Recommend a glass cleaning technique

[foto_mike]

So, about the same time I picked up the apparently unused Speedex Special R folder (described in another thread), I picked up an Isolette III in nice condition as well. This one has been used, but it's in very nice condition. It has the standard frozen front lens cell and a stiff, out of alignment rangefinder. I'm fine tuning my CLA technique on this one before I tackle the my Special R.

I've disassembled and reassembled a couple of Isolette I cameras (Agnar) in the past to see how things come apart. I'm pretty good at removing a frozen front cell without damage and I can extract the lens elements from their mounting rings with no problem. I did all of this to my Isolette III last night, however, I really struggled to get the glass as clean as new.

What is the best glass cleaning technique for these old lenses?

I started with Eclipse cleaning solution and Pec-Pads. The glass looked great until I carefully examined it at an angle where I could get a reflection off the surface. I could see what looked like a very subtle multi-colored oil smudge. I tried a no-name lens cleaning solution and it didn't help much. I even tried mild soap and water. That made it better, but still not as clean as I'd like.

Looking straight through the lens element in good light, I can see nothing. It's probably good enough to have no affect on the photos, but I'd like it as close to perfect as possible. Is there a better solvent or technique?

 

[bmattock]

The best lens cleaning solution I have found is ROR (Residual Oil Remover). Not cheap, but worth it for very dirty / oily lenses.

http://www.bhphotovideo.com/c/product/439303-REG/ROR__Residual_Oil_Remover.html

I normally do not need it, so a small bottle has lasted me ages.

For regular filth on lenses, I use Kinetronics Precision Glass Cleaner.

 

[literiter]

I've had some success with a product called "Quantaray" precision cleaning solution. It contains isopropyl alcohol and I don't know what else.
(I wonder if it isn't the same as the Kinetronics stuff.)

The coating on some of the inside lenses on early (Super Ikonta for sure) folding cameras can be almost wiped off with some lens cleaners, so use caution.

 

[Solinar]

If you have the lens already apart, I'd give the elements a wash with high grade ethanol and then wipe a slightly moistened microfiber cloth.

With regard to ROR - spray the cloth, not the lens for a final cleaning.

 

[FallisPhoto]

So, about the same time I picked up the apparently unused Speedex Special R folder (described in another thread), I picked up an Isolette III in nice condition as well. This one has been used, but it's in very nice condition. It has the standard frozen front lens cell and a stiff, out of alignment rangefinder. I'm fine tuning my CLA technique on this one before I tackle the my Special R.

I've disassembled and reassembled a couple of Isolette I cameras (Agnar) in the past to see how things come apart. I'm pretty good at removing a frozen front cell without damage and I can extract the lens elements from their mounting rings with no problem. I did all of this to my Isolette III last night, however, I really struggled to get the glass as clean as new.

What is the best glass cleaning technique for these old lenses?

I started with Eclipse cleaning solution and Pec-Pads. The glass looked great until I carefully examined it at an angle where I could get a reflection off the surface. I could see what looked like a very subtle multi-colored oil smudge. I tried a no-name lens cleaning solution and it didn't help much. I even tried mild soap and water. That made it better, but still not as clean as I'd like.

Looking straight through the lens element in good light, I can see nothing. It's probably good enough to have no affect on the photos, but I'd like it as close to perfect as possible. Is there a better solvent or technique?

STOP!!!!!!!!!!! If it is an uncoated lens, and the stuff on your lens looks like an irridescent film of oil on water, that is called "bloom." It is a type of tarnish or oxidation that develops naturally on some types of glass. It is what artificial lens coatings were created to copy, and it is desirable. Don't clean it off! It (at very least) doubles the value of the lenses on your camera.

Edit: The effects that natual "blooming" will have on a lens are that it will increase light transmission and contrast.

 

[sniki]

Try also Zeiss pre-moistened lens cloth by Carl Zeiss Optical, Inc.
They are ammonia-free formula.

sniki

 

[sevo]

What is the best glass cleaning technique for these old lenses?

I started with Eclipse cleaning solution and Pec-Pads. The glass looked great until I carefully examined it at an angle where I could get a reflection off the surface. I could see what looked like a very subtle multi-colored oil smudge.

Sorry, but are you aware of the existence of coatings and their look? All Isolette III's (and all Isolette I's - except for the lookalike but unnumbered pre-war Isolette with Agnar/Igestar lens) have coated lenses.

