This is a question I get asked by a lot of people. They usually mean "If I only had one pair of sunglasses, which one should I get?" but that's a discussion for another post.
This post is about how to choose the perfect sunglasses for the conditions and mood that you are in. Assume you have every lens option from any brand at your disposal. All colors and technologies are available.
Understanding this can take some time, but when you master it any day and all conditions will be yours to enhance and enjoy, and you will always want to be outside, whether in full sun or cloudy, hot or cold, arctic or tropical.
This is the full-length, everything you want to know post. There will be an abridged version published as well.
In This Article
Lenses or frames first?
Determining What The Perfect View For You Is
Understanding the Science of Sunglass Lenses
Putting it all together
Lenses or frames first?
Considering Optics and Style
The way we do it here is to pick the lens we want first and then pick the frame from the available options. This makes the choice much easier as each lens only has a limited number of frames that goes with it, though usually there are enough styles to find one that works for you. If you only care about style and not optics, you wouldn't be reading this. Here we care about both. Without discounting how important style and looks are, especially one that makes you look better, we cannot forget that the main point of sunglasses is the lens.
Of course, everyone is different and everyone's preferences will not match up in all scenarios, but we can discuss general guidelines and principles that will help you make the perfect choice.
Determining What The Perfect View For You Is
Here's what we want to do in one line.
We need to figure out what it's like outside, if you want more or less of certain colors, and which lens will do that best.
There are five factors we need to determine.
What are the dominant and secondary colors of your environment?
Every place we go has features and colors that stand out and dominate the view more than others. It is important to have a general understanding of what these are if we want to either boost or mute them, to achieve the views we really want.
On a downtown street, the buildings are often grey, black, brown, tan, or white, the street is usually grey, black, or white, and then you might get some greenery from a tree or garden or some bright red from signs or décor. The cars are also many different colors. This will vary from place to place, as a street in New York looks different from a street in Prague.
In the country, depending on where you are, you might get a ton of green with trees and grass unobstructed by any buildings. Other places where it is very hot year-round often have redder and yellower features when there are less vibrant green sources.
When you know what the surroundings are you can decide what you want to do with them. Do you want to keep the world bright and alive or cool it down a bit? Do you want more contrast or more warmth?
The general principle is that by boosting the dominant color relative to the others the view will be brighter (in color, this does not mean the lens will let too much light in). For example, by boosting the green relative to other colors the trees and grass will be a brighter color, with the saturation and luminance enhanced.
Muting the dominant color relative to the others will bring out details in the view that would have been harder to spot otherwise, and contrast is enhanced. For example, muting green on a golf course will bring out the different shades in the grass and trees, make it easier to spot the ball, and increase depth perception.
What is the color temperature of light?
This one is a bit more complicated, but we will go through it as simply as we can, though in another post we can get more technical. Believe me, I probably enjoy physics less than you but getting a basic understanding of color temperature really helps with lens choice.
In short, instead of looking at the color of the objects around you like in step 1, we are looking at the color of the light itself.
We all know the color of the light is very different at sunrise, sunset, midday, in cloudy conditions, etc. How those differences relate to the tint of all colors we see is very important.
If you shine a green light on something, the color of that object will change. It is the same with the sky, only less drastic than a green light. The color of the sky goes from warm to cool and the effect on the color veneer of the world is the same. Everything will look more orange in a very brilliant sunset. In some conditions, even a grey lens will slightly change the color temperature a bit cooler.
See the difference between the light at midday and sunset and how it affects all the colors in the scene.
The principles here are to understand the color temperature and either change it to a warmer or cooler tint or accept it as is. This is the exact same as a photographer adjusting white balance.
This is related to, but not the same as step 1. Here we are altering the overall feeling of the brightness rather than aiming to colorize our environment. Some brown lenses in the late afternoon, while the sun is still bright and high, can make it feel like an early onset of sunset, which you may like or not want. Some green lenses in the morning when facing away from the light can create a cooling effect that almost makes it feel overcast.
This is also why our brains need some time, usually around a minute, to adjust to wearing lenses that significantly change the color temperature and the white balance, like brown or rose lenses. Our brains need to find the whites, readjust them, and then adjust all the other colors relative to the white benchmark.
