A Review
the chemical containing the hue is molecularly linked
with the clear base. This means that the clear base
is heated to open molecular pores in its surface, and
then the dye is applied, so that the hue is “stained”
into the clear base. Although many different mate-
rials are used for the base in colored filters, they’re
still often generically referred to as gel.” When color
media is inserted in front of an instrument’s lens, it is
often kept rigid by being packaged in a gel frame.
Because all wavelengths of the visual spectrum
stopped by color filters transform into heat, a more
saturated color filter will absorb a greater amount of
heat. Under intense heat, dyes “move away” from the
hot center, resulting in a faded gel. Since the saturated
color will get hotter faster, the hue of the color will
comparably fade more rapidly than a less saturated
filter. Saturated greens and blues absorb the most
infrared energy, so they’re the colors most susceptible
to lose their hue due to heat. Technological improve-
ments in lamp design have increased the intensity and
temperature output of instruments. This has resulted
in numerous tactics being adopted to reduce the
amount of heat absorbed by the color media in an
effort to retain the hue.
One tactic begins with color selection. Some color
manufacturers suggest choosing filters that transmit
high amounts of light in the 700- nanometer wave-
length range. The nanometer range is shown in the
spectral energy distribution curves included in most
color swatchbooks. Other color manufacturers
suggest reducing the intensity of the hot spot in light
beams by altering the relationship between the lamp
and reflector of ellipsoidals, also known as aligning
the instruments to a “flat field.”
All color manufacturers recommend increasing
the distance between the lens and the filter, or pro-
viding airflow between the two. Practical “distance”
workarounds include taping the color onto the front
of a tophat or barndoor, or adding a color extender
between the two. Another tactic commonly employed
involves adding a second piece of media between
the lens and color media commonly known as “heat
shield,” which is constructed of Teflon™. Some man-
ufacturers claim that “heat shield” has a higher melt-
ing temperature, so it absorbs much of the convected
heat. Others contend that there’s no significant drop
in beam temperature on the color media when the
material is added. If “heat shield” is added between
lens and color media, air space between it and the gel
must be maintained. Otherwise the two pieces become
heat-welded together and the color is lost. Regardless
of that debate, all agree that the most effective heat
shield is a special dichroic glass filter. Dichroic glass
products actually reflect infrared and ultraviolet
energy away from the color filter, and protects the
color filter from convected heat. Since this form of
heat shield is very expensive, however, a combination
of the other suggestions is often employed to reduce
the loss of hue in the color filter instead.
One difficulty often encountered with many ellip-
soidals is achieving a barrel focus that produces an
equally soft edge on both the shuttered and unshut-
tered portions of the light beam. Although the barrel
focus can be adjusted to many different positions, in
many cases a soft edge on one side of the beam will
result in a sharp edge on the opposite side. Many dif-
ferent diffusion materials known as “frosts” can be
inserted in the color frame holder, which alters all
edges of the beam to equal softness.
Technology and innovation are so swift in this
facet of the industry that keeping track of the changes
and improvements is a challenge. Although swatch
books give some indication of the wide range of tasks
that media can perform, experimentation by the light-
ing designer in the light lab or the lighting rental shop
is the true test to determine accurate application and
This concludes a rudimentary review of vari-
ous physical and conceptual elements that form a
basic framework of practical knowledge required
for a lighting design to begin to take place. The next
step is to examine the artistic and technical hierar-
chy that exists in a typical North American theatrical
The role of the lighting designer exists within an orga-
nization of other personnel, and the designer must
understand his or her role within this group. Every
production has a staff that executes specific tasks.
Although the titles may change or the responsibilities
may shift from one show to another, the tasks must
still be accomplished.
The Management and Creative Staff
In professional for-profit productions, the manage-
ment staff starts with a producer, who oversees the
entire production, and initially recruits investors to
provide the money to support the show. Everyone
answers to the producer. The general manager over-
sees the collection, budgeting, and distribution of
those monies. A company manager is typically the
general manager’s on-site representative in the the-
atre, overseeing many on-site expenditures, box office
income, and addresses offstage needs for the perform-
ers or production staff. These responsibilities may be
delegated to other members of the management staff.

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