"Can I use Rain-X on my binoculars or riflescopes?"
That's a common question you may hear from hunters, but they're not the only ones who wear corrective lenses and wonder about using this popular product. Anglers, bikers, hikers, trail runners, birdwatchers, skiiers, snowboarders and competitive shooters at some point have issues with rain and humidity.
In summer 2019 while doing a trail running event, my glasses became terribly and consistently fogged from humidity. It was miserable not being able to see clearly. I tried some of the highly recommended Cat Crap anti-fog cleaner, but initially that didn't work as well as I'd like. I'm still giving it a try. My next option is this Oakley cleaning and water-repelling unit. We'll see how that goes.
I've used Rain-X products on my vehicle's external glass for years, including the wiper blades. Rain-X is a synthetic, temporary hydrophobic product that causes water to bead on glass and some other surfaces. On the the company's FAQ page, a couple of good questions are answered including about whether Rain-X products can be used on acrylic, tinted windows, home windows and solar panels, among other items.
Regarding use on tinted glass and Rain-X's Anti-Fog product, the company's FAQ response is, "No. This product needs to be used on clear glass that is void of anything else on it such as tints."
Considering most hunting and sporting optics have internal and external multi-coated optics, that might rule out use on binoculars, riflescopes and spotting scopes. Right?
"It won’t damage a binocular glass lens if used once or twice," says Mike Jensen with German Precision Optics. "BUT, it is a chemical and alcohol-based product and will rather quickly erode the hard and permanent micron-thin GPObright coatings that are applied in a vacuum chamber."
For the best results and to achieve longevity, Jensen said, the optimal care "is to keep your lenses dry as possible, and clean them with a mild eyeglass lens cleaner, (soft) brush and micro(fiber) cloth."
That means no spit, paper towels or toilet paper, or dirty t-shirts scrubbed across the bino or scope lens. Don't, don't, don't. If you sell binoculars, riflescopes or spotting scopes in your store, consider stocking a supply of microfiber cleaning cloths and lens cleaner.
Display these cleaning supplies prominently by the optics display, and also put a smaller display by the check-out register. If they didn't pick up either at the optics area, the reminder at check-out could nudge them to buy.
Dean Capuano, director of communications for Swarovski Optik NA, travels around the country and world for work. He also travels as host of Swarovski Optik Quests. Whether he's knocking down 150-inch whitetails in Kansas or high on a mountain in Europe, his optics must perform in all weather conditions.
Swarovski's optics have numerous coatings to enhance light transmission, clarity and battle the elements. Those of GPO, Bushnell, Styrka and others do, too. The "multi-coated" pronouncements have varying degrees, depending on price, but almost all optical tools today have coatings.
Capuano said that includes hydrophobic coatings, too, making Rain-X or other anti-fog treatments unnecessary.
"You can use it but many of the scopes have coatings specifically designed to help that already," he said. "We really don’t recommend it but It really won’t hurt anything."
Matt Rice, senior manager of media relations and consumer marketing for Bushnell at Vista Outdoor, spoke with the company's optics engineers. Rice said "no one has personally done it" and it falls into their idea of "should you?" vs. "can you?"
"Yes you can," Rice said, "but it’s not something we would recommend." He noted the Rain-X recommendations to not use on certain types of materials or coated lenses lenses. "I presume the concern is it could cause issues with other lens coating, causing interference with light transmission, image distortion/overall clarity, resolution and contrast.
"Almost all of our optics already come with a protective lens technology that is molecularly bonded to the glass – EXO Barrier. This coating is hydrophobic and oleophobic. It also has a thicker molecular structure and does not have to be reapplied. It is designed to last the lifetime of the optic.
"So, while you could technically use (Rain-X), I think there are safer alternatives including selecting a manufacturer that already has a strong reputation and experience in this matter."
Bottom line? To me, it's easy and easy to relate to customers.
Today's top binoculars, riflescopes and spotting scopes have solid technological aspects that don't need extra help. When customers ask, your best answer may be that if they're spending their hard-earned money for lenses that already have multiple coatings, why risk it?
