astro-Baby Veteran Member Join Date: Nov 2018 Location: Reigate, Surrey Posts: 764	Definitely not nicks and they arent between elements as its nit a doublet. The marks are definitely on the surface. As the coating on the lens is on the rear I have considered putting the lens face down in dish and trying to apply acetone so only the front surface gets hit. It may be the way to go. Before I do anything else though I may run some film with it and see if its having bad effects on actual pics. To the naked eye the glass looks good this stuff only shows with a torch being shone through the lens. Thanks though Ismael.

01-27-2020, 02:28 PM	#33
edom31 Pentaxian Join Date: Nov 2017 Location: Garden City, NY Photos: Gallery Posts: 6,349	Originally posted by ismaelg Results: (with a Pentax SV) Bit off topic, but is this el faro de Arecibo ?

01-27-2020, 02:33 PM	#34
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Originally posted by edom31 Bit off topic, but is this el faro de Arecibo ? Yes it is!

01-28-2020, 01:21 PM	#35
Praktica*ist Forum Member Join Date: Jan 2013 Location: France, near Paris Posts: 57	I have some more lenses to "save". I'm now planning to take a few photographs from a lens before cleaning it, and show them here. What would you consider as good test subject / parameters to show the effect of fungus ? The situation should be reproducible, so I don't know...

01-28-2020, 01:41 PM - 1 Like	#36
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Hello, At its initial stages, fungus really has little effect on the image. The issue is that it keeps growing if left unattended. Eventually contrast will be affected as well as overall sharpness. If you take pictures with the lens before and after, make sure to use the same parameters and conditions for a proper comparison. But I wouldn't place a fungus infected lens on a camera just to be safe. Thanks,

01-28-2020, 02:14 PM	#37
Praktica*ist Forum Member Join Date: Jan 2013 Location: France, near Paris Posts: 57	Hmmm, fungus will continue to grow only if there is still moisture inside the lens. And I have no concerns about using moulded lenses in my camera, or inside my cupboard with other lenses. The issue is about moisture, not cross-contamination. Among the infested lenses I have, there is a Pentax 200mm f/4 which is so dirty and contaminated, that you can barely distinguish the details of objects you point it into. This will be a good candidate. But I still need an idea of what to photograph...

01-28-2020, 03:29 PM	#38
kypfer Pentaxian Join Date: Jan 2018 Location: Jersey C.I. Posts: 3,594	Originally posted by Praktica*ist I have some more lenses to "save". I'm now planning to take a few photographs from a lens before cleaning it, and show them here. What would you consider as good test subject / parameters to show the effect of fungus ? The situation should be reproducible, so I don't know... A page of text from a book or newspaper is a perfectly valid repeatable test ... just remember the range the picture was taken at to get an accurate comparison. I'm inclined to just poke my lens out of the lounge window at the roof of the building opposite. How clear the roofing tiles are can be a good indication of improvement or not, assuming there was noticeable degradation in the first place

01-28-2020, 04:13 PM	#39
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Thinking about it, a barcode is a good subject. High contrast and sharp lines. It all depends on how close can you get. A focus target would also be a good idea. Thanks,

02-01-2020, 02:07 PM - 1 Like	#40
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Hello, A quickie from today (2/1/2020). I got this A50 f1.7 a while back which is my favorite lens formula. Looks tired and the start of fungus under the front element. Did not take pictures of the process but it came apart without any drama. Hydrogen Peroxide and IPA took care of the fungus. A good clean and everything went back together. And here are some sample pictures (I swapped lenses in my K100DS). @f11 @f8 @f1.7 wide open Thanks,

02-04-2020, 03:40 PM	#41
Sholom Loyal Site Supporter Join Date: Dec 2011 Location: Massachusetts Photos: Gallery Posts: 125	This is all very interesting. Anyone know if toluene or xylene is safe for lens coatings?

02-10-2020, 02:29 PM	#42
Praktica*ist Forum Member Join Date: Jan 2013 Location: France, near Paris Posts: 57	Prefer isopropyl or ethyl alcohols : they clean well the surfaces. And they are harmless for lens coatings, and most importantly, for you.