It is these kinds of adjustments we can keep in mind when thinking about color temperature.
What are the weather conditions around you?
This category mainly relates to cloudy vs. sunny weather conditions, as if it's too dark because of the weather, like heavy rain, you won’t need sunglasses. It also heavily relates to step 2 because the conditions in the sky will be the determining factor for what color the light is.
If it’s sunny there is a lot of light in the sky and we generally want to use a darker lens because we often can barely function without sunglasses. A lens that is too light will let too much light in and, depending on the tint, can boost already bright colors to an unseemly warmth.
When it’s cloudy there are many more variables. The amount of light is often enough to make us squint but still be able to function normally. The light is also not the same color profile as the full sun, since the sky is white instead of blue. Without getting into the details here, this increases blue light in our view relative to other colors and creates a cooling and dulling effect that mutes nearly all colors relative to what they would be in the sun and reduces both color and contrast.
In sunny conditions, any dark lens or any color can work, but some may be too “hot” to be comfortable. In cloudy conditions, many lenses may be too dark or too “cool” for the already darker and cool view, and we will want to both brighten and add contrast while using a lens that isn’t too dark.
What activities are you engaging in?
Up until now, we have been trying to understand the factors we need to achieve the best and most beautiful view. However, when the decision involves a specific activity, that often becomes the overriding concern at the expense of the beauty the rest of the view can provide.
I don’t really care about how the world looks when I am playing tennis. I just want to see the ball and court better.
Sometimes we want both, to have both a wonderful view and high functionality for our activity, like driving or going to the beach.
We also want to consider lens material here, as any activity that can involve impact to the face or a fall is prohibitive for glass lenses, which can shatter. A lens material like Trivex or polycarbonate will be a better choice in that situation.
There are no scientific principles involved here. This is about balancing priorities.
What mood are you in and how do you want your optical experience to look like?
Finally, we can use color to affect our mood. According to color psychology, different color temperatures evoke different feelings. For example, warm colors are said to bring to mind coziness and energy, while cool colors are associated with serenity and isolation.
I would argue that this category is usually already taken care of because we generally want to be happy, and getting the most beautiful possible view will usually do that to the degree that color psychology can play a role.
This category is for those times you really need to boost your energy, or you just want to calm things down and not have to focus much on the world around you.
The principles here are to use warm tints to brighten and energize you and use cooler tints to feel calmer. However, this can vary a lot depending on several factors which will be discussed in a separate post.
Understanding the Science of Sunglass Lenses
Lens Selection Principles
To know how to use sunglasses to get the perfect view we need to understand how they work. Don’t worry, we aren’t getting to physics of how they actually block and reflect light photons. We are just going to deal with how they affect color.
Here there are two tools that we will use, and the relationship between them is the key to using sunglasses like an artist or photographer.
The first is the visible light spectrum.
Here it is with the colors more pronounced.
Light is a form of energy that travels in electromagnetic waves. We can see the wavelengths of light from around 400nm to 700nm. The lower the number, the shorter the wavelength and the higher the energy. You can see that the different frequencies make up certain colors, like blue, green, yellow, red. Violet is there but it isn’t really visible.
These frequencies come from different light sources, most notably the sun, but also from artificial light like lamps. They leave the light source as waves of energy and bounce off different objects until they hit our eyes.
Different objects absorb different frequencies of light and reflect others. When red and green light are absorbed, but blue light is not, the only light bouncing off the object into our eyes is blue. So, we see blue even though that’s the only color that object does not accept.
Are red roses really red? No. We see the red light being reflected from them and interpret that as them being red.
Our eyes have color receptors called cones. Cones are a type of photoreceptor cell in the retina. They give us our color vision when they are stimulated by light hitting them. The retina has approximately 6 million cones.
There are only three types of cones as far as color is concerned. Blue, green, and red receptors. Those are the only colors our eyes can actually see. They make up the RGB structure used in screens, cameras, and light bulbs, as no other color is picked up the same way as these three. Our eyes cannot pick up yellow light.
