Where to Start
Lenses have a pretty amazing amount of technology available to choose from. You’ve got color (tint), shade (darkness), filters (Blue light, UVA, UVB, Polarization, etc.), coatings (Scratch resistance, Anti-reflection, etc.), mirrors, gradients, and all of these things can be layered together in a million different ways. It’s virtually an infinite amount of options, each of which can be outstanding for some applications yet completely counterproductive for others. That’s what we’re here to figure out: what makes sense for paintball, and what makes sense for me?
#1: Brightness (aka “VLT”)
The most important thing in a lens is making sure it gives you all the light your eyes need. Light = information, and you want to make sure your eyes have all the information required to make the smartest decisions on the paintball field. Optimal brightness is achieved when all essential light is transmitted and all excessive light is blocked.
VLT stands for “visible light transmission” and represents the percentage of light that a lens (or any transparent barrier) allows to pass through. The higher the VLT%, the more transparent that lens is and the more light it allows through. Naturally, the lower the VLT%, the more light is blocked, making the lens (and received image) darker.
There doesn’t seem to be a universally accepted scale to help categorize VLT values into functional categories, but in general it seems that the following VLT ranges qualify as generally accepted ranges:
|Dark as shit
It’s really hard to give you an idea of what a single VLT value means compared to another because the environmental conditions make a big difference, but to help you visualize just how different these ranges can be in different settings here are a few examples I found online of how the VLT spectrum can influence the appearance of a landscape.
Example 1/3 of VLT (photo credit)
Example 2/3 of VLT (photo credit)
Example 3/3 of VLT (photo credit)
Knowing where you plan to use your lens should give you the starting point for what VLT value is best for you. If you play in shady areas or cloudy climates, you’re most likely going to want a VLT of ~50% or higher. Those in really bright environments will probably want a VLT between 20%-40%. Better to have more than enough light than not enough at all, so always err on the side of brighter rather than darker.
#2: Contrast (Color/Tint)
After you figure out the right amount of light you need (VLT value), it’s time to figure out which colors you want to see, and which (if any) you want to filter out. This is what creates “contrast”, and it is primarily determined by your lens’ base color (aka “tint”). This is different than the color of any mirror finish your lens might have on it, although the mirrors do influence contrast and we will talk about that later.
You probably remember learning that the reason we see color at all is because the object we’re looking at is reflecting a specific wavelength of light back at our eyes while absorbing all other wavelengths. If something looks red for example, it’s because we are seeing the ‘red’ wavelength of the visible light spectrum bounce off the object while the other wavelengths are being absorbed.
Lenses work the same way but because they are transluscent, the color of the lens is actually telling us what wavelengths of light are being allowed through more so than what wavelengths are being reflected away.
It’s important to know that all lenses filter some light (yes even Clear), so every lens color can be said to ‘reduce glare’, ‘increase contrast’, and ‘block UV rays’. Keep that in mind when reading the marketing promises of different eyewear. I’m here to help you understand the physics behind the performance claims so that you know what kind of contrast you’re looking for, and what tint options make that possible.
Here are the most common color options and how they influence contrast: