One of the major flaws of these new coatings is the strict admonition to never, ever, wipe the coated surface dry. Never! And if you break this “suggestion” you’ll be cursed with a coating that is compromised. In other words, you broke the rules so now it won’t work as reliably.
Now there is an aftermarket cure that works well to fight lenses fogging up. It’s called Sven Can See™ and it’s good for glasses, ski goggles, even swim goggles. It’s a simple spray on liquid that you apply to the inner lens of whatever eye-wear you need to fight fogging up.
When I first tried it out the prospect of snow was still months away, but swimming is the foundation of my workout routine. Over the years having fog-free goggles has been a rare exception, not the rule. My first trial run I didn’t bother waiting for the liquid to dry, I just sprayed a drop on one lens, smearing it around with a finger, then with the excess, smeared the other lens and headed for the water. After two months swimming laps I’m completely spoiled now with the ability to see lane markers clearly the full length of an Olympic sized pool.
The directions for Sven-Can-See™ say to spray the goo on the lens, then spread it around with a clean finger and let it dry. In the case of sunglasses or ski goggles, smearing it around with your finger does not yield a smooth, evenly coated surface. If you just let it dry, the variations in thickness will yield a distorted view. To eliminate that, use a dry, clean cloth to polish it smooth.
Keeping the fog off of swim goggles is pretty impressive, but the temperature variation between the inside and outside of goggles in a pool is far less than on cold winter’s day. Next test was my prescription sunglasses which fog with disturbing regularity when skinning up a snow covered slope.
On two successive days skinning in single-digit temperatures with little to no wind, a classic formula for fogged vision in my experience, I was impressed at how well Sven’s magic potion allowed me to see. My sunglasses did fog up every time I stopped moving and the light wind from moving ceased and sweat continued to pour out my pores. Ordinarily I’d have to remove ‘em and wipe ‘em clean, and pray they’d stay clear as I continued moving. With the Sven-Can-See coating on the inside the lenses cleared within a minute of moving again. In my experience, that’s impressive visual performance, worth adding to a backcountry skiers bag of tricks.
Just remember, a little dab’ll do ya. You don’t need to blob Sven Can See™ all over, a single drop will cover two glass lenses, but it might take two drops for a pair of goggles.