Because we can only see these three colors, and all colors we see are combinations of them, we can use the principles of color theory to mix and match light. Light is on a linear spectrum, but color isn't. Enter the second tool: The Color Wheel and Color Theory.
We need to use the color wheel to understand how each color lens will affect other colors.
In color theory, the term "complementary" refers to two colors positioned on opposite ends of the color wheel. Pairing complementary colors, like in fashion or art, creates a striking and impactful color combination, as the stark contrast between the two colors makes them appear brighter and more prominent when used together.
For our purposes, the color wheel and complementary colors will help us understand which colors are being boosted or dimmed, and how that affects other colors.
We also need to keep in mind that colors that neighbor each other on the color wheel are more similar to each other than complimentary colors. Blue and Green will be more similar than Blue and Red.
Our brains use color theory to help understand the mixes of wavelength information it is receiving from each object, and that’s how we can see so many different colors even though we can only physically see Red, Green, and Blue. In other words, our biology interprets physics in its own way.
It uses psychology as well, which we will touch on soon, and that is why there are color-blind people, why I might see or enjoy a view differently than you, and why some colors make us happier or more excited.
This now leads to the following six principles of using the light spectrum and the color wheel to understand how sunglasses affect light.
Sunglasses transmit some light that passes through the lens, they absorb some light into the lens (as heat which then cools off), and they reflect some light away from the lens which is why the sunglass lens might have a mirror effect even without an actual mirror coating. How the lens differs in doing these three actions is the entirety of any differences between lens colors and technologies.
1) The color of the lens will let more of the same color light through relative to other colors. A green lens lets more green light in, and a rose lens lets in more red and blue (what combine to make rose).
2) The color opposite the lens color on the color wheel (the complementary color) will generally be the least transmitted and most muted. A green lens will most block purple (a mix of blue and red), a brown lens (which is shades of orange or red) will block blue, etc.
3) The color of any mirror, with some exceptions, will block the same color as the mirror and create an opposite effect. A blue mirror will block blue light and make a grey lens more orange or amber. Another color lens with a blue mirror will make the tint lean towards amber from wherever it is on the wheel (a green lens with a blue mirror would become more yellow). I will discuss this more in another post about mirrors.
4) Letting relatively more light of a color through the lens brightens that color relative to other colors. Letting less of that light in relative to other colors will make other colors brighter relative to that color.
5) Generally speaking, if you want more contrast (difference in colors) you will use a lens that blocks the most prevalent color and boosts the other colors. If you want less contrast you will use the lens that is the same as the dominant color in your environment.
6) Lens colors can have a profound impact on our mood depending on where the tint falls on the color wheel.
This is because the color wheel can be divided into warm and cool colors. The warmth or coolness of a color is also known as its color temperature. The color combinations found on a color wheel often have a balance of warm and cool colors. According to color psychology, different color temperatures evoke different feelings. For example, warm colors are said to bring to mind coziness and energy, while cool colors are associated with serenity and isolation.
Warm colors are the colors from red through to yellow. These colors are said to bring to mind warmth, like the sun.
Cool colors are the colors from blue to green and purple. These colors are said to bring to mind coolness, like water.
Lens colors and effects principles
We will now apply the principles above to the five main lens colors. Each of these will be discussed in much greater detail in their own dedicated posts.
We will avoid getting into mirrored lenses for now, though we will have many posts on them. The reason is that in regard to the ultimate tint of the lens, mirrors are like seasoning and the base tint is like the actual dish served. They can have a noticeable effect, but they cannot fundamentally change the color of the lens.
We will also leave polarized lenses to their own separate post. In general, I recommend them.
- Grey Lenses:
Grey, or black, is not a color. It absorbs all colors (roughly) equally. A grey lens will be the densest and darkest lens option. Since it is not a color, without any added lens technology it cannot boost or dim any color relative to others.
In terms of color temperature, without any added color-boosting technology, grey lenses can feel like the lights have been dimmed and may cause a very sight colder feeling, which can be good or bad depending on the situation.
Grey lenses will work in pretty much any environment since they will not alter the color profile either too much or too little, though in low contrast environments like overcast conditions grey lenses may be undesirable as they dim the available light, further reducing contrast. They can therefore be fairly boring and plain, not really adding much life to the view, especially on cloudy days.
