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What should I clean binocular lenses with? (1 Viewer)

WJC ask any optician and they will tell you Alcohol can harm lens coatings. Years ago there were no coatings on bino lenses so it didn’t matter. There are plenty of more advanced alcohol free lens cleaners available now that are designed not to harm coatings. If one wants to use old style alcohol cleaners so be it. I choose to follow experts advice and use the most advanced products available. Go ahead and have the last word. I’m sure it will be most enlightening.
See Post 27.

Upland, My friend, I don’t need to have the “last word.” Reality and a number of knowledgeable people in the field have done that for me. As I said earlier, please feel free to clean YOUR optics with anything from horse dung to sandpaper. Perhaps you’re willing to go to your grave believing the foolish. If so, please, go for it.

Some folks come to these forums to LEARN, GROW, and SHARE—raising the bar of optical understanding. Others come to pontificate the irrelevant to idiotic and see how many people they can sway to their way of thinking. With thousands of professional technicians and Ph.Ds. standing behind me, I think I’ll stay with my poor misguided understanding of things. * I visit several optics/binocular forums and can say BF is by far the top of the mark.

To some folks, these forums are just a place to see and be seen, where it’s all about each OPINION being as valid as the next. However, although you will encounter a few wingnuts, overall you will find the members of BirdForum a cut above—people who generally realize all that glitters is not gold.

“The truth is incontrovertible. Malice may attack it, ignorance may deride it, but, in the end, there it is.” Winston Churchill

* Attachment #1 And if you ever run out of things to worry about—and you missed all the reading in post #13. You may note, I used acetone FAR MORE than alcohol—as do Al and Dave Nagler, Gary Hawkins, and myriad other professionals. The attached is from the afore mentioned post.

“But acetone will remove coatings” ... NOT! That’s a product of abrasion on poor coatings.

“But acetone causes cancer” ... NOT! I’ve discussed this with MEDICAL professionals. Acetone is manufactured in our bodies.



PS As often as not, the opticians defer to me in this matter. Please see attachment #2.


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Interesting that people are accused of 'provocation' and 'trolling' merely for expressing their own opinion instead of bleating with the chorus or blowing smoke up self-appointed experts' arses. One more for the ignore list methinks.
Interesting that people are accused of 'provocation' and 'trolling' merely for expressing their own opinion instead of bleating with the chorus or blowing smoke up self-appointed experts' arses. One more for the ignore list methinks.

Everyone is entitled to their own opinion. They aren't entitled to their facts.

If you are proven wrong, admit it and move on.
Binocular cleaning has two aspects, the objectives and the oculars.
The former pick up rain, dust and spray, the latter mostly rain and sweat.
A quick swipe with the tongue will clean oculars pretty well, as saliva cuts grease nicely and the tongue provides the soft, non scratching support that is needed.
The objectives rarely need cleaning, as even big blobs hardly affect the image, something WJC has demonstrated.
However, when the salt or dust builds up excessively, a careful rinse, a lick and then another rinse and a pat to dry will leave the surface in good shape.
There is little need to buy nostrums or detergents unless one is cleaning binoculars professionally.
Interesting that people are accused of 'provocation' and 'trolling' merely for expressing their own opinion instead of bleating with the chorus or blowing smoke up self-appointed experts' arses. One more for the ignore list methinks.
John is absolutely right. When people ignore testament after testament of knowledgeable members, and BF has several—including the moderator—the testaments of professional opticians with decades of experience, testaments from companies like Zeiss, Leica, and Swarovski, and testaments from persons quoted, it appears they’re just looking for someone—ANYONE—to confirm their ludicrous assertions, or for a reason to put on the gloves. Life is too short, and I have neither the need nor reason to continue. Trying to offer a little rational help in this instance has become like trying to push Gibraltar uphill ... one-handed... while wearing skates ... at night ... without a flashlight ... in a gale.

