Lens cleaning protocol

[Coldkennels]

(Apologies if this is a duplicate thread - the search function wasn't overly useful!)

I have a couple of lenses with haze and/or general dirty marks. I could send them all off to be cleaned professionally, but I do have lens spanners and jeweller's screwdrivers and have done a bit of repair work in the past, so the idea of stripping them down and doing it myself is not out of the question.

However, I've always avoided trying to do anything with regards to cleaning lenses out of fear of causing permanent damage, and the internet is full of mixed reports on what you can and can't use (I just watched one video where a guy removed the front element of a Helios SLR lens, washed it under the tap with dish soap, and then wiped it off with regular kitchen towel!), so I thought I'd tap up the hivemind here.

Q-tips? Isopropyl alcohol? Microfibre cloths or dedicated disposable lens tissues? Dish soap and kitchen towel? What do you use, and what should be avoided like the literal plague - especially with soft uncoated vintage lenses like Summars?

 

[Joao]

Allow me to add another question: Is the liquid used for cleaning eyglasses suitable for camera lenses ? Or should it be avoided ??

Joao

 

[Sonnar Brian]

Never dry-clean, at least breathe on the lens. Most eye-glass cleaning fluid is good, as is lens cleaning fluid.
Q-Tips: use the most gentle pressure to apply fluid with one side, wipe clean with the other.

Tiffen lens cleaning tissues the best; Kimtech Delicate Task Wipes wrapped around a Q-Tip- for large surfaces.

That is what I use.

 

[Erik van Straten]

It is best not to let the lenses get dirty.

Erik.

 

[Coldkennels]

Never dry-clean, at least breathe on the lens. Most eye-glass cleaning fluid is good, as is lens cleaning fluid.
Q-Tips: use the most gentle pressure to apply fluid with one side, wipe clean with the other.

Tiffen lens cleaning tissues the best; Kimtech Delicate Task Wipes wrapped around a Q-Tip- for large surfaces.

That is what I use.

What's your order of operations, then? I'd assume optimal process is to remove element, air blow (canned air/rocket blower), lightly dust with a lens brush, and then use a Tiffen cleaning tissue?

 

[Sonnar Brian]

I always use a Rocket Blower to get any dust off the lens. I do not use canned air. I do not use a brush, I have a few. What cleans off the brush after you use it? If I ever open a lens up, I always keep the aperture open fully. With most lenses, I keep the lens in the upright position when it is open- unless I am sure that the aperture and blades will remain in place with a ring to secure them. Never turn a Vintage Leica lens upside down, you might end up with loose blades. Be especially careful blowing air if the aperture is exposed.

 

[bluesun267]

There are some lenses whose coating is so fragile, Q-tips will damage it, particularly interior element surfaces, and first surface mirrors, such as in an SLR (or anything inside of a view/rangefinder). Generally post-1970 lens coatings are durable enough for Q-tips, but that isn't a hard and fast rule. I've found the spongy "clean room swabs" are gentler with the added bonus they don't leave little threads of cotton behind. Also Kodak lens cleaning tissue is a must for me. I don't even know if they still make it because somehow I keep finding old packs of it with the cameras I buy. I've become finicky about the kind of reusable cloths I use too. Everyday microfiber, the kind they give away with eyeglasses, has proven disastrous on more than one occasion, due to embedded dirt or other abrasive particles. The Ilford anti static cloths are better. I keep either an Ilford cloth or a high quality microfiber 'for lenses only' in a sealed ziploc. And high quality lens cleaning fluid, ala Kodak or other name brand.

So if ever in doubt about the veracity of a lens coating, start gentle:
--Lens cleaning tissue
--Clean room swabs
--Sequestered microfiber or anti-static cloth
--Good quality lens cleaning fluid

Also, your breath is nature's perfect distilled water source, so best to start there with any really questionable lens surface.

I've found plain generic windex is a just fine cleaner for modern, hard coated lenses.

Also, I know you didn't ask about this, but since I mentioned it, here's an extra warning: Use only your breath and the gentlest tissue on half mirrors associated with viewfinders...any chemical, even the mildest soap, will often erase these coatings.

