WHO IS THIS KELVIN GUY?
For a real-world example, think of an
incandescent filament. As the filament gets
hotter, it first begins to glow red then orange,
yellow, and so on. These color changes are
measured as heat values in kelvin, but
correlate to color spectrum changes, too. By
applying the Kelvin scale to these specific
hues or color ranges, it’s possible to select
light values favorable for specific phases of
plant photobiology. Kelvin can also be used
to identify full-spectrum lights that most
closely approximate sunlight.
Is Blue Cool or Hot?
Let’s look at this concept a little more closely.
Light sources can be somewhat classified
based on their kelvin values using a scale
from 1,000-8,000 K. Here are some general
examples to give you an idea of how the
scale relates to different types of light:
• Candlelight: 1,800-1,930 K
• Sunlight at Sunrise or Sunset: 2,000-3,000 K
• High Pressure Sodium (HPS): 2,200 K
• Incandescent: 2,700-3,000 K
• Compact Fluorescent (CFL):
2,700-6,500 K (various)
• Metal Halide (MH): 3,200-5,500K (various)
• Sunlight at Noon on a Clear Day:
5,000-5,400 K
COLOR
TEMPERATURE
& YOUR HOME
LIGHTING
“
In color psychology,
humans tend to
associate blue
hues with cooler
environments, often
defining them as
calmer, chillier shades.
However, blue has a
higher kelvin rating
and color temperature
than that of red,
orange, or yellow light.
”
If you think the value of color
temperature is limited to the
confines of your growroom,
guess again. The technology
has widespread uses, some
of which touch pretty close to
home. Color temperature is
used in photography, publishing, the film industry, and astrophysics. It is also a key component in lighting for business
and residential applications.
Take a look at your stash of
everyday lightbulbs and you’re
likely to see they include a
kelvin range. Popular ENERGY
STAR* bulbs are rated for both
energy efficiency and color
temperature. Their color temperature ratings can help you
identify and consistently purchase the light hue, or hues,
that function best for the room
or task you have in mind.
Generally, a color temperature
range of 2,000-3,000 K produces
warm, cozy yellow light great for a
bedroom, dining room, or family
room. A higher range of 3,1004,500 K produces cool white
lighting effective for a kitchen
workstation or a desk lamp.
Lighting in the white, blue range
of 4,600-6,500 K works best in
spaces where visibility is critical,
such as stairways, entryways, and
garage workspaces.
*ENERGY STAR is a joint venture
between the US Environmental
Protection agency (EPA) and the US
Department of Energy (DOE) tasked
with establishing standards for energy
efficient products. Goods that carry
the ENERGY STAR logo can be up
to 30 per cent more energy efficient
than their unrated counterparts.
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Maximum Yield USA | December 2016