The Sun Worshipper’s Guide to Visual Light Transmission (VLT)
Sunglasses Guide

The Sun Worshipper’s Guide to Visual Light Transmission (VLT)

The more you know about your gear, the better equipped you are to fully enjoy your time outside. At Sunski, we’re all about basking more and stressing less, and that can only be enhanced by the right kind of eye protection.

That’s why we want to talk about visual light transmission (VLT) in sunglasses, and how it can magnify your adventure time. By the end of this article, you’ll be an expert on VLT, able to pick the perfect sunnies for every outing. So let’s get to it!

What is VLT?

VLT refers to the percentage of light that reaches your eyes through your lenses. In short, lenses with a high VLT allow more light to reach your eyes, while low VLT lenses keep more light out of your eyes.

Most of this comes down to lens color. Darker colored lenses are better at blocking light. Lighter lenses–yep, you guessed it–allow more light in.

Woman in winter gear wearing alpine sunglasses

Alpine sunglasses like the Tera are the shades of all trades, fit for snowy or earthy conditions

You may be wondering if VLT really matters. You’re heading outside, shouldn’t you go for the lowest VLT for maximum protection? Not always.

Why should you care about VLT, anyway?

If you’re here, you must crave time outside like we do. When you’re out chasing the sun and the stoke, the color of your lens has the power to actually impact your experience.

Imagine you’re out climbing in Joshua Tree, or trekking around the rim of the Grand Canyon. Odds are, in these desert places, you’re extremely exposed to the sun. The sun’s brightness can be seriously piercing. You want to be ogling at the epic landscape, but you’re squinting even with your sunglasses on. That’s a problem! Your sunglasses may have too high of a VLT for the conditions, meaning your lenses are too light.

Dipsea sunglasses held up to a blue sky

Sunglasses like the Dipsea Champagne Brown have an Amber tint and a higher VLT. Can you tell this lens allows more light in?

On the flipside, what about cloudy days? You know, when you head outside, and you’re constantly pulling your sunglasses off and back on. It’s too bright without your shades, but with them on, it’s too dark. In this case, your sunglasses most likely have too low of a VLT. Dark lenses on cloudy days are not your friend–at least, not if you want a clear line of sight.

The long and short of it is that the VLT of your sunnies can change the way you see the world. The Sunski philosophy is built on heading out into nature and living your life outside. It’s how we find peace and joy in this busy world. And basking in all the glory is all the more enhanced with the right VLT sunglasses.

Man basking in the sun on the beach with lo light Sunski sunglasses on

Scope the Sunski Lo-Light Collection! These sunnies perfect for cloudy adventures, but they also add a cool and funky flare to bright beach days

VLT for Extreme Adventures

Picking the perfect VLT is especially important for the full-send adventurer. The wrong VLT can limit contrast in your line of sight, and with sports that require precision, that can be dangerous. When you’re shooting down a single-track, it’s essential that you have your depth perception. Otherwise, you could hit a snag and take a nasty spill.

Ramble with Optimal VLT

Sunski’s Ramble Collection was specifically designed for every kind of cycling adventure. In this line, you’ll find a wide range of VLT in the sunglasses. For instance, the Foxtrot, Anza, Velo all have multiple lens color options.

The Foxtrot even has Green and Amber Photochromic styles, meaning the lenses darken and lighten based on the amount of sun in the air. Perfect for those partially cloudy days! These shades are high-performing sport sunglasses, but they won’t make you look like an action figure. Aviator in shape, the Foxtrot never goes out of style.

Close up of a man's sunglasses as he looks into the sun

Shop Now for Type-1 Fun Sling

For cycling, sunglasses with the right VLT are of the utmost importance. You need to be able to see details, like the contours of the earth and the depth of the track. Understanding VLT can ensure you pick the best gear for your ride, so you stay safe and confident on the trail.

Alpine with VLT in Mind

In the same vein, alpine sports are often made more challenging by glare that comes at you from all angles. Unfortunately, a lot of the alpine eye protection out there isn’t up to our standard of protection and style. This challenge helped spur the Sunski Alpine Collection, a line of high-quality, fog-free sunglasses that don’t compromise on looks. Our Alpine silhouettes will keep you feeling good and savoring the days outside like never before.

