Warm or Cold? Understanding Kelvin Temperature Rating

Depending on what part of the world you live in, temperature is measured in Celsius or Fahrenheit, but there is another temperature: light temperature. Light temperature is measured in a unit called ‘Kelvin’ (°K). For those in search of even great detail, in science and engineering terms, degrees Celsius and Kelvin are often referred to simultaneously… but we recommend a Google search on this one to save complicating this article any further.

What is meant by light temperature?

Light or colour temperature refers to the type of colour of light that is emitted – the higher the Kelvin output of a light, the whiter the light will appear and will sometimes even have a slight blue halo.  A light with a lower Kelvin will cast a light that is ‘warmer’ or more yellow in appearance.   

So a light with a higher rating of say 5000°K, is not necessarily more powerful than one with a rating of 3000°K – the notable different is the colour of the light they cast.

Most experts believe that the higher the Kelvin value the light is rated at the better (within reason).  Kelvin of around 5500° to 6500° closely resembles daylight, and it’s these daylight conditions that researchers say are the best for night time driving, as eye strain and fatigue is minimised.

Any higher than around 6500°K is seen as a negative, as too much of a blue colour is cast which eventually leads to darkness at the end of the visible light spectrum – exactly the opposite of what is needed in vehicle lighting!

For drivers of older vehicles whose OEM headlamp might have a lower Kelvin rating, the good news is that there are a wide variety of aftermarket Halogen and Incandescent globes on offer with higher Kelvin ratings.

Narva’s performance globe range offers 3750°K in the ‘Blue Plus 110’ and ‘Platinum Plus 130’ product line as well as 3900°K in the ‘Artic Plus 50’ globes and 4200°K in the range-topping ‘Intense Plus 30’ variants.  These are all considerable increases over standard incandescent globes which typically are rated at 2700-3300°K.

If this is not enough, driving lights such as Narva Ultima 225s offer light temperature ranging from 3940°K (Ultima Blue) to 4150°K (Ultima HID), while Narva Extremes deliver an impressive 5000°K and even more with the Ultima 215 L.E.D delivering 5700°K. The majority of our L.E.D light bar range provides temperature of around 5500°K.

Next time globes or auxiliary lighting is on the shopping list, don’t forget the Kelvin rating, your eyes will thank you.