Theatre Design & Technology - Summer 1982 - 20

The Control of Electrical Light Sources *
by Karl Heinz Bodenhausen

The control of the output of light sources is as old as lighting technology itself. Even before the use of electric light
sources petroleum lamps were "controlled" in stage lighting
in order to achieve particular moods. Petroleum lamps were
later replaced by incandescent lamps. The technology of incandescent lamp control is generally known. The conditions
prevailing during the control of standard incandescent lamps
is easily understood. Complications seldom occur.
Recent developments have provided us in recent years with
a wide variety of new lamps, including halogen incandescent
lamps, metal-vapor lamps, short-arcing lamps, fluorescent
lamps, and trispectral lamps. The characteristic behavior of
these new lamps during output control is complicated and
highly complex. Some of the questions which still remain unanswered include: When does the halogen cyclic process
cease during output control? What fluorescent lamps are suitable and unsuitable for output control? What prerequisites are
necessary for output control? How does the color location of
lamps with numerous fill substances change? What effect
does output control have upon lamp service life and light
yield?
Even experts in the lighting industry give incorrect answers
to such questions, often, in part, due to ignorance, as a recent
example shows: A noted German theatre built an adjustable
horizontal lighting system for a new production. A day before
the premiere of the production it was found that the incandescent lamps used were unsuitable despite the recommendation of the salesman that the system was suitable for
output control.
Admittedly, we manufacturers of lamps today still are not
completely familiar with all of the characteristics of our products. Furthermore, lamp manufacturers are not eager to address the field of output control. We lamp manufacturers attempt to optimally design lamps for their designed output. Any
attempt at output control, however, ignores such predetermined designed output! Today when lamp manufacturers
Figure 1: Lamp Voltage and Lamp Current

&

c

*





Table of Contents for the Digital Edition of Theatre Design & Technology - Summer 1982

Contents
Theatre Design & Technology - Summer 1982 - 1
Theatre Design & Technology - Summer 1982 - 2
Theatre Design & Technology - Summer 1982 - 3
Theatre Design & Technology - Summer 1982 - Contents
Theatre Design & Technology - Summer 1982 - 5
Theatre Design & Technology - Summer 1982 - 6
Theatre Design & Technology - Summer 1982 - 7
Theatre Design & Technology - Summer 1982 - 8
Theatre Design & Technology - Summer 1982 - 9
Theatre Design & Technology - Summer 1982 - 10
Theatre Design & Technology - Summer 1982 - 11
Theatre Design & Technology - Summer 1982 - 12
Theatre Design & Technology - Summer 1982 - 13
Theatre Design & Technology - Summer 1982 - 14
Theatre Design & Technology - Summer 1982 - 15
Theatre Design & Technology - Summer 1982 - 16
Theatre Design & Technology - Summer 1982 - 17
Theatre Design & Technology - Summer 1982 - 18
Theatre Design & Technology - Summer 1982 - 19
Theatre Design & Technology - Summer 1982 - 20
Theatre Design & Technology - Summer 1982 - 21
Theatre Design & Technology - Summer 1982 - 22
Theatre Design & Technology - Summer 1982 - 23
Theatre Design & Technology - Summer 1982 - 24
Theatre Design & Technology - Summer 1982 - 25
Theatre Design & Technology - Summer 1982 - 26
Theatre Design & Technology - Summer 1982 - 27
Theatre Design & Technology - Summer 1982 - 28
Theatre Design & Technology - Summer 1982 - 29
Theatre Design & Technology - Summer 1982 - 30
Theatre Design & Technology - Summer 1982 - 31
Theatre Design & Technology - Summer 1982 - 32
Theatre Design & Technology - Summer 1982 - 33
Theatre Design & Technology - Summer 1982 - 34
Theatre Design & Technology - Summer 1982 - 35
Theatre Design & Technology - Summer 1982 - 36
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