It is also not on the warm or cool side of the color wheel, so it is relatively neutral in how it affects our mood, though that is only in regards to the effect of the tint.
I only wear grey lenses on full sun days, when I just want a neutral, classic view and the environment already has plenty of color and warmth.
- Brown Lenses:
Brown lenses are usually made up with a combination of red and green, but mostly red. There are many hues of brown, some yellower and some redder, so some lenses with "brown" lenses can be very different from each other, but we will generalize here. Brown is close to grey in terms of how dark the lens will get, but not how it feels.
Since it is composed of red and green, but not blue, it blocks blue light more than any other lens (and many brands add blue blocking technology on top of that). Brown is on the "warm" part of the color wheel and boosts colors to be “hotter”, more exciting, and more alive.
Brown lenses add a lot of contrast, as is explained here, and are great for sports as much as for everyday wear like driving.
Brown lenses change the color temperature to a warmer shade (cooler kelvin), and can sometimes make it feel like the sunset is approaching when it is still hours away.
I wear brown lenses over 70% of the time where I live, often changing the type of brown based on the conditions, which you can get a feel for over time or read each brown lens review we publish to get a better idea. If it's cloudy, I will almost always wear brown except for the occasional rose lens. The only times I do not want brown lenses are in a very red environment like the desert, or when it is super hot and colorful and brown is just too "hot" for me and I want to cool things off. That is my personal preference and is the same for most people I have met, but I know people who prefer brown even for the hottest, reddest places.
- Green Lenses:
Green lenses are one of the only lenses, along with blue, that are actually based on a color on the light spectrum. This makes them a bit simpler, though there are still differences between different shades of green lenses, some lean more towards blue and some more yellow.
Green lenses will boost anything green, which can be very pleasing on sunny days with a lot of grass and trees. They also transmit relatively less red and blue (which together make purple, which doesn't exist). This means they can be used as a contrast enhancer in very red and blue environments, like the desert or the beach, but definitely not the golf course on a sunny day.
Green is on the "cool" side of the color wheel and can contribute to a calmer, more tranquil feeling. It can also be very dull in cloudy or snowy conditions, as it changes the color temperature to feel a bit cooler (higher kelvin).
You won't find many sports lenses with green lenses, not because green is terrible or worse than grey, but because brown or rose lenses are much better for that purpose.
I exclusively wear green lenses in full sun when surrounded by lots of green I want to enhance, or when I go to a hot and red environment.
Randolph AGX/Cobalt Lens
- Rose Lenses:
Rose lenses are the most interesting lens tint and I highly recommend checking out our post going in depth on the topic.
In short, they boost blue and red, while dimming green. Since we are most sensitive to green, a rose lens will essentially enhance color perception across the board, but reds will still be most impacted. This means they will be particularly contrast-enhancing in green environments like golf courses and forested areas.
Like brown, rose lenses might be too "red" for dry, red environments, but unlike red, rose lenses are not squarely on the "hot" side of the color wheel, instead bordering both sides. This means rose lenses can be a perfect mix of hot/cool, but still be color-boosting and contrast-enhancing for all colors, with green still bright enough. The color temperature is still changed to a warmer feeling shade (lower kelvin).
I will wear rose lenses in any condition when I'm in the mood, and I wear them for sports most of the time. All of Oakley's Prizm Sport lenses are rose-based.
When you first put them on the experience can be intense but after around 60 seconds your brain adjusts and it's like a very high-contrast grey lens. Because of this, it can be difficult to show a real representation of what a rose lens looks like, but here's a decent one.
- Blue Lenses:
You will rarely see blue being worn other than fashion tints. A few brands like Persol and Vuarnet make them, but their utility is limited, though they look great aesthetically.
They are essentially the opposite of brown lenses. Blues are boosted and reds and greens are muted, pretty much exactly what you do not want normally. Boosting blue light is usually considered to be bad, but it creates a really nice crisp, vivid visual, particularly when the light is very orange, as it changes the color temperature to a cooler feeling (higher kelvin).
Where they work well is in very red/orange places. It is definitely on the cool side. They are not great for acuity or contrast in shadow and could cause eye fatigue in bright sun.