Three pairs of alpine sunglasses held up against a snowy mountain background

Most of the Alpine Collection has a low VLT. Hitching up to altitude, above treeline, you’re likely exposed to light whether it’s sunny or not--especially if there’s snow. Full coverage is almost always a must at elevation. That’s why all our alpine sunnies come with detachable side shields, so you can block out the glare and focus on the adventure instead. The award-winning Treeline comes with four different lens colors, too, from as dark as Slate to as light as Amber, so you can find a pair that suits your personal style and VLT needs.

VLT and Lens Color

No matter where you’re headed, there’s a chance of sun or shade. Even the scorching desert isn’t immune to cloudy days. So how can you make sure your lenses are the right VLT for your adventures?

Stock up on a variety of lens colors! We make Sunskis to suit every kind of outdoor enthusiast, so whether your style is sunny lounging or overcast hiking, we got you covered with the best adventure sunglasses around. Plus, keeping a few different lens colors on hand means you’ll always have a palette to match your mood!

Blue, orange, and pink sunglasses laid out in the sand

Shop Now for Type-1 Fun Sling

Here’s a quick guide to Sunski lens colors and VLTs, so you can find a pair (or two) to suit your needs.

High VLT: Best for Cloudy Days

Sunglasses with high VLT allow the most light to pass through, which is mostly needed on cloudy days. If you’re not sure what to grab on a gray day, aim for light colored lenses. At Sunski, many of our highest VLT sunglasses are in the Amber variety, like the Tortoise Amber Yuba. Amber-tinted lenses are a trendy, functional option for those sorta bright days. If you go much darker, you’ll lose some definition in the view. When you’re hitting the trail for a hike with an epic vantage point, you want to savor the details, not wash them out! So go for a lighter-colored lens.

Sometimes, the days feel too dark even for Amber lenses. Whether sunglasses are your style must-have or your eyes are particularly sensitive to light, we’ve got you covered. Our Lo Light Collection has the highest VLT of all the Sunskis, so you can wear them with ease on the gloomiest of days. An added bonus? This groovy collection adds a fun zing of color to your adventures. See the world through a new lens of color with the Copper Rose Velo or the Black Arctic Shoreline.

Lo light Sunski sunglasses resting on a volleyball at the beach

Low VLT: Best for Bright Days

To keep your peepers protected on the intensely sunny days, you definitely want a pair of low VLT sunglasses. Since they don’t let in as much light, your eyes can stay mostly shielded from the brightness. The darker the lens, the lower the VLT and the better the eye protection. For Sunski, that typically means Slate- and Forest-colored lenses.

Life outside is so precious, and you don’t want your limiting factor to be sunburned eyes. With low VLT, dark lenses, you can embrace the full bask and maximize your time in nature. Soak up the rays and lap up the rad views with the perfect pair of supportive sunnies.

Man hitting the slopes clad in dark alpine sunglasses

Hit the slopes in the Black Forest Couloir: stylish protection for ultra-reflective conditions

The Exception: Under some circumstances, low VLT lenses may be the right choice on cloudy days, too. If you’re heading into the alpine terrain, you’ll be so exposed to the elements that low VLT sunglasses are the move. Standing on a snowy slope, it doesn’t matter if there are clouds. You’ll feel the sting of the glare from all angles. So grab a pair of Alpine Sunglasses like the Treeline or the Couloir for optimal coverage.

Sunglasses for All Conditions

In all, the soundproof method for keeping your eyes protected is to nab a few pairs of sunglasses with a variety of VLT. This way, you’re prepared for any kind of adventure, and you’ll keep that view crystal clear without the squinting.

You don't have to totally fend for yourself when shopping for sunglasses, though. Check out our rundown of types of sunglasses to find your perfect match.

Guy and girl sitting back to back on a tennis court with colorful sunglasses on

Nab the right sunglasses to keep precision in your vision 😎

Mix and match your sunnies! Grab a Lo Light and a Slate lens to keep a light and dark option on hand. Or go for Amber and Forest lenses.

If all this VLT talk has piqued your interest in lenses, check out our deep dive into lens colors, where we explore how to choose color.

Meet the Author

madison author bio

Along with writing blogs for Sunski, Madison creates nature books for kids. She grew up with BLM land in her backyard, which fueled her affinity for adventure and epic stories. In her spare time, she enjoys swimming, camping, and reading under the sun.