The definitive, legit facts about lens cleaning... Please!

[snusmumriken]

I disagree with you on one point. I do fear that what is lost in our times is the old notion of apprenticeship. For it to happen, you need a clear trade master, a person whose authority on the matter is clear, recognized and undisputed. In the field of camera and lens repair, I fear this will become rare.

I don’t see it quite like that. The kind of mediaeval system you describe seems a certain recipe for dogma, secret knowledge and stagnation. One thing I love about our social media age is the extraordinary invention and generous sharing of ideas. Yes, there’s a lot of rubbish, often copied endlessly, but there is much good too.

Anyway, I hope some professional lens repairer chimes in for you soon.

 

[MattKing]

I disagree with you on one point. I do fear that what is lost in our times is the old notion of apprenticeship. For it to happen, you need a clear trade master, a person whose authority on the matter is clear, recognized and undisputed. In the field of camera and lens repair, I fear this will become rare.

Most apprenticeships have been modernized quite a bit - not a single trade master, but instead recognized and officially shared sources of information, combined with experienced mentors who themselves are regularly evaluated.
If you hire a modern "red seal" electrician, their apprenticeships were likely to have been quite rigorous, and involved interaction with many more than just one trade master.

 

[Dan Daniel]

I disagree with you on one point. I do fear that what is lost in our times is the old notion of apprenticeship. For it to happen, you need a clear trade master, a person whose authority on the matter is clear, recognized and undisputed. In the field of camera and lens repair, I fear this will become rare.

Yeah, it is a bit of a post-apocalyptic Mad Max world. I bet that 50 years ago you could call Kodak and they'd connect you to an optical engineer who would give you just the info you want. Now you'd just get an MBA trying to sell you a subscription to nothing. 40 year ago I was involved in a project with a museum archive and we talked to both the Kitt Peak astronomers on their technical film issues (no digital imaging) and to Kodak on spectral and exposure response of their emulsions. Got informed, science-based answers. Those days are probably gone for good.

 

[4season]

...
I do fear that what is lost in our times is the old notion of apprenticeship. For it to happen, you need a clear trade master, a person whose authority on the matter is clear, recognized and undisputed. In the field of camera and lens repair, I fear this will become rare.

We don't ask for much, do we? The history of photographic technology to date involves wood, animal skins, brass, linear motors, conductive adhesives, nano-coatings and engineering polymers. I'd characterize my own skill set as wide-ranging but shallow, while others may possess far deeper, but more narrowly specialized knowledge. For better or worse, the internet is our best approximation of a hive-mind.

 

[Arthurwg]

"It's not difficult Manuel. It's not a proposition by Wittgenstein."

I'm glad someone finally mentioned Wittgenstein.

 

[Alex Benjamin]

I'm glad someone finally mentioned Wittgenstein.

I've been waiting 5 years to finally have an excuse to do so.

the internet is our best approximation of a hive-mind.

Hive mind? Wait... You mean like...

Most apprenticeships have been modernized quite a bit - not a single trade master, but instead recognized and officially shared sources of information, combined with experienced mentors who themselves are regularly evaluated.

I see that now. Since starting this thread, I dug deeper and stumbled upon a few sites, such as fixfilmcamera.com, which not only give their own techniques and advice, but also share info from other, trusted sources. Authority is also recommendation from other authority.

 

[MattKing]

For clarity, my reference to apprenticeships was a general one. I wasn't referring to apprenticeships for camera technicians - I don't have enough information about the status of that industry.
Before she retired, my wife was very involved with programs that enabled students in public high schools to both complete their high school graduation requirements and begin their certified apprenticeships in trades like plumbers, electricians, carpenters, motor vehicle technicians, etc.
A lot of young people are graduating out of high school with good marks in science and math, as well as a partially completed apprenticeship. And the fact that they also generally have been making good money already doesn't hurt!

 

[Alex Benjamin]

For clarity, my reference to apprenticeships was a general one. I wasn't referring to apprenticeships for camera technicians - I don't have enough information about the status of that industry.
Before she retired, my wife was very involved with programs that enabled students in public high schools to both complete their high school graduation requirements and begin their certified apprenticeships in trades like plumbers, electricians, carpenters, motor vehicle technicians, etc.
A lot of young people are graduating out of high school with good marks in science and math, as well as a partially completed apprenticeship. And the fact that they also generally have been making good money already doesn't hurt!

Yes, such college-level trade schools have developed here in Quebec, available for kids who finished high school but have no interest in going to regular college or university. My daughter actually just enrolled in one, a 1.5 year program to become a motor vehicle technician. And you're right, the structure of these studies are very similar to the old apprenticeship.

 

[BrianShaw]

My city has a very robust post-secondary vocational-technical education system. Camera repair has never been an offering, though.