Sevo

 

[sniki]

Moreover, Zeiss pre-moistened lens cloth are especially designed for lens with anti-reflective multi-layer coatings.

sniki

 

[fidget]

Be careful when cleaning stubborn mark on lens elements.
Probably not the case here, but I once cleaned the elements from my Solinar Isolette. One mark, like a "tide mark" just would not shift.

After a dunk in several increasingly vicious cleaning solutions I realised that the mark was between two cemented elements. When I'd finished it was ten times worse......

 

[foto_mike]

Sorry, but are you aware of the existence of coatings and their look? All Isolette III's (and all Isolette I's - except for the lookalike but unnumbered pre-war Isolette with Agnar/Igestar lens) have coated lenses.

Sevo

Truthfully, I'm not so sure what to expect the lens coating to look like. It certainly doesn't look like the coatings on a modern lens, but I don't suppose I'd expect that.

I don't want to damage the lens. Nothing but Pec-Pads, Eclipse, and mild soap and water have touched the elements so far. I stopped there to seek advice before I became more aggressive.

I know what a lens element looks like when you smudge it with a fingerprint. The natural oils from your finger tend to make a multicolored streak. This looks a bit like that, although much more subtle and more evenly distributed across the surface. It wasn't so evenly covering the whole surface, though, to make me think it was the lens coating. It was ragged around the edges and covered the entire center of the element.

The front element is convex on the front surface and flat on the back surface. I can see it on the reflection of the flat surface. It's very hard to get a reflection off the convex surface. Maybe because it's coated? Maybe because the reflection of a curved surface is very small.

When the lens is assembled into the shutter, I can't see any of the markings I'm describing. It actually looks very good and I should probably just leave it at that. Maybe I should leave my question as, what is the best practice for cleaning 1950's era lens elements once they are disassembled from the shutter?

 

[FallisPhoto]

Maybe I should leave my question as, what is the best practice for cleaning 1950's era lens elements once they are disassembled from the shutter?

Okay, you've got tissues, microfiber cloths and other methods. I've been seeing some threads on lens cleaning that recommend lens tissues. This is a cheap and convenient way to do it, but it is also risky. Tissues trap dust and grit between lens and tissue and it is all too easy to scratch the lenses. Some lens tissues, meant for eyeglasses, are actually mildly abrasive and can scratch soft-coated lenses with no help from trapped grit. Microfiber lens cloths are safer, but still not 100% safe. So how do you do it?

Well, first you go over it with a blower and a soft lens brush, to remove as much grit as possible.

Next you are going to need some solvents. Commonly used solvents used in camera restoration (and lens cleaning) are:
1. denatured alcohol, used to remove tar (from cigarettes, or pine pollen) and detriorated light seal material (sometimes found stuck to rear lens elements). Do NOT use rubbing alcohol; it will work, but it is not a benign solvent and it can attack some balsam cements used to glue lens elements together. In addition, it is far from pure and can contain all sorts of crud. The idea is to get that sort of thing off of the lens.
2. naphtha (Ronsonol lighter fluid), used to remove grease and oils (naphtha is REALLY good for fingerprints).
3. distilled water, used to remove everything else.

These are all benign and won't harm your camera if you just keep them out of the electronics and don't actually SOAK the camera in them.

4. One other special solvent: a 50/50 mix of hydrogen peroxide and ammonia, used to kill and remove lens fungus. For soft-coated lenses you will dillute this to about 10% strength. Full strength is usually okay for lenses made after the mid-70s though.

Then you get a big box of Q-tip cotton swabs. Dampen a swab with your solvent of choice, and start in the center of the lens, working outward. A little solvent goes a long way, so you want your swab to be damp, not wet. Use gentle pressure, not much more than the weight of the Q-tip. Don't scrub, but let the solvent do the work. Twist the swab as you go, so that a fresh surface is kept in contact with the lens and any grit is lifted away from the glass, not rubbed against it. You'll go through quite a few Q-tips. I generally go over my lenses, when they are really dirty -- or have just come from ebay, two or three times with at least the naptha and the distilled water.

When you use the naphtha, you may notice a haze forming on your lens as it dries. Don't panic; this is a GOOD thing. Naptha is slightly base. The haze is what happens when you mix oil and grease with a base; you just made soap. The naphtha itself leaves no residue. When you go over the lens with the distilled water, it will remove the haze.