02-10-2020, 03:00 PM - 2 Likes	#43
Dartmoor Dave Pentaxian Join Date: Aug 2012 Location: Dartmoor, UK Photos: Gallery Posts: 3,882	Originally posted by Sholom This is all very interesting. Anyone know if toluene or xylene is safe for lens coatings? Trinitrotoluene would probably do the trick if a lens was really stubborn about letting you disassemble it. Reassembly afterwards would be a challenge though.

02-11-2020, 12:32 AM	#44
Astro-Baby Veteran Member Join Date: Nov 2018 Location: Reigate, Surrey Posts: 764	I have been working on a Minolta 35mm HG and its been a cow. The front lens has been hell to get clean. Its now not perfect or anywhere close but at least you can see theough it. The second lens in has been even worse. It has a super bad haze and nothing seemed to shift it. After much experimenting it seems as if its the coating which has become damaged as its clear in places but like a fog overvthe lens. Its resisted peroxide, IPA, 4 days in acetone and a couple of applications of hand cream which was a ‘try something else as nothing else is working’ type thing. Finally after about two weeks this morning some of the fog has lifted. As the lens was useless and I had patiently polished with Q tips to no avail I thought I may as well try a technique for cleaning which is a chewed up and wet cocktail stick, its generelly safe enough if your careful and its succeeded after severeal attempts to get at least a small area clean of whatever is fogging the lens. Its now back in acetone. As the lens is a train wreck anyway I am using it to test stuff with so its useful learning. This is the second weird one in succession after a run of success with other lenses. No idea what the issue is but I suspect as the lens looked like someone had filled it up with oil the oil has somehow damaged the coatings. Its strange that only the front two elements have suffered like this though. The HG seties has a rep for oil problems but its usually just an oiled up iris.

02-11-2020, 01:57 AM - 2 Likes	#45
Benz3ne Pentaxian Join Date: Jun 2019 Location: Cymru Posts: 2,356	A couple I've done over the last few weeks. My first, second and third foray into disassembly and cleaning (but much practice still needed)! Unfortunately no pictures but happy with the results in each case. SMC-M 50mm f/1.7. Received with some fungus on the rear element. Simple to disassemble, cleaned up with methanol then naphtha and reassembled. Clean as a whistle now, less a little dust between the front two elements (albeit minor). Everything else works phenomenally smoothly anyway. SMC-M 85mm f/2. Received with a hazy rear element assembly. Cleaned with naphtha, no joy. IPA, no joy. Acetone, joy. Managed to get it clear despite my initial concerns it could be element separation. Will keep an eye to make sure that isn't the case. Everything else is pristine. Little annoyed at myself for slipping a little with the lens spanner, so removing some paint from the periphery of the rearmost painted portion, but I didn't dink the lens so I'm happy. Tokina RMC 28mm f/2.8. Received with muck, grit, a partially-removed sticker on the barrel and a sticky (read, stuck) aperture. Thought I'd use it as a practice lens seeing as they're very inexpensive. Managed to disassemble completely, cleaned up the aperture blades, cleaned out the grit and removed a little spent/congealed lubrication, reassembled, ensuring the aperture lever did operate. Initially I reassembled with the aperture dial on the squiff, so it and the focus ring were stiff. Disassembled again, snugged up with a bit more care and attention and it works smoothly, focuses correctly and stops down through all apertures as it should, as well as being clean. This one I'm annoyed I didn't take photos of... Notes from things I've learned so far: Always exert downwards pressure when using lens spanners. As is the case with screwdrivers, same applied to lens spanners. It really helps avoid any slipping. If it isn't turning, don't force too much. This sounds a little counter-intuititve, but if you can't do it with reasonable force you're only likely to slip or damage something if you over-try. It's also a good recipe for stripping screws. Get good tools. The Moody JIS screwdriver set, and 'Engineering' brand flat-head screwdriver set are both solid pieces of kit, so I'm not concerned that I'll chew up the heads. Look at element diagrams! This will help you decide on whether to go for lenses, especially when first starting out. If it's 4 elements in 4 groups, you're not going to worry about separation. Give yourself time. Rushing = mistakes. Give yourself space. No room to work in = mistakes. Wear gloves. Know the chemicals you're handling and how to handle them safely. I think I'll be looking to get a couple more nifty-fifties before long to clean up. I fancy an A-50/1.7 again after selling mine a while back.