Lens Materials and Curve Principles
Lenses can be made of different materials and they can significantly change the optics and functionality of the sunglasses.
Glass lenses are the best for optics in terms of clarity and color distortion. Most people who have glass lenses will only not wear them when they are worried about damaging them, like for sports. They really are that good.
Other materials are still very good optically, though not as good as glass, but they are much lighter weight, impact-resistant, cheaper, and easier to put prescriptions in.
Any activity that can involve impact to the face or a fall is prohibitive for glass lenses, which can shatter. A lens material like Trivex or polycarbonate will be a better choice in that situation.
Lenses also come in different curve values that can significantly affect coverage and prescription availability. Basically, a lower number base curve will be more flat, and a higher number base curve will wrap around your head more.
Here are some diagrams that illustrate the common base curves:
A higher base curve is going to do a much better job wrapping around your face, fitting closer to your eyes. From a performance standpoint, it will do a better job blocking out peripheral light leakage and wind.
Light leakage can cause several issues:
Direct sunlight (depending on the angle of the sun), reflected glare, or bright ambient light can come through from the perimeter gap and hit you in the eyes.
Bright light or direct sun coming from behind can reflect off the inner surface of the lens. This often appears as curved lines of light seen on lenses and can be distracting.
Direct sun from above or the sides can illuminate your face, causing you to see a reflection of your face or eye on the inside of the lens. Anti-reflective coatings help here but do not completely solve the problem.
These issues can range from annoying to blinding, depending on the conditions, how sensitive your eyes are, and the activity. Sometimes it is just fatiguing, like on a long drive back from a day of skiing, when your eyes are already tired.
In summary, a lower (4 or 6) base curve will be more fashionable and look better, and be a easier to RX. An 8 base will probably perform better (with little or no RX correction) in most sports or demanding situations. Base 6 sunglasses are sort of a good compromise.
Lens Technology Principles
When it comes to what technologies brands use to enhance the colors, contrast, and clarity, there are only really a few principles involved, in theory. In practice, some brands’ application and manufacturing sets them apart from others and makes some worth the money and others not.
In terms of how to manipulate the lens to enhance the colors and contrast, the issue that all brands are solving is this: Normally, the eye's retina has trouble perceiving the difference between blue and green, and red and green light. You’ll remember these two pairs are next to each other on the light spectrum. The light we get that corresponds to the light in between these colors confuses our brain a bit and muddies the colors. This is the cyan and yellow light that separates blue and green, and red and green.
By blocking those light wavelengths, an advanced lens can essentially boost the colors we really want to see (red green, and blue) and allow our eyes and brains to interpret the combinations of them much more purely and richly.
In addition, High Energy Visible Light, or HEV light, is also filtered out. This is the far left end of the visible light spectrum where the blue light has the highest amount of energy. Short-wave high-energy blue light creates scatter and haze, making objects appear somewhat blurry. HEV-blocking properties, which reduce haze and blur, provide greater clarity of vision and enhanced color definition, besides health benefits, as HEV light may contribute to macular degeneration and/or loss of vision detail.
Different brands accomplish these effects through different techniques and materials, and some are definitely better than others. They all talk about this on their websites and in their patents. We will go in-depth on each brand in other posts.
There are also other lens technologies like photochromic lenses. These lenses lighten or darken in response to sunlight's intensity using the UV rays from the sun. This will be covered in a separate post.
Lens materials make a significant difference in weight, clarity, scratch resistance, and impact resistance, as we will discuss in further detail in other posts.
Putting it all together
How to make your decision
Now we are at the point where we have all the science and the knowledge. How do we make the right choice for the perfect lens?
The way I find it works for me is by trial and error. You will need to try them out to get a feel for each lens, where it works great, and how versatile it is. There are nearly infinite outdoor conditions, with different skies, lighting, scenery, activities, infrastructure, etc. All of them will be better with a specific lens, the same way nearly every photograph you see has been altered in post-production in some way.
I am constantly tinkering and discovering new applications in different conditions for each lens I own.
Discussing the what and how of different lenses from premium brands, their effects on the view, and when it is best to use them, is the goal of this website.
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