A Brief Introduction
We are starting to
embrace the importance of good lighting.
Eighty percent of our decisions are based on what we see. Seeing is the
interaction between the eye, the object viewed and light. Light, determines how
we perceive the object in view. So
SEEING REALLY IS BELIEVING!!!
Lighting controls visual
impression. In order to achieve a desired environment, knowing how to use light
and lighting is essential. Even with smaller budgets, the impact can be significant
– remember, in the dark, it only takes a flashlight to create a visible monster.
Know your lights
Since we can acknowledge
the importance of how light cascades on an exposed object, we need to educate
ourselves on how our choice of lighting interacts with the object when it comes
to color representation.
It is important that a lighting
environment enhances the objects being illuminated to make them most
appealing. The red color of the tomato,
for example, must be vibrant to appeal to the customer in the grocery store.
Quality, not quantity of
light
Elements like color of
light, degree or beam spread and brightness are also important factors to the environment
and the object being illuminated. A
display may be made dull by a poor choice of lighting. The quantity of light
does not create good lighting. For
example, a large floodlight provides the quantity of light needed for a night
time outdoor ball game, but would simply be the wrong choice for most exhibit
or retail displays. Instead, to catch our attention, narrow beam spotlights should
be used to make products or areas “pop” or stand out while playing down the surroundings. This type of lighting creates contrast
through interaction between darker and well illuminated sections.
Energy efficiency
Energy efficiency is
increasingly important in all lighting decisions, both for economic reasons and
for sustainability reasons. With the
development of emerging technology, it is possible to make good lighting
choices for a project for illumination purposes, as well as for the well-being
of our planet. Ordinary light bulbs
produce 95 % heat and only 5 % light and often require additional cooling
units, which make them quite inefficient when it comes to energy consumption.
There are many options today that allow for a more energy efficient lighting
solutions. More information on this
subject can be found in the Tools and
Products section of this report.
Light – not only for
exposure
Light can make a display
or retail environment more competitive and attractive, but it is also a
workplace where staff and visitors should feel at home. Research shows that our
sight grows weaker as our age advances. A 60-year-old requires a lot more light
than a 20-year-old in order to experience the same brightness. At the same time, the 60 year olds eyes are more
sensitive to sharp light, which is why properly placed sources of light are of the
upmost importance.
Light and Vision
What is Light?
Describing and understanding
light requires that we understand a few key terms. Below are short descriptions
of five commonly used terms and a short introduction to them.
Color temperature K =
Kelvin
Color temperature describes how light
appears when the human eye looks directly at the illuminated source. Color
temperature is measured by a unit called the kelvin (K), a scale that starts at
absolute zero (-1273 degrees C). Imagine heating a bar of steel and observing
the color of the bar at increasing temperatures. At some point the bar will
appear to glow a dull red. As heat is added, the dull red turns to yellow, then
to white, then to bluish white and finally to blue.
A light bulb that produces light
perceived as a yellowish white color output will have a color temperature of
around 2700K. As the color temperature increases to 3000K - 3500K, the color of
the light appears less yellow and more white. When the color temperature is
5000K or higher the light produced appears bluish white. The color temperature
of daylight varies, but is often in the 5000K to 7000K range.
It is important to note that color
temperature is not the same as color rendering. The color temperature of a
light source does not describe or predict the ability of that light source to
render color accurately.
Lux = Luminous intensity
Lux is the measure of illumination on a surface at a particular distance
from the source of the light. It answers
the question – how well is this object illuminated at a particular distance
from the light source? For indoor work,
a luminous intensity of 500 up to a 1000 lux is common. In our homes, the
intensity is often around 200 lux. These numbers pale in comparison to the
luminous intensity on a sunny day, which can exceed 100,000 lux!
Candela (cd)
Candela is the
measurement of light brightness in a certain direction. Knowledge of the
Candela of a light source allows us to calculate how much light will reach a
specific surface. Candela answers the question – How well is an object
illuminated at a particular distance from a light source?
Lumens are a property of light that more and more people are
aware of when choosing which type of light source to use. It measures how
effectively a lamp uses the supplied energy (watt). An effective light source
will turn the supplied energy to light, while a more ineffective one will turn
it into heat.
Color rendering (Ra)
Color rendering describes how a light source makes the color of an
object appear to human eyes and how well subtle variations in color shades are
revealed. The Color Rendering Index (CRI) is a scale from 0 to 100 percent
indicating how accurate a "given" light source is at rendering color
when compared to a "reference" light source.
