Cleaning glass... The Neverending Story

illumiquest · Jul 22, 2011

I have a lot of lenses through which have enough dust inside that their value goes down. I'm competent enough to take most of them apart and clean them out but the problem I have is getting the glass clean. It's particularly difficult with multicoated glass. It seems like everytime I get things back together I look and I've left a small wipe mark or a bit of dust inside. I'm using ROR but have also tried denatured alcohol when cleaning things out. I'm using microfiber cloths which are clean.

Any tips on how to get things back together cleanly would be greatly appreciated.

Thanks!

brucemuir · Jul 22, 2011

Are you using gloves throughout any contact with glass cleaning cloths etc.
If even a tiny bit of any finger oils gets on a microcloth or worse...any glass surface if becomes VERY difficult to get off the glass.

It seems like it just gets moved around even when using a suitable lens safe cleaner.

Lightproof · Jul 22, 2011

My method only needs a small paintbrush consists of two steps:

1.) I use the brush soaked in isopropyl alcohol to solve oily things. Only use small amounts of liquid.

2.) To remove any residue from step 1, I apply one drop of destilled water to the glass surface and move it around with the paintbrush. You can navigate the drop quite easily over the surface and collect the last grain of dust.

Practise that with some old lens and you will get perfectly clean surfaces. The paintbrush is easy to clean and able to catch any excess pressure by its flexible tip. I never even touched a glass surface with anything else. This method is also suitable for 1st surface mirrors. Keep distance from the lens' edges.

dnjl · Jul 22, 2011

Cleaning multicoated surfaces is a real pain. You may find some answers here: (there was a url link here which no longer exists)

steven_e007 · Jul 27, 2011

I clean optics in my day job.

The biggest pain to cleaning lenses is 'Health and Safety' - with the added bonus of anti-terrorist legislation thrown in.

Every solvent that is good for cleaning glass is either too flammable, carcinogenic or suitable for use in explosives :-(

Consequently, most propriety lens cleaners these days are just water with a spot of detergent and maybe a splash of alcohol. They don't harm your lens in any way - but aren't so great at cleaning it either.

There are a few mixtures I use that get past the rules and regulations - but not sure if the components are easy enough to obtain to make it worthwhile listing them.

Ethanol might be your best bet - but it must be pure, or nearly pure. Most alcohol sold in the shops is a mixture with methanol and will have something added to make it undrinkable to alcoholics which will look and smell disgusting and always leaves residues...

I never use cloths on lenses. Personally I prefer pure cotton wool. Roll your own cotton bud, moisten, use for one sweep only and then replace. Keep everything moist to prevent scratches - work from the centre of the lens to the edge in a spiral and don't go over the same bit again with the same bud. HTH

sangetsu · Aug 6, 2011

I start by using clean tools. I wipe off my tools using lacquer thinner, and I work on a clean surface. I then carefull wash my hands to remove any oil from my fingers. Alcohol wipes are good to wipe off my hands from time to time.

To get lenses clean, I use a pure cotton Q-tip moistened with lens cleaning fluid and a touch of toothpaste. The abrasive in the toothpaste polishes glass, but can remove lens coating if used agressively. I have had good success at removing fungus from many lenses using toothpaste while not harming the coating, but it depends on the extent of the fungus. I then use a clean microfiber cloth with an ammonia/water solution, and then a new microfiber cloth for a final cleaning. I keep a blow bottle handy to blow out any dust just before setting or threading in the lens element. It usually takes more than one attempt to get the lens together with no dust specks. A magnifier is necessary to inspect the lens properly.

John Hermanson · Aug 6, 2011

Use denatured alcohol. Isopropyl (rubbing alcohol) has water in it and will leave spots. Use folded lens tissue, dip in alcohol, breathe on lens element, then wipe in circular motion from center out, blowing on element as you do it. This makes alcohol evaporate faster. It's important to use new tissue for every wipe as once a sheet is contaminated, it will streak the glass if used again. Be very careful as some older lenses (like Minolta Rokkor 58mm 1.4) have inner coatings that are SO soft, a single cleaning will rub them off, ruining the element). John

Jeff Kubach · Aug 6, 2011

I sandblast my lenses!

Jeff

Gerald C Koch · Aug 6, 2011

John Hermanson said:
Use denatured alcohol. Isopropyl (rubbing alcohol) has water in it and will leave spots. Use folded lens tissue, dip in alcohol, breathe on lens element, then wipe in circular motion from center out, blowing on element as you do it. This makes alcohol evaporate faster. It's important to use new tissue for every wipe as once a sheet is contaminated, it will streak the glass if used again. Be very careful as some older lenses (like Minolta Rokkor 58mm 1.4) have inner coatings that are SO soft, a single cleaning will rub them off, ruining the element). John

I am glad there is someone who knows what to do. Might I add that after rolling the tissue into what looks like a cigarette, tear it in two to expose the paper fibers and use these ends to clean.

