Safe and effective cleaning fluids for greasy smudges on glass surfaces (1 Viewer)

[hopster]

I'm sure this has been covered before but I can't find an integrated thread - maybe it should be a sticky?

I am interested to learn to best way to clean any greasy or other smudges that might get on objective or ocular lenses on a waterproof binocular with modern coatings. My cleaning routine is usually:

1. leave until too dirty to live with, unless coming back from a harsh environment like a sea beach with salt spray/sand or very dusty/gritty place in which case do straight away
2. blow away dust and particles with an air puffer
3. rinse off lenses with clean water
4. shake off excess and wait to air dry
5. wipe gently in a spiral action with clean microfibre cloth
6. clean any remaining smudges with the appropriate fluid and microfibre cloth or cotton wool

My question is about (6). What is the appropriate fluid? Commonly I hear isopropyl alcohol and this is recommended in the Oberwerk instructions. An old photographer pro friend of mine suggested lighter fluid. Other options are acetone, simple soap/detergent (with another rinse in water afterwards) or distilled vinegar. I'm sure all will remove the smudges but I would like to know which has the least damaging effect on modern lens coatings over time. I wonder if there have been any studies on this? My gut feeling is that alcohol would be safest but gut feelings are not always correct...

 

[dries1]

The Cost of Lens Cleaners

230814 With my last thread having been generally accepted and appreciated, I feel confident to offer the following. Science teachers have been known to say that if you drop a frog into a pan of boiling water he will instantly jump out, but if you put him in the pan and slowly increase the...

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[yarrellii]

I think I probably read it here or in Cloudy Nights, but for a couple of years now I've been using Baader Planetarium's "Optical Wonder" liquid and I couldn't be happier. It deals with all sorts of dirt and it comes in a bottle that sprays the right amount (avoiding unnecessary waste).

Check it out here:

Optical Wonder™ Cleaning Fluid

100ml Optical Wonder™ Cleaning Fluid, dislodges dirt, aggressive aetherical oils from pollen and fatDries up completely without leaving any residue or wipemarkscleans without scratching: eyepieces, objective lenses – even mirrors (please see s

www.baader-planetarium.com

Just one advice (from experience), The bottle comes with a tight fitting screwable lid and the push-to-spray cap. If you are going to carry the bottle in a backpack that might be shaken or crushed (like in public transportation or on a bouncy trek) my advice is to always use the original tight fitting cap, because the other one might spill and waste some liquid (it has happened to me ).

 

[Tringa45]

A few too many steps here. If you have hard water, just leaving to dry might leave calcium carbonate or magnesium carbonate deposits.
Neither do I see any sense in postponing cleaning. Modern coatings are fairly hard and my eyeglasses are pristine after years of daily cleaning.
There are dozens of ways to avoid any damage. Here just a couple.
I always have a box of cosmetic tissues in the bathroom just fo cleaning optics.
Put a few drops of liquid detergent into water in the washbasin and clean oculars and objectives of your waterroof binocular with a tissue under water.
Dry off with a fresh tissue. If the binocular has hydrophobic coatings, just dabbing off the water droplets is sufficient.
Alternatively, after blowing or brushing off dust, spray window cleaning fluid on the tissue and wipe clean.
As Bill Cook has explained many times here, expensive cleaning fluids are a scam.

John

 

[WJC]

A few too many steps here. If you have hard water, just leaving to dry might leave calcium carbonate or magnesium carbonate deposits.
Neither do I see any sense in postponing cleaning. Modern coatings are fairly hard and my eyeglasses are pristine after years of daily cleaning.
There are dozens of ways to avoid any damage. Here just a couple.
I always have a box of cosmetic tissues in the bathroom just fo cleaning optics.
Put a few drops of liquid detergent into water in the washbasin and clean oculars and objectives of your waterroof binocular with a tissue under water.
Dry off with a fresh tissue. If the binocular has hydrophobic coatings, just dabbing off the water droplets is sufficient.
Alternatively, after blowing or brushing off dust, spray window cleaning fluid on the tissue and wipe clean.
As Bill Cook has explained many times here, expensive cleaning fluids are a scam.

