Quickly, before I recommend a specific color temperature for outdoor security lights or motion lights, let me briefly explain a few things:
What is light?
Well, light is a electromagnetic wave or a mixture of various wavelengths that our eyes can ‘see’. Actually it’s the rods and cones in our eyes that get the job done – more on that in a minute.
Is light colored?
Light itself is not colored. Light is simply electromagnetic waves of various wavelengths within the visible spectrum. The color is our brain’s translation/interpretation of those wavelengths.
What is color temperature?
It is a technical representation of the perceived color of light. The visible spectrum ranges from deep red (long wavelengths) through yellow, green, blue, all the way to deep violet (short wavelengths). Color temperature is measured in degrees Kelvin (K).
The Color Temperature Of Light Bulbs
When you look at a package of LED light bulbs, there will be a color temperature rating.
The color or hue will range from a very soft yellow-red on up to a white, even bluish.
Many manufacturers list the equivalent color temperature in Kelvin (K). That said, they market words like “soft”, “warm”, “cool”, etc.. which is arbitrary. It is the color in degrees Kelvin which is the important factor.
A 2700K light bulb gives off a very soft yellow hue, similar to the standard incandescent bulb. These are popular in homes.
3000K bulbs are still warm but with a bit more ‘white’ in them. I like these in homes too.
A 5000K bulb is considered to be “horizon daylight” (Wikipedia’s term) and is pretty much ‘white’.
6000K is the color temperature of “vertical daylight” (the sunlight above the atmosphere), similar to a professional camera’s electronic flash.
Bulbs are available in a variety of color temperatures. I find that once you get up to 4000K, the bulb hue appears to be pretty close to white.
Best Color Temperature For Security Lights
Okay so let me answer this…
5000K – 6000K light produces higher contrast as seen by our eyes.
For the sake of security lighting and outdoor motion flood lights purposed for security, I would go with at least 5000K color temperature bulbs or floods.
These are the specific LED security bulbs (floods) that I use:
Important For Security Lighting
1. Sufficient lumens (brightness) to illuminate the area.
2. Enough light to quickly identify objects, people, movement.
3. Good color discernment.
While a ‘warmer’ color temperature might look better for specific landscaping appeal, when it comes to home security you will want to bathe the area in bright ‘white’ 5000K natural or even ‘cool’ 6000K (a hint of blue) light.
How Do Our Eyes See Color?
Light waves enter the eye as they travel through the pupil and hits the retina.
The retina has cells that sense the light (rods and cones).
Rods sense the intensity of the light.
Cones sense the wavelength (translated to color).
There are 3 types of cones and they’re especially sensitive to red, green, and blue – but also wavelengths in-between to a lesser extent.
When light waves activate the various cone groups, a chemical reaction sends messages to the brain which interprets what color (wavelength) the light is.
data sources include Wikipedia