Just my 2 cents

 

[Coldkennels]

Gotta thank you guys for the tips - after practicing with an old Industar, I took some time this afternoon cleaning up an old Summar that was in a horrible state. Managed to clean the first early traces of fungus off the back element, and cleaned decades worth of gunk off the front to find just two fine scratches sat underneath all the caked-on crap. It's gone from something you could genuinely barely see through to something almost presentable, which is a vast improvement. I just noticed there's still some haze inside so it'll need a proper strip-down at some point, but that's for a later day.

However, there's some weirdness on the front element - a texture or pattern that looks vaguely like a thumb print. Apologies for the bad photo - it was annoyingly difficult to capture accurately:



Anyone seen anything like this before? I'm guessing that it's probably etching from skin oils. Is this something that would need polishing and resurfacing to get out instead of just basic cleaning?

 

[Retro-Grouch]

I've seen exactly this sort of etching on old lenses, too, clear enough that the culprit could have been identified from the fingerprint! My suggestion would be to save the polishing for last, if at all. I've seen coating damage worse than this that really has had no effect on my images (although, aesthetically, it really grates on my nerves). I'd say, get the internal haze cleaned up, and shoot with the lens a bit to see if you're OK with its performance The polishing and resurfacing might get pretty expensive.
Also, be aware that some internal haze isn't accessible. Sometimes the cement between elements (whether balsam or modern synthetics) starts to get cloudy. That may or may not be repairable, at great expense, depending on the lens construction. For example, early Voigtlanders were prone to this sort of cement fogging; I had the problem with two of them in SC mount and was told by the folks at Skyllaney that I was out of luck unless I could find other lenses to cannibalize for that particular cell.
And, free plug, Skyllaney would be my first choice if I needed complex work done on any lens. Those guys are total pros and will take the time to communicate closely with you.

 

[boojum]

I always use a Rocket Blower to get any dust off the lens. I do not use canned air. I do not use a brush, I have a few. What cleans off the brush after you use it? If I ever open a lens up, I always keep the aperture open fully. With most lenses, I keep the lens in the upright position when it is open- unless I am sure that the aperture and blades will remain in place with a ring to secure them. Never turn a Vintage Leica lens upside down, you might end up with loose blades. Be especially careful blowing air if the aperture is exposed.

I am checking my lenses now.

 

[Sonnar Brian]

Gotta thank you guys for the tips - after practicing with an old Industar, I took some time this afternoon cleaning up an old Summar that was in a horrible state. Managed to clean the first early traces of fungus off the back element, and cleaned decades worth of gunk off the front to find just two fine scratches sat underneath all the caked-on crap. It's gone from something you could genuinely barely see through to something almost presentable, which is a vast improvement. I just noticed there's still some haze inside so it'll need a proper strip-down at some point, but that's for a later day.

However, there's some weirdness on the front element - a texture or pattern that looks vaguely like a thumb print. Apologies for the bad photo - it was annoyingly difficult to capture accurately:



Anyone seen anything like this before? I'm guessing that it's probably etching from skin oils. Is this something that would need polishing and resurfacing to get out instead of just basic cleaning?

Oil from fingerprints can etch into the glass. It's ugly to look at, but use a Hood and use the lens. It will not have an effect on the image, it's just you know it is there.

 

[Erik van Straten]

When cleaning lenses, always WATCH what you are doing. Invest in an instrument makers loupe or loupe glasses.

Erik.

 

[rumbliegeos]

First, I would never clean a Leica LTM lens myself, I'd leave that to professionals. My drill for other lenses is similar to ones discussed above:
1. Blow off any dust.
2. Put a small amount of lens cleaner on the lens.
3. Distribute the cleaner with an optical lens swab - Edmund Optics sells them. Store them in a clean zip-lock bag.
4. When cleaning the lens with the swab rotate the swab so fresh surfaces are on the coating or the glass as much of the time as possible; if the lens is really dusty, use multiple swabs, they are inexpensive compared with a lens or a professional cleaning.
5. When the cleaning solution is off the lens, fog it with your breath and polish it with a clean microfiber lens cloth. Keep the cleaning cloth in a small ziplock bag when not in use, and clean it in water by hand relatively frequently.

