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Sunglasses: Revo Redpoint
For sunglasses, I stick with glass lenses with high quality anti-reflective coatings, for example, brands like Revo sunglasses.
Except that on a bicycle, there is the danger of an impact shattering even shatter resistant glass lenses (e.g., a chunk of gravel at 40 mph), making the choice of polycarbonate or similar materials a smart move for biking.
Revo has traditionally produced very high quality lenses in their sunglasses, but I’ve always used Revo sunglasses with glass lenses. So how does the new Serilium polarized lens fare?
The Revo Redpoint @AMAZON sunglasses use the Revo Serilium polarized lens. It’s a very high quality polycarbonate lens that I’m satisfied with, unlike the Oakley lenses, which show a double image (I tested both under the same conditions).
I’m very sensitive to these things as a photographer, and you might not be. But any sunglass that creates a double image degrades optical quality, and could lead to eye fatigue over time. I see no reason (other than price) to purchase an inferior lens.
The Revo lenses have both an anti-reflection coating on the internal side of the lens, as well as a hydrophobic coating. I found that with my full-finger gloves I could wipe away any lingering small droplets of rain, though most rolled off naturally.
Fogging is minor, and clears up almost instantly with a little air movement.
The Revo lenses are apparently not oleophobic (fat averse), so smudges from body grease, sunblock, etc do stick to the lens, and they must be cleaned.
Discerning details in shadow
While riding in mixed cover so that trees throw strong shadows on an otherwise sunlit road, the 13% transmission of the Revo Redpoint bronze lens makes it a challenge at speeds over 15mph to discern sticks or cracks in the roads.
Testing the Redpoint with a 17% transmission Cobalt len, I do perceive some improvement in my ability to discern details in darker area under mixed sun/shade conditions. I also like the more natural color rendition of the Cobalt lens, and it produces a bluer-blue sky than the bronze lens. But the bronze lens is preferable on overcast days.
I am in my mid-40s, and thus those with younger eyes (wider pupil diameter) can quite literally see a much brighter image, and might not have this issue. Those with older eyes will have it worse: as we age, the maximum pupil diameter drops from about 8-9 millimeters to 5-6 mm by age 50 or so. That’s a 3X reduction in the amount of light admitted into the eye (9mm vs 5mm).
Ultimately, one has to choose based on riding conditions. With very bright conditions, a darker sunglass is a plus, but in mixed lighting, a less dark lens is better. For racing, I’d choose a lens that allows adequate brightness in the darkest areas, and this might rule out polarized lenses entirely.