John

John:

I keep bringing it up because some people just won't let the issue drop. As far as AR coatings protecting the glass beneath ... Attachment.

 

[Binastro]

Baader Optical Wonder fluid is hardly a scam at £12 a bottle, which lasts a long time.
Rother Optics or maybe First light Optics.

Unfortunately not allowed into the USA because of some ingredients.

What is a scam is the price of the well known white large tissues nowadays.

As to scams, my soap bars were £1.10 for 2 100g bars.
They are now £1.65 for two shrunk 90g bars.
As a little is left when almost used up, this is a worse scam.
Run by one of the largest companies.
Additionally, it is often not available.

This applies to many things in the U.K. now.
One can blame Brexit or just bloody mindedness on the part of the big boys.

Regards,
B.

 

[wllmspd]

I avoid cleaning unless I have to and use zeiss glasses wipes when I do and don’t rub hard. Seem to clean smears off and are cheap (glasses and phone screens get dirty far quicker than optics tend to). Avoid dousing in water or solvents unless you’re sure they won’t penetrate in or damage the paint (eg acetone).
Thought Bills favourite cleaning recipe was a mix of ammonia and rubbing alcohol?(“windex”)

Peter

 

[Tringa45]

What is a scam is the price of the well known white large tissues nowadays.

200 cosmetic tissues for €1,25. A large opticians chain uses them after ultrasonic cleaning.

Baader Optical Wonder fluid is hardly a scam at £12 a bottle, which lasts a long time.

Window cleaning spray €1,85 for 500 ml.

Both at my local drugstore. Bill has a recipe to make up a gallon for peanuts.
No reuse with the above methods. Lenspens and microfibre cloths could become contaminated.

John

 

[limonabe]

I put a drop of dish detergent in a bowl of water and jump in the shower with the binoculars. Once they're thoroughly rinsed off, I dip a piece of tissue paper in the soapy water and drag it across the lenses. Swirl it around a few times (no pressure needed,) rinse, and use a blower bulb to remove excess water once I'm out of the shower. No need to overthink the process- just take care to remove all grit and don't apply pressure and you'll be fine.

 

[Popeyethesailor]

John:

I keep bringing it up because some people just won't let the issue drop. As far as AR coatings protecting the glass beneath ... Attachment.

I have brought your book to read when on holiday in Sri Lanka in October.
I have had to resist the temptation to sneek in a few chapters before hand 🔭🙂

 

[Maljunulo]

Is it rude to ask what kind of “greasy smudges” and how they got there?

 

[hopster]

Is it rude to ask what kind of “greasy smudges” and how they got there?

Accidental touches with fingers (rare but they can happen) or gunk from eyes on the ocular lenses.

 

[hopster]

So thanks for all the replies and ideas. Still no references to scientific work which establishes which chemicals are more likely to damage modern coatings over time.

It seems like what I use on my spectacles might be just fine i.e. a little soap or dish detergent in warm water applied and then dried with a micro fibre cloth. Are paper or cotton tissues not slightly abrasive?

 

[yarrellii]

Window cleaning spray €1,85 for 500 ml.

This is really interesting, John, thanks for the tip. Could you please name a brand to have a reference of the composition so I can try to look for something similar in Spain. Over here, probably the most well known and used brand of window cleaners is «Cristasol». As per their website, it has the following composition:

AQUA, ALCOHOL, ISOPROPYL ALCOHOL, LACTIC ACID, PARFUM, METHYLCHLOROISOTHIAZOLINONE, COLORANT, METHYLISOTHIAZOLINONE, OCTYLISOTHIAZOLINONE.

