C haptEr 9 design Environments and systems
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to things we see. Patterns of lights or forms, for example, are filtered
and assigned meanings by observers based on their own experiences and cultural understandings. Many common optical illusions
are based on these human tendencies. We often see what we expect
to see and are conditioned to see. We are also affected by the meanings and expectations underlying what we perceive. A large blinking
red light can cause humans to respond with a sense of anxiousness.
A gray sky can engender a sense of gloom. Similarly, if we don’t see
what we expect to see, unease can develop. The light on Frankenstein’s face in old films was invariably deliberately positioned by the
director to come from a source below the face—and cast shadows
upward on the face—rather than from the more “normal” direction. The resulting feelings engendered via the unexpected direction
of the shadows formed on his face remain ingrained in the minds
of most of us who’ve seen those films.
We also know that a repetitive pattern can seem dull. But here we
note the important point that the eye will seek out and identify
any disruption of the pattern. We innately seek out unique visual
information. This is one of the fundamental driving ideas behind
many acclaimed visual works. “Visual noise,” however, can prevent
us from gaining information when it is hard to distinguish between
the visual signal and its background. A small object set against a
background pattern of bright lights may be hard to identify, in this
case because of “glare” or unwanted light within the visual field.
luminous Environments
The real world of designing luminous spatial environments ultimately demands that we have and use quantitative measures of
light intensities and many other factors in developing or selecting
light-emitting sources and important wall surfaces and deciding on
their distribution in a space. In the International System of Units,
the lumen is the basic unit of brightness measurement and in turn
defines luminous flux (the amount of energy emitted per second in
all directions). Luminous intensity refers to light intensity in a given
direction (the luminous flux that is radiated in a given direction
and within an angular unit). Luminance is the luminous intensity
emitted by a unit surface area of the light source. All these and many
other measures are commonly used by lighting designers. Normal
practice also includes use of a vast array of lighting standards that
have been developed for use as criteria for lighting levels in various
spaces (schools, offices, warehouses, corridors) and even on specific
task surfaces (such as desktops). A huge number of kinds of area,
342
to things we see. Patterns of lights or forms, for example, are filtered
and assigned meanings by observers based on their own experiences and cultural understandings. Many common optical illusions
are based on these human tendencies. We often see what we expect
to see and are conditioned to see. We are also affected by the meanings and expectations underlying what we perceive. A large blinking
red light can cause humans to respond with a sense of anxiousness.
A gray sky can engender a sense of gloom. Similarly, if we don’t see
what we expect to see, unease can develop. The light on Frankenstein’s face in old films was invariably deliberately positioned by the
director to come from a source below the face—and cast shadows
upward on the face—rather than from the more “normal” direction. The resulting feelings engendered via the unexpected direction
of the shadows formed on his face remain ingrained in the minds
of most of us who’ve seen those films.
We also know that a repetitive pattern can seem dull. But here we
note the important point that the eye will seek out and identify
any disruption of the pattern. We innately seek out unique visual
information. This is one of the fundamental driving ideas behind
many acclaimed visual works. “Visual noise,” however, can prevent
us from gaining information when it is hard to distinguish between
the visual signal and its background. A small object set against a
background pattern of bright lights may be hard to identify, in this
case because of “glare” or unwanted light within the visual field.
luminous Environments
The real world of designing luminous spatial environments ultimately demands that we have and use quantitative measures of
light intensities and many other factors in developing or selecting
light-emitting sources and important wall surfaces and deciding on
their distribution in a space. In the International System of Units,
the lumen is the basic unit of brightness measurement and in turn
defines luminous flux (the amount of energy emitted per second in
all directions). Luminous intensity refers to light intensity in a given
direction (the luminous flux that is radiated in a given direction
and within an angular unit). Luminance is the luminous intensity
emitted by a unit surface area of the light source. All these and many
other measures are commonly used by lighting designers. Normal
practice also includes use of a vast array of lighting standards that
have been developed for use as criteria for lighting levels in various
spaces (schools, offices, warehouses, corridors) and even on specific
task surfaces (such as desktops). A huge number of kinds of area,