What is color temperature?
Color temperature is a way to describe the light appearance provided by a light source. It is measured in degrees of Kelvin (K) on a scale from 1,000 to 10,000. Typically, commercial and residential lighting application Kelvin temperatures fall somewhere on a scale from 2000K to 6500K. A light source’s (lamp’s) color temperature lets us know what the look and feel of the light produced will be.
The color temperature of a light source is assigned using the basis of correlated color temperature (CCT).
For example, if you heat up a metal object, the object appears to glow. Depending on the Kelvin temperature that the metal object is being heated at, the glow will be various colors, such as orange, yellow or blue. The color temperature of light source is meant to replicate the Kelvin temperature of the metal object.
Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, manufacturing, astrophysics, horticulture, and other fields
Color temperature is conventionally expressed in kelvins, using the symbol K, a unit of measure for absolute temperature.
Color temperatures over 5000 K are called “cool colors” (bluish white), while lower color temperatures (2700–3000 K) are called “warm colors” (yellowish white through red)
|1700 K||Match flame, low pressure sodium lamps (LPS/SOX)|
|1850 K||Candle flame, sunset/sunrise|
|2400 K||Standard incandescent lamps|
|2550 K||Soft white incandescent lamps|
|2700 K||“Soft white” compact fluorescent and LED lamps|
|3000 K||Warm white compact fluorescent and LED lamps|
|3200 K||Studio lamps, photofloods, etc.|
|3350 K||Studio “CP” light|
|4100 – 4150 K||Moonlight|
|5000 K||Horizon daylight|
|5000 K||Tubular fluorescent lamps or cool white / daylightcompact fluorescent lamps (CFL)|
|5500 – 6000 K||Vertical daylight, electronic flash|
|6200 K||Xenon short-arc lamp|
|6500 K||Daylight, overcast|
|6500 – 9500 K||LCD or CRT screen|
|15,000 – 27,000 K||Clear blue poleward sky|
At the lower end of the scale, from 2000K to 3000K, the light produced is called “warm white” and ranges from orange to yellow-white in appearance.
Color temperatures between 3100K and 4500K are referred to as “cool white” or “bright white.”
Above 4500K brings us into the “daylight” color temperature of light. Light bulbs (lamps) with color temperatures of 4500K and above will give off a blue-white light that mimics daylight.