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mr Sun 1319
For details, see Horizon Height.
Blur—The “blurriness” with which the horizon is
rendered. Default=0.1.
At 0.0 the horizon is completely sharp. Generally
only values lower than 0.5 are useful, but the full
range is up to 10.0 for a horizon that consists of
blur only, with no actual horizon at all.
Ground Color—The color of the virtual ground
plane. Note that this is a diffuse reflectance
value (t hat is, albedo). The ground appears as a
Lamber t ian reflector with this diffuse color, lit by
the sun and sky only, and does not receive any
shadows.
Tip: Some sky models neglect the influence of
bounce light from the ground, assuming only the
sky is illuminating the scene. To comp are the
output of mr Sky with, for example, the IES Sky
model, one must therefore set Ground Color to
black.
Night Color—The minimum color of the sky: The
sky will never become darker than this value. It
can be useful for adding things like moon, st ars,
high-altitudecirruscloudsthatremainlitlong
after sunset, etc. As the sun sets and the sky
darkens, the contribution from Night Color is
unaffected and remains as the base light level.
Non-Physical Tuning group
Red/B lue Tint—Provides artistic control over the
redness of the sk y light. T he default value of 0.0
isthephysicallycorrectvalue(calculatedfora
6500K whitepoint), but can be changed with t