I have extremely limited knowledge of chemistry, so I really can't say whether the above is good or bad for cleaning the lenses of binoculars. I think it could do without colorant and parfum, isn't it?

In fact, they have a whole range of window/glass cleaning liquids with different compositions. Here's a list of their products and the composition of each one, to see if there's any that could be of interest (I've also attached a screenshot with the list, I hope it can be readable when expanded at full size).

 

[Tringa45]

Could you please name a brand to have a reference of the composition so I can try to look for something similar in Spain.

Hi Iban,
Bill Cook suggested using Windex, but that is not available here. This is what I have used and found to be very effective:

Frosch Glass Cleaner Spirit | frosch.de

Frosch Glass Cleaner Spirit in 500 ml spray bottle ►for glass, smooth surfaces & car windows ✓ streak-free with spirit ✓ vegan ✓

frosch.de

Ingredients are biologically degradable tensides, alcohol (presumably ethanol), food colouring and water.
The only recommended restriction is not to use it on TFT screens.

Some are reluctant to use organic chemicals but I think one can dismiss the possibility of alcohols attacking the anorganic compounds used for anti-reflection coatings. The PFAS used for hydrophobic coatings (and since discontinued by Swarovski for environmental reasons) are molecules for eternity anyway.

Btw, I recall that a member here suggested using Eau de Cologne some years back. After-shave has a somewhat lower perfume content and I tried out some 4711 after-shave on my glasses to good effect. Don't think I'd make a habit of it though.

Regards,
John

 

[Hermann]

Same procedure for waterproof binoculars for well over 30 years now:

1. Rinse any dirt or salt off under running water, dry off.
2. Use a microfibre cloth if there are any persistent smudges.
3. If these smudges survive the microfibre cloth - and some of them do - I use a mixture of isopropyl alcohol and purefied water.

Never had any problems.

John: I must try Frosch ... I actually use if for my computer monitors. I think the reason they warn against it is that some really bright folks may spray it on the screen. And then some of the fluid may get into the monitor. Apparently things don't just need to be foolproof nowadays, they need to be idiotproof.

Hopster: I'm sure there are scientific studies. But they're not available to the public. Zeiss and the other manufacturers offering cleaning fluids must have made some experiments to make sure their stuff doesn't dissolve the coatings. Or the binoculars.

Hermann

 

[Binastro]

One bottle of Baader Optical Wonder Fluid lasts for years for my own use.

I don't have any hydro whats it coated binoculars, so I don't know if Baader Optical Wonder fluid is suitable.

Whether a bottle costs £2 or £12 is immaterial to me.

I also don't know how much a pint of beer costs at the pub.

I know it is 31C now and hot.

Regards,
B.

 

[Maljunulo]

Presently 32°C in Connecticut, US.

 

[wllmspd]

The only thing that will surely rot AR coatings is hydrofluoric acid, as most coatings are quite hard and unreaxtive. The modern “hard coatjngs” are pretty darn robust, I remember seeing an ad with some astro filters delisting happily is a tray of sand (Astronomik if I remember). So being careful to avoid obvious abrasives and prolonged contact with cleaning chemicals is probably all that’s needed. Of course the older the optic the greater the care as the materials will be less hard and may also have degraded somewhat through age.

Peter

 

[Binastro]

Actually my 1850s lenses have pristine glass.

It is the modern ED glasses that are more fragile and the flint elements of old refractors and fluorite crystal.
It is only the hard modern coatings that protects the glass.

Taylor's new telescope glass about 1890 was a significant improvement on older telescopes.
Unfortunately after about 7 to 10 years they needed refiguring. More so in damp climates.
Taylor more or less gave up designing for ten years because of this.

The 1930s Leica lenses were also soft at the front and had to be reworked periodically.

30 element television lenses were only possible because of coating advances.

Advanced glass tarnishes immediately it is made and has to be coated immediately.

Fungus seems able to eat modern coatings sometimes.

Regards,
B.