 

[albada]

B&H are professional retailers; does that count as "pro"?
Anyway, they have a good article on how to clean lenses:
How to Clean Your Lens and Filters

Mark Overton

 

[Dan Fromm]

Hmm. As mentioned avove (thanks, Dan) there's haze and there's haze. Some can't removed. Sad story. I once bought a supposedly good Cooke Aviar. It was hazy. So I tried all of the usual solvents. No effect. Having nothing better to do, I examined the offending surfaces under my dissecting 'scope. 40x was enough to reveal that the glass was corroded. Tiny, tiny pits all over. Oh, well.

 

[Alex Benjamin]

B&H are professional retailers; does that count as "pro"?
Anyway, they have a good article on how to clean lenses:
How to Clean Your Lens and Filters

Mark Overton

Thanks Mark. Hadn't pick up on that resource.

Been going through the links you provided on your website. Very helpful.

 

[runswithsizzers]

I see "alcohol" mentioned often, but that word covers a variety of substances. Can we assume that "alcohol" means the commonly available isopropyl alcohol? And if so, is that the 70% variety, or can the 91% and 99% concentrations also be used interchangeably?

I used to work in a hospital lab where we had ready access to isopropanol, ethanol, and methanol, and they seem to have different solvent properties. I know from experience that there are some plastics which can tolerate isopropanol, but are dissolved by methanol. Seems careless to recommend "alcohol" without being more specific.

 

[runswithsizzers]

I'm glad someone finally mentioned Wittgenstein.

I'm not so sure. I looked him up, and that's 30 minutes of my life I'll never get back. ;-)

 

[Individual One]

Currently retired, but I have a lot of years as an opto-mech integrator. Cleaning the surface of optics typically involved a progression of solvents, as the contaminant was often unidentified. My personal progression was fresh alcohol (methanol), fresh acetone (exposed stuff picks up water from the air), then ultrapure water (uncommon stuff, but we had a facility to produce it), and if that did not do the job the final step would be an optical polymer such as this stuff: https://www.newport.com/f/polymer-optic-cleaning-kits
Our really important optics were handled in a class 10 clean environment (or better).
The choice of swab is very important. They must be qualified for use on high quality optics. Crappy ones can have adhesives or other substances that can be leached out by the cleaning solvent and make the problem worse. Technique also matters. The damp swab should first contact the optic near the center, and then spiral out and lift off at the edge. This leaves any contamination marks at what is likely a less important area of the optic.
This was for the cleaning of optics and mirrors for use with high power imaging lasers. Dirt on the optic would heat up, then heat the optic, distorting it. This is not a concern with typical camera optics, where debris or haze contributes to contrast reduction but not defocusing.
Bruce

 

[snusmumriken]

I’d like to offer a couple of personal non-professional observations!

First, @Individual One used acetone as his second rank solvent. I imagine the highly technical and expensive lenses in his care were mounted in metal housings? The B&H guide referenced above (post #35) says do not use acetone on camera lenses because of its action on plastics. And on lens cements, I would add.

Second, here in the UK methanol and ethanol generally have additives to make them both recognisable and undrinkable. Reagent grades are hard to get unless you have an institutional account. But isopropyl alcohol is easily available from pharmacists or online. The lower the % of water, the better.

Third, grease passes in both directions through the swab. Wear powder-free nitrile gloves or have very clean grease-free hands. (I clean lenses straight after washing the dishes without gloves, and that works for me.)

Fourth, if you end up with smears on the lens, you may feel tempted you to rub harder, or to flood the lens with solvent, both of which are bad. It’s better to take a fresh swab moistened with a small amount of solvent and wipe lightly. Repeat until the last traces of solvent evaporate without a mark.

 

[Don_ih]

Even if you use denatured alcohol, which will leave a haze of its own behind when used to clean away some unknown crap, you can always use water after. So additives don't matter much.

I've taken apart and cleaned a few dozen lenses. I go with lens cleaner, mostly, because that's easiest to find. Spit works wonderfully well on fungus - seems to digest it - better than lens cleaner. Dish soap does a great job on grease - just ask Madge (amazing how I can recall tv commercials from the 70s....).

I once put the front element of an old Voigtlander 6x9 camera in the oven. It had what looked like a fungal infection in the balsam. I heated it up to 250 degrees and let it cool down overnight (without opening the door. That did wonders - and the lens was clear. Let's say I wouldn't do that with something that mattered.

Experimentation is fun.

One more thing, though. Don't put any liquid on an element that's still attached to the lens. Put the liquid on the wipe you're using. If you put the liquid on the lens, expect it to immediately go inside the lens.

I once bought a supposedly good Cooke Aviar. It was hazy. So I tried all of the usual solvents. No effect. Having nothing better to do, I examined the offending surfaces under my dissecting 'scope. 40x was enough to reveal that the glass was corroded. Tiny, tiny pits all over. Oh, well.

That's when you break out the pitch and cerium oxide.

 

[faberryman]

I find it fascinating that lenses have been around for almost 200 years and there is no absolute consensus on what's best to remove (or start removing) haze and fungus.

There probably is consensus among experts. Unfortunately, experts have better things to do than make YouTube videos. I'd think that the disassembly and reassembly of the lens to the appropriate tolerances would be the hard part.