2008

Interface
Brightness Adjusts the brightness of the converted colors. Range=0 to 200.
Default=50.
This parameter is animatable.
Contrast Adjusts the contrast of the converted colors. Range=0 to 100.
Default=50.
This parameter is animatable.
Exposure Value Adjusts the overall brightness of the rendering. Range=-5.0
to 5.0; Negative values make the image darker, and positive values make it
brighter. Default=0.0.
The exposure value is comparable to the exposure compensation setting in
cameras with automatic exposure. This parameter is animatable.
Physical Scale Sets a physical scale for exposure control to use with lights
that are not physically based. The result is an adjustment of the rendering
that approximates the eye's response to the scene.
Each standard light's
Multiplier on page 7859 is multiplied by the Physical Scale
value to give a light intensity value in candelas. For example, with the default
Physical Scale of 1500, a standard omni light is treated by the renderer and
radiosity as a photometric isotropic light of 1500 candelas. Physical Scale is
also factored into reflections, refractions, and self-illumination.
TIP You need to set the Physical Scale when you use ray-tracing with self
illumination. Set this value to the equivalent of the brightest light source in the
scene. This will set the appropriate conversion scale for reflections, self-illumination,
and all other non-physically based elements a material offers. In some cases, an
object might reflect or emit more light than the brightest light object in the scene;
in this case, use the object's Luminance value as the Physical Scale.
6536 | Chapter 19 Effects and Environments