Dan Dozer · Aug 6, 2011

I use Pec Pads and an optical cleaner called Eclipse (I think I got it at Freestyle). Bottle says that it contains Methanol.

Steven_E007 - does this type of cleaner seem to make sense to you. I don't seem to get any residue at all. Since you work with cleaning optics all the time, you may be the resident expert. The cleaning method it says to use is pretty much the same as what you recommend with the spiral wiping effect.

All I know is that this combination works miles better for me than conventional lens cleaner and lens cleaning paper. I used to use Kodak Lens Cleaner and lens cleaning paper and it never completely worked.

Brian Legge · Aug 6, 2011

I use a bit of Ronsonol to clean up oil which migrated to the lens. Several passes touching very lightly with PecPads (basically a tiny bit of a pad cut off, handled only with tweezers to avoid oil from fingers, one use only). The only force applied is the that of the pad bending to come in contact with the glass. Once the oil is cleaned up, I move on to either Eclipse.. sometimes just breathing lightly on the lens and then wiping it again with another clean bit of the pad. I've tried denatured alcohol at points with particularly bad glass but it usually isn't needed.

Granted, I tend to leave lenses with reputations for soft glass to the experts.

michaelbsc · Aug 6, 2011

Brian Legge said:
I use a bit of Ronsonol to clean up oil which migrated to the lens....

As I noted in another thread about this earlier today, try using Varnish Maker's and Printer's Naptha to clean. In my local store it's labeled VM&P and sold as a substitute paint thinner. It's exactly the same chemical as Ronsonol lighter fluid, only cheaper in bulk. In fact, it works great in a Zippo.

It evaporates totally, and since it is petroleum based it dissolves grease wonderfully.

Careful though. It is extremely flammable and the vapors will overcome you. It's basically highly refined light raw gasoline without the automotive additives.

I wouldn't let it pour into the lens body. See if you can disassemble it.

brucemuir · Aug 6, 2011

michaelbsc said:
Varnish Maker's and Printer's Naptha to clean. In my local store it's labeled VM&P and sold as a substitute paint thinner.

This is how the naphtha that I use for cleaning old gummed seals is marked...
VM&P.

Available at Home Despot

illumiquest · Aug 7, 2011

Thanks very much for all the input. I've started wearing non dusted latex gloves which helps quite a bit. On the last lens I cleaned I used alcohol and qtips which actually did a pretty decent job. I've also tried acetone on a couple of junk lenses which works better but also rips off the black flocking paint on the edges.

steven_e007 · Aug 8, 2011

Dan Dozer said:
I use Pec Pads and an optical cleaner called Eclipse (I think I got it at Freestyle). Bottle says that it contains Methanol.

Steven_E007 - does this type of cleaner seem to make sense to you. I don't seem to get any residue at all.

Hi Dan,

I'm not sure what a pec pad is - but if it works, it works!

I don't think it matters which alcohol type you use - the main problem with the spirit burner and rubbing alcohol type preparations is they contains colourings and perfume (probably the wrong word - they contain things to make them unpalatable). Most lens cleaners are safe to use and hopefully dry without streaks, but when you have a lens with grease on it - they are sometimes pretty useless at removing it.

Nothing, NOTHING beats chemically pure diethyl ether cut with 10% reagent grade water free ethanol. I used this mixture for years, but try walking into a drug store these days and ordering ether or pure ethanol and you are likely to leave in handcuffs. Even within the optics industry such things are virtually unattainable as almost no carrier will transport them and Health and Safety officers have palpitations over the volatility and flammability of ether.

If you can get a supply of a ethanol or petroleum benzine (or naptha - it has different names in different Countries) that is reasonably water free and has no nasty additives - that is probably the best you can do.

steven_e007 · Aug 8, 2011

illumiquest said:
I've also tried acetone on a couple of junk lenses which works better but also rips off the black flocking paint on the edges.

WHOA!!!!!!

Please do not use acetone!

It is actually pretty good at dissolving grease. Also good at dissolving paint (as you've found) and also lens balsam

Being of low viscosity capillary action will pull it into the space around the edge of the lens where it can reach the joined edges of cemented lenses and start to separate them. Also - once the acetone evaporates from the surface of the glass the paint film it leaves behind is very hard to remove...

My rule is only use acetone on single un-cemented lens elements if they are out of the mount. (Opticians use it a lot on unmounted spectacle lenses) My other rule is, on most lenses, never take the lens out of the mount...

michaelbsc · Aug 8, 2011

steven_e007 said:
If you can get a supply of a ethanol or petroleum benzine (or naptha - it has different names in different Countries) that is reasonably water free and has no nasty additives - that is probably the best you can do.

I know the vm&p naphtha from Klean Strip is extremely pure. At least according to Kleen Strip it is. They claim 95-100%, but i think it pretty consistently 100%.

Their denatured ethanol obviously has something in it. But Everclear does not.

Cleaning glass... The Neverending Story

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