It’s pretty hard to overstate the coolness factor of sunglasses – just picture Brad Pitt or Jennifer Lopez, and you can instantly visualize them with their super cool sunglasses. Metal frames, plastic frames, aviator or huge oversize frames, they all convey a sense of style, and project a certain persona.
And then there are the tinted lenses – purple, grey, yellow, brown, red, green, mirrored – practically every color of the rainbow! But however great sunglasses look, no matter what image they project, they are supposed to perform some basic functions – protect your eyes from brightness, from the harmful effects of ultra-violet (UV) light, and from blinding glare. So while the hip factor is great, the real question you need to ask is “Are these lenses doing the job I need them to do?”
Let’s touch very quickly on the nature of light. You probably recall from science classes that “white” light is actually made up of every color of the spectrum – good old Roy G. Biv (red, orange, yellow, green, blue, indigo and violet). Our eyes are designed to most effectively process “white” light. The intensity of light can vary, from the absence of light (black) to blinding (such as a welders arc). Sunglass tints are designed to reduce the brightness of visible light to comfortable levels, and (ideally) stop 100% of damaging UV light rays.
However, the tint, or color, of the lenses impacts the quality and comfort of your vision as well. Every tint color stops certain colors of the spectrum, while letting other colors through; sometimes that is desirable, and sometimes there are unintended consequences. Here is a brief rundown of a few of the pluses and minuses of particular colors.
GREY: This is essentially a neutral filter, so the color values of objects you are looking at remain very close to their natural color as seen by the naked eye. Best for people who are sensitive to color shifts, require true color rendition, or who are consistently in very bright light. Not good with variable light conditions, or when extra definition is required. On plastic lenses, grey may fade to a reddish-purple over time.
G-15: This is a mixture of grey and green, developed by Ray-Ban to provide better vision for pilots in WWII. This color will not fade like grey, and feels “cooler” to the eyes in very bright light. Otherwise, very similar to GREY.
BROWN: Brown tints absorb more blue light and pass more red light than grey or G-15. Generally speaking, our eyes have more difficulty processing blue light; by reducing it, our eyes are forced to focus more on the yellow-green portion of the spectrum. This results in enhanced contrast between foreground and background objects, and is also helpful when there is an excess of blue light – on the water, in rain or road-spray conditions, even on snow. Makes the world look a bit warmer and brighter. A small but significant percentage of the population is very negatively sensitive to this color.
BLUE: This is a very cool looking color in sunglasses, but is totally counter-productive. This will actually make it more difficult to see in many lighting situations, and produce more brightness and glare.
YELLOW: Very popular among skeet shooters and the senior set, this tint actually makes the world look brighter. The yellow tint makes the skeet target pop against the blue sky, enhancing performance. For seniors, natural aging of the eyes lens makes it less clear, and possibly a slight brownish color (brunescence). The yellow tint removes much of the blue light, and concentrates the yellow light, which makes the world appear brighter again. Some also report the tint helps prevent blinding glare at night from the new super-bright blue headlights.
RED: Red will stop 100% of blue light. I have seen very deep reds with mirror coatings used for people who spent hours and hours on snow, or at sea, where the amount of blue light can be very intense. This color will provide not only relief from the blinding glare of blue light, but also good contrast – think easily spotting moguls on a ski hill. The downside is that red tints should NEVER be worn while driving, as it is very easy to confuse red and green traffic lights.
So which tint is right for you? Hopefully after reading about the pros and cons of various lens colors, you know now what shade to look for in your new sunglasses. Still confused? More questions? Just leave a comment, and I’ll do what I can to give you more information.
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