I do respect his desire to believe ANYTHING he wants. But if alcohol takes off AR coatings from his binocular—with them being harder than the glass beneath—he should spend more than $29.95 on another instrument and upgrade the level of experience coming from his expert advisors.
A quick swipe with the tongue will clean oculars pretty well, as saliva cuts grease nicely and the tongue provides the soft, non scratching support that is needed.
Reminds me of spitting into the goggles and wiping them before diving to cut down on condensation.
Gentlemen this bickering is unseemly. Anybody who wants to know what a professional repairer is using to clean lenses can simply visit post 27. Anyone can buy lens cleaner, cloths and brushes from dealers. Let's move on.

I used to rescue very large aerial lenses that had been buried in mud for decades.
They were opaque.

Sometimes with large amounts of water and time, the came up beautifully.

I had one, a 4 element TTH 20 inch f/5.6 Aviar that proved impossible.
I tried toothpaste to no avail.
So then I used Brasso.
Within 30 seconds the grime was gone.
But I had destroyed the lens.
The surface figure was destroyed and star test awful.

There was another, a Zeiss Survey lens 75cm f.6.3 Telikon that I rescued from a tip with many iron girders in it.
The front surface had numerous large gouges where the iron girders had done their work. These made up half the area.
However, star testing showed that the beautiful figure was still maintained but with a tremendous loss of contrast.

The Ross Xpress E.M.I. 20 inch f6.3 WA lenses from about 1955 had very soft internal coatings.
When cleaning the fungus all the coating came off also.

Nowadays I mainly use Baader Optical Wonder fluid.


A couple of people have asked me how I feel about those who, after reading my treatise on cleaning optics, continue with this and that solution, ad nauseum.

First, that’s just human nature and in 16 years of visiting these forums, I’ve experienced no other way. My best explanation comes from my long-deceased dad.

He was in a department store to buy some new work shoes in the late 1940s, when a couple of fellows on a trek from Detroit to Atlanta came in to buy one of them a new shirt. His fountain pen had leaked, and he had to have a new shirt before going to a job interview.

The fellow decided on a silk shirt that he really liked, but there was a problem; this shirt cost about $1.25 and he had to have something better. Asking the salesman if he had anything else that was similar but better. The clerk replied he felt he might have a couple in the back that would do the trick. So, he took the shirt, for comparison, and headed to the storeroom. After an inordinate amount of time, he returned with a new shirt in a box. This shirt would fill the bill, perfectly. Not only that, the package was plainly labeled $4.00 which, of course, was what the customer really wanted.

With the two smiling and happily out the door, the clerk, who had long known my dad, told him the “rest of the story.” He had taken the $1.25 shirt to the storeroom, put it in a different box, and stuck a new label on it. When my dad queried him further, he said, “The man liked the shirt; he just didn’t like the price. So, I gave it to him at a price he WOULD like. That’s just good customer service.”

To understand more, I offer the following:

I had just started ATM Journal when I asked editor Harrie Rutten (Telescope Optics Evaluation & Design) if he would pass out some copies in the astronomy groups he frequented in the Netherlands. He said that would be counterproductive because if he passed them out FREE, Netherlanders wouldn’t consider the act promotional but, since given away, would consider them of no value!

Unlike today’s news media, I’m just reporting and not passing judgment.

If you're gonna repeatedly pick up liquid cleaning product chemical residue from the oculars with your eyelashes, and drag it into close contact with your eyes, the stuff you use had better be friendly. That is one big difference between camera lenses and binocular oculars.

A way to reduce the problem I've done for years is to keep my eye brows trimmed short. I'm old and married so looks aren't mission critical ;)
Leica advises to NEVER use alcohol, nor any chemical cleaners on their optics, so I guess that Zeiss Lens Cleaning Tissues are a no-no, on Leica glass anyway.

Zeiss advises to use breath moisture when cleaning their glass, with a soft, lint-free cloth.

So, I guess if one were to use Zeiss Lens Cleaning tissues, it may be wise to do so sparingly.
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I use mild solution of dawn soap and warm water and wash off dust particles before cleaning the lense with a microfiber cloth.

lately I don't even wipe it off, just shake off any water drops due to lenses being hydrophobic.
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