Color temperature and color rendition are among the important
factors that affect the appearance of a lighted area and the things within it.
These factors can help to evaluate the type of lighting needed for particular
These terms describe two different characteristics of lamps.
Simply put, color temperature refers to the color of the light source itself,
while color rendition refers to the relative appearance of colors of objects under
a light source.
Correlated Color Temperature (CCT) at its most basic level
is usually described as “warm” (yellowish) or “cool” (bluish). It is conveyed
as degrees Kelvin (K). Warm light has a lower CCT than cool light. A warm light that has a typical yellowish glow
has a color temperature of around 2700K. A cool light that has a typical
blueish glow has a color temperature of around 4100K.
Color temperature affects the appearance and feel of a
lighted space. Higher (or cooler) color temperatures are brighter, closer in
appearance to mid-day sunlight. Lamps at these levels are best used for reading
or other tasks. Lower (or warmer) color
temperatures are softer and are better used for mood or area lighting.
Color rendition refers to how accurately colors appear under
a light source. Color rendition is measured by the Color Rendering Index (CRI)
which is a range from 0 to 100 with 100 representing the most accurate (or
natural) color characteristics. Lamps with lower CRI values can indicate that
some colors may appear unnatural when illuminated by the lamp. A good rule of
thumb is to use lamps with a CRI of 80 or for accurate color rendering. A CRI
of 90 or higher is considered excellent.
Tasks that would require a high CRI lamp would be anything
that requires close inspection, such as examining paint color charts. Another
would be for illuminating television or movie sets.
CLICK HERE TEST
- For the most accurate comparison purposes the
CRI should be used to compare lamps with the same CCT.
- Unlike in the past, fluorescent lamps can now be
considered part of you decision now they are available with CRIs over 90.
- Use lamps with the same CRI and CCT ratings to give
your lighting a more uniform appearance.