As noted above, keep lenses clean in the first place. I am usually cleaning UV or other filters, not actual lens surfaces. Btw, I adopted the optical lens swab step after watching Steve Grimes clean a Rolleiflex lens at his shop when it was in Boston - I figured he knew what he was doing.

 

[boojum]

<snip>

As noted above, keep lenses clean in the first place. I am usually cleaning UV or other filters, not actual lens surfaces. Btw, I adopted the optical lens swab step after watching Steve Grimes clean a Rolleiflex lens at his shop when it was in Boston - I figured he knew what he was doing.

I have seen the UV - Non UV discussion here and on other boards. And while the argument of, "Why put a filter which may distort in front of a good lens?" has a valid ring to it I really doubt they would still be being sold without a valid purpose. They are way cheaper than the lens and easily replaceable while the lens may not be. I just do not skimp on filter quality.

Question, what about the carbon fiber lens cleaning brushes? Are they a good tool?

 

[willie_901]

There are two general types of lens-glass surface contaminants: hydrophilic and hydrophobic.

Hydrophilic contaminants are water soluble. This means products based isopropyl alcohol will loosen and, or dissolve these contaminants. Alcohols have the advantage of evaporating much faster than water. I use Zeiss lens wipes (mostly isopropyl alcohol with proprietary detergents) to deal with hydrophilic contamination. These are inexpensive and will not damage modern lens coatings. Over-the- counter isopropyl alcohol is another option. It is important to make sure over-the- counter isopropyl alcohols products do contain lanolin or other hydrophobic components used to minimize skin drying. These additives will not evaporate or simply wipe off glass surfaces. Pure ethyl alcohol is difficult to buy. Methanol is toxic.

Hydrophobic contaminants do not dissolve in water or alcohol. Symptoms of hydrophobic lens contamination are smears and, or spots that are difficult or impossible to remove with water soluble lens cleaning products. Common sources of hydrophobic contamination are skin oils deposited by finger prints and camera component lubricants. I am very pleased with how ROR™ (Residual Oil Remover) removes hydrophobic contamination. ROR™ is designed for use on multi-coated optical surfaces.

I suppose primitive coatings on older lens may require special techniques to minimize coating loss during cleaning.

 

[hap]

There are some lenses whose coating is so fragile, Q-tips will damage it, particularly interior element surfaces, and first surface mirrors, such as in an SLR (or anything inside of a view/rangefinder). Generally post-1970 lens coatings are durable enough for Q-tips, but that isn't a hard and fast rule. I've found the spongy "clean room swabs" are gentler with the added bonus they don't leave little threads of cotton behind. Also Kodak lens cleaning tissue is a must for me. I don't even know if they still make it because somehow I keep finding old packs of it with the cameras I buy. I've become finicky about the kind of reusable cloths I use too. Everyday microfiber, the kind they give away with eyeglasses, has proven disastrous on more than one occasion, due to embedded dirt or other abrasive particles. The Ilford anti static cloths are better. I keep either an Ilford cloth or a high quality microfiber 'for lenses only' in a sealed ziploc. And high quality lens cleaning fluid, ala Kodak or other name brand.

So if ever in doubt about the veracity of a lens coating, start gentle:
--Lens cleaning tissue
--Clean room swabs
--Sequestered microfiber or anti-static cloth
--Good quality lens cleaning fluid

Also, your breath is nature's perfect distilled water source, so best to start there with any really questionable lens surface.

I've found plain generic windex is a just fine cleaner for modern, hard coated lenses.

Also, I know you didn't ask about this, but since I mentioned it, here's an extra warning: Use only your breath and the gentlest tissue on half mirrors associated with viewfinders...any chemical, even the mildest soap, will often erase these coatings.

Just my 2 cents

Just make sure lens is vaccinated before breathing on the lens. If you think that is a bad suggestion, then I pivot to Kimtech wipes.

 

[james.liam]

...or send it to someone experienced who has all that, plus fresh lubricants in their workshop and can adjust the lens with a collimator.

 

[raid]

I start out with using a Rocket Blower. Then I check if the lens is clean. If there are signs of oil smears, I then use sparingly some lens cleaner fluid on a lens cleaner paper. I gently wipe off the smears, and then I return to using the Rocket Blower. That usually does a good job in cleaning p sufficiently a lens.