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Buying Right: Polarized Sunglasses
By Bob Howells

Shading against the beach sun means dark specs, a broad-brimmed hat, and a frill-edged umbrella. Shielding against that sun, however, means polarized glasses.

There’s a big difference between polarized lenses and all others. When sunlight reflects off water, snow, or sand, it concentrates into a single plane–as opposed to bouncing around in the scattered-light norm–creating a piercing beam of brightness that regular darkened lenses can’t keep out. Polarized lenses, however, work something like venetian blinds: A thin film in the
lenses is imbued with small crystals that are carefully aligned to remove most of the offending glare without blocking out all of the light.

Polarized sunglasses let you spot subsurface brookies and wind patterns on the bay, and they’re a good choice for driving, since they filter out pavement glare. Why aren’t all sunglasses polarized? Cost. The film is hard to get right and must be specially molded or laminated to the lenses. The models I tested range in price from about $125 to over $300.

When shopping for polarized shades, all of the usual criteria apply: Look for 99 to 100 percent ultraviolet absorption, 12 to 17 percent light transmission, and–my opinion here–glass lenses. They may be a tad heavier and more expensive than plastic, but glass specs are also likely to be more distortion-free and scratch-resistant. Choose gray or green lenses to see more
realistic colors, brown or amber to heighten contrast.

For true-color viewing, the value choice is Ray-Ban’s Cats 3000 ($129). The plastic frames are sturdy and provide decent coverage with medium-size cat-eye-style rims. Revo’s Grand Sixties frame, fitted with its H₂0 lenses ($205), looks Cats-like and does everything a little bit better: The nylon frame fits
snugly, the lenses do an exceptional job of cutting glare, and, thanks to high-quality lens coatings, the clarity is superb. From Ray-Ban, 800-472-9226, and Revo, 800-843-7386.

I tried three polarized sunglasses that are also photochromic, which means they get darker or lighter as conditions demand. The nylon-frame Hobie Cabo ($124) and Smith Kootenay ($150), as well as the metal-frame Serengeti Strata ($330), all have generously sized brown-or copper-tinted
lenses. The sturdy Cabo is a bargain buy and comes in a stylish tortoise shell color, the Kootenay is light on your face, and the Strata, thanks to an additional filter and coatings, is as effective in fog and haze as it is in bright sunlight. From Hobie, 800-554-4335; Smith, 208-726-4477; and Serengeti, 800-525-4001.

The Nikon GX lens in the Avalanche nylon frame ($145) combines a copper-color tint with a double-gradient mirror coating–dark bands on top and bottom to tone down sunlight from above and glare from below–with a polarizing filter. It works great, cutting glare with the best glasses–or, for that matter, window shades. From Nikon, 800-645-6679.