The higher the CRI, the better the color rendering ability. Light
sources with a CRI of 85 to 90 are considered good at color rendering. Light
sources with a CRI of 90 or higher are excellent at color rendering and should
be used for tasks requiring the most accurate color discrimination.
It is important to note that CRI is independent of color
temperature (see discussion of color temperature). Examples: A 2700K
("warm") color temperature incandescent light source has a CRI of
100. One 5000K ("daylight") color temperature fluorescent light
source has a CRI of 75 and another with the same color temperature has a CRI of
90.
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Tools and Products
The Tools
Good lighting application
engineers and good tools can create wonderful illumination results, even with
small budgets. Product development in the light area may be greater than even
before. The choices that can be
presented for consideration offer many different qualities, types and price
points of lights today.
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Incandescent light bulbs
Incandescent light bulbs,
or lamps, have always had a good rating on color rendering index (RA), but are
now making way for a new generation of energy-efficient light sources. Why?
Because only 3% of the energy they consume becomes light – the rest becomes
heat radiation.
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Line voltage halogen
Used mainly in home
lighting and more common in Europe than the U.S. Only 6-7% of energy consumed
becomes light. Approx. 10% less system efficiency than low voltage halogen
bulbs, mainly due to a larger burner arrangement inside of the lamp. No transformer
is required.
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Low voltage halogen lamps
Widely used in exhibition
and retail lighting during the 1990s. Good color rendering, but consumes too
much energy to be suitable for the modern retail lighting of today. Lamp
lifespan is also too short. Requires a transformer to operate. Only 6-7% of
energy consumed becomes light.
Compact fluorescent
lamps, CFL
Fluorescent lamps are
good for ambient (general) lighting but are not the ideal choice for showcases.
There are optical difficulties in controlling light flow from the lamps as
there are no reflectors or optics integrated into the lamps. Requires a ballast
to operate, which is usually built into the lamp. Approx. 20% of energy
consumed becomes light.
Linear fluorescent lamps
Many types. Nowadays, T5 and T4 are most common. Linear
fluorescent lamps are good for ambient (general) lighting but are not the ideal
choice for showcases. There are optical difficulties in controlling light flow
from the lamps as there are no reflectors or optics. Requires a ballast to operate which is
usually built into the light fixture. Approx. 25% of energy consumed becomes
light.
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Discharge lamps (HID)
Single-ended,
double-ended or also available as PAR lamps. Currently the most widely used
light sources in European exhibition and retail lighting. Double-ended types
usually have a longer lifespan, but difficult to design narrow beam spread
reflectors. Approx. 25% of energy consumed becomes light. Requires electronic ballast
to operate which is usually built into the light fixture.
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”PAR” HID-lamps
Widely used in North
America, but have a limited lifespan due to their design. Difficult to use for
accent lighting applications because of inherent optical limitations in
controlling light flow. Approx. 15-20% of energy consumed becomes light due to
the optical design of the reflector. Pros
& cons: can be used in less expensive light fixture, but more expensive
lamps.
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Products
Here
you can find out more about which products lighting
professionals use in trade shows, stores and other locations.
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Arm lights for
exhibitions and display systems
Arm lights are suitable
for use in temporary installations or when ceiling height does not allow for
other types of lighting to be installed. Can be mounted on a permanent wall
section or on portable display systems.
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Track Lighting Systems
Tracks allow the user to
connect several lights to a track with the flexibility of moving the light
along the track where needed. Great flexibility in the event that displays are
reconfigured over time. Tracks can be
used wherever needed for accent and ambient lighting. Surface mounted, recessed or suspended installations
are possible.
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LED
LED (Light Emitting
Diodes) can also used, but remember – cooling is of the utmost importance to
ensure the longevity of the LED. High
quality fixture have custom heat sinks incorporated into the fixture to achieve
the necessary cooling. Available in
various color temperatures of white as well as color changing versions.
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Spotlights
Spotlights are a flexible
and efficient way of focusing light where you need it most. Spotlights draw
attention to your message and highlight your products.
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Down Lights
Down lights create
ambient (general) lighting. Pull-out and rotational down lights can also be
used as spotlights. Light levels should not differ by more than ~30% at any
point across the floor.
