VLT Range, Polarized, Contrast, Mirroring, Rims, Retainers

What is VLT Range?

VLT range is a numerical expression of photochromism. Lower lows get darker in bright light. Higher highs get clearer in dim light. For example, 12-87% is a better VLT range than 14-64% because it gets both darker and clearer. The 12-87% lens allows only 12% of light through in bright conditions, and allows 87% of light through in dim conditions. As a baseline, aim for a VLT ranges of ≤15% – ≥60%.

How to choose VLT range

All photochromic lenses offer a visible light transmission (VLT) range, unlike non-photochromics which have a static VLT rate. Many Tifosi lenses, go from 14-64%, which illustrates a good baseline. The low end of the range for most brands is between 10-15%, and the high end is typically 60-90%. Any photochromic lenses that land in those sweet spots are generally going to be versatile and effective at all times. Be wary of choosing models that go above 15% on the low end of the range, and below 60% on the high end of the range; they may not be light or dark enough for all day wear.

For use in extra bright environments, like the High Sierra on for snow travel, we recommend low ends closer to 10%. For use in lower light, such as in forests, or if you’ll be adventuring in twilight, choose a lens with a high end ≥80%. You can spend more money to get lenses with wider ranges. Lenses in Julbo’s reactive series cost significantly more than Tifosis, but offer best-in-class VLT ranges, 12-87% at time of publication. They are darker than average in bright conditions, and clearer than average in dark conditions.  

The pros and cons of polarized lenses

There’s a common understanding that polarized lenses are superior to non-polarized lenses, but most of the time this is not actually true. As everyone knows, they do reduce glare and can be absolutely essential on the water – we do recommend them for kayaking, canoeing, stand up paddle boarding, fishing, etc. However, they also hinder depth perception, remove visual information (a bit of glare can be useful), and mess up digital screen viewing such as looking at your iPhone GPS app. For most use cases, the cons outweigh the pros, thereby making polarized lenses a net negative. Don’t choose polarized lenses unless you’re on the water!

Why we prefer rimless or semi-rimmed photochromic shield sunglasses

While there are advantages and disadvantages to having more or less rim (the material encasing the perimeter of the lens), we generally recommend semi-rimmed or rimless shield sunglasses. The disadvantage of any amount of rim is that it hinders peripheral vision slightly by creating blurry distortions as you shift your eyes all of the way left, right, up, or down. Furthermore additional rim material adds a few grams of weight, and creates a rigidity to the frame that makes the arms press harder into the side of your head and feel less comfortable. Rimless designs are lighter weight and flex at the bridge, creating a secure fit that is easier to hold with less pressure from the arms. They adapt better to your head shape.

On the other hand, more rim coverage on the perimeter of the shield lens decreases snap-in-half potential, and adds a bit of extra scratch protection around the edges. But if you’re careful with your gear and rarely ever damage it, rimless shield sunglasses will offer superior performance. It’s worth noting that a majority of sunglasses fail by virtue of being lost, rather than broken, which means the durability boost of additional rim doesn’t actually prevent the primary fail case. A happy medium for most folks is to choose a pair with rim on top, but without rim on the sides and bottom.

The pros and cons of color/contrast enhancing lenses

Color enhancing lens tints can be a legitimate performance add-on. At the same time, they are also an overhyped product marketing ploy and don’t do as much in the real world as brands make it seem. They are at their best in low contrast environments like cloudy snowscapes, and for speed sports where spotting any obstacle in your path as quickly as possible is important. Smith ChromaPop lenses give deeper saturation of green and warm colors, adding visual information and improving field of view. But the difference between color enhancing and non-color-enhancing is smaller than you might think. Anyone trying to save a buck should not pay hundreds more to access this technology, but we definitely recommend it for skiers.

Pros & cons of mirrored lenses

Two-way mirrored lenses reflect light, offering a non-polarized, non-tinting way to block glare and additional brightness. As such, they are popular and recommended for snow and water sports. They also look really cool and give you privacy – nobody can tell where your eyes are looking. But there are drawbacks! A pair of $250 Julbo Ultimates that I tested performed very poorly because the gold mirroring was so aggressive that it frequently reflected a gold shimmer into my field of vision. The mirror wasn’t necessary for the hiking conditions, and the effect was so annoying that now I basically never wear them. Additional darkening can be achieved without mirror, and many photochromic lenses do this. Clear-to-smoke colored lenses without any, or much, mirror often have the widest VLT range in any brand’s given offering. Like the ROKA Matador Air, for example. Another downside is that mirrored coatings also scrape off easily.

Why use sunglasses retainers

Having the toughest frames with the most shatter-resistant lenses in the world won’t help against sunglasses’ primary fail case – becoming lost. Sunglasses have a long and storied history of falling off heads, into the water, or otherwise being forgotten. For every pair of sunglasses that reaches end of life via scratching, cracking, or breaking, ten pairs will simply go missing. That’s why we recommend retainers, like Croakies, to help prevent the primary fail case of sunglasses – being lost. Focusing on not losing your sunglasses is a better way to prolong their life than focusing on more durable frames and rims!