When shopping for auxiliary lights for your vehicle, perhaps you’ve wondered: do I go with yellow lenses or clear lenses? Then maybe you thought, why would I even consider yellow lenses? Yellow lenses excel in dust and snow. But have you ever wondered why do yellow fog lenses work for dust and snow? Let’s first talk about color temperature with regards to lighting.
Color Temperature
Color temperature measures one characteristic of visible light and is rated against a Kelvin scale (K). Generally, the human eye functions more effectively when objects are illuminated by a light source that is closest to the mid-day sun, which is around 5,400K. Ken Turzinski, President of TYRI Lights, says a candle is about 2,000K, whereas a clear sky can be as much as 6,500K.
Ken points out that a higher white light has a lot of “blue” light in it, which is the reason the sky is blue. This has a shorter wavelength and therefore refracts more or scatters when it passes through vapor in the atmosphere.
“At sunrise and sunset, the light from the sun has to travel a much greater distance through the atmosphere,” Ken says, “Red, Orange, and yellow have the longest wavelengths so they can penetrate the atmosphere hence colorful sunsets.”
Then Why Not Red Fog Lights?
Knowing this, why don’t we use red fog lights?
“This comes back to how our eyes see,” says Ken. “At night our eyes rely more on the rods [versus cones] to see. Yellow is a more visible color and gives better depth perception.”
While red and orange light is easier on the eyes and causes less fatigue in the dark, depth perception suffers. Red and orange, however, are good colors for taillights and turn signals but not so good when you’re trying to avoid an obstacle.
So Why Not Just Lots of White Light?
There is a temptation to have a bright light to match that of the midday sun. However, this can be a bit too much in many circumstances. Increasing the Kelvin temperature also increases the blue hue of an LED, which can potentially cause glare and irritation to the eye and lead to fatigue over long periods of time.
In some applications where other conditions such as dust or snow affect vision, a lower temperature light may be more suitable as it delivers less glare. This is the case with a yellow or amber lens.
Why Yellow Fog Lenses Work for Dust and Snow
Yellow lenses on lights serve specific purposes and can have advantages in certain situations. Yellow lenses are beneficial in low visibility situations, such as dust and snow or even fog. But why do yellow fog lenses work for dust and snow?
“It’s all physics,” says Ken. “The reason the yellow light color works so well in dust and fog is because of the combination of the wavelength of the yellow color along with the refractive index of the material that’s in the air.”
Ken goes on to say that yellow is the best color to penetrate dust and fog. White Light, on the other hand, is comprised of the full spectrum of colors and therefore isn’t measured in wavelength but rather color temperature.
Yellow lenses also tend to penetrate fog and haze better, making it easier to see in these conditions.
The reduced glare can also mean less eyestrain. Yellow light is generally less harsh on your eyes vs. white light. This is especially true during nighttime driving. Yellow light also provides enhanced contrast and depth perception making it easier to see objects in the road, especially in low-light situations.
Yellow Lenses Do Have Downsides...
One negative aspect for yellow lenses is a reduction in effective lumens, or the measure of actual light being emitted. Since something must be done to change the light’s color temperature to achieve the yellow or amber hue (such as a filter) some of that lumen output is going to be reduced. So while they can perform better in low-visibility situations, they aren’t going to be quite as bright.
TYRI Lights With Available Yellow Lenses
If you’re looking for lights with yellow lenses, TRYI has choices. Our TYRI 1010, 1313, D18, and V12 light bar models all have available yellow covers to make them perform great in dust and fog.
Additionally, there’s the TYRI INTELLilight. INTELLilight is our new, patented and revolutionary lighting system. It allows you to change the color temperature and intensity as well as the ability to group and regroup lights using either a remote or app. This lets you have the ability to have warmer yellow light or a cooler white light all in one lamp.