The CRI
rating of light sources, is an old
standard developed by the
International Commission on
Illumination (CIE). It is a
relative index which compares the
relative color reproduction ability
of one light source to another. The
maximum value of 100 is given to
tungsten light sources, therefore
all other light sources including
sunlight will have values less than
100. This was an important
reference for film
photography because tungsten
balanced film rendered
perfectly in tungsten light and
color shifted for almost all other
light sources that have lower
CRI values.
This outdated
light valuing method is mostly
irrelevant to digital photography
because all digital cameras include
compensation for color temperature
and are more accurate at 5500-6000K
than the 3200K color temperature of
tungsten light. In reality tungsten
light has an abundance of red and
infrared (heat) and is relatively
weak in the blue part of the
spectrum. In reality, light sources
that are closer to 5500K (like the
ALZO Cool Lites) will render color
better in a digital camera than
tungsten light.
Conclusion:
We include CRI ratings in our
product descriptions because many
customers requested it. In reality
we are anxiously waiting for the
CIE to develop a better index that
address the many light generation
technologies present today that are
far better than tungsten sources.
