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268 Chapter 18: Effects and Environments
Exposure Controls
One of the limitations of rendering perceptually
accurate images is the limited dynamic range
of computer monitors. Dynamic range is the
ratio of the highest to lowest intensity a monitor
can produce. In a dark room this ratio is
approximately 100 to 1. In a bright room, this
drops to approximately 30 to 1. Real environments
can have dynamic r anges of 10,000 to 1, or larger.
Exposure Cont rols (page 3–289) map light energ y
values to colors. T hey affect the brightness and
contrast of both rendered images and view port
displays. They don’t affect the actual lighting levels
in the scene, but only how those levels are mapped
to a valid display range.
•
Automatic Exposure Control (page 3–291)
• Logarithmic Exposure Control (page 3–293)
• Linear Exposure Control (page 3–292)
• Pseudo Color Exposure Control (page 3–296)
Env ironment Pa nel
Rendering menu > Environment > Environment and
Effects d ialog > Environment panel
Use the Environment panel to:
• Setandanimatethebackgroundcolor.
• Use an image in the background of the viewport
and rendered scene (screen environment) or
use texture maps as spherical, cylindrical, or
shrink-wrap environments.
• Set and animate the tint and
ambient light
(page 3–1002)
globally.
• Use atmospheric plug-ins, such as volumetric
light, in the scene.
A tmospheres are
plug-in components (page
3–1089)
that create light e ffects such as fire
(page 3–272)
, fog (page 3–278) , volume fog
(page 3–280)
,and volume light (page 3–284) .
•Apply
exposure controls (page 3–289) to
renderings.
See also
Exposure Controls (page 3–289)
Procedures
To access environment functions, do one of the
following:
•ChooseRendering>Environment.
• On the Environment a nd Effects dialog, click
the Environment tab.
To set the ba ckgr ound color:
1.
Choose Render ing > Environment.
The Environment panel appears.
2. In the Background group, click the color
swatch.
A
Color Selector (page 1–157) appears.
3. Use the Color Selector to change the
background color.
TheRenderernowusesthiscolorasa
background.
To choose an envi ronment ma p:
1.
Display the Material Editor.
You adjust the map’s p ar ameters w ith the
Material Editor.
2. Choose Rendering > Environment.
3. Under Background on the Environment panel,
do one of the f ollowing:
•ClicktheEnvironmentMapbutton.The
Material/Map Browser appears. Choose a
map type from the list.
•DragamaptotheEnvironmentMapbutton.
Youcandothisfromamapdisplayedinone
oftheMaterialEditor’ssampleslots,orfrom
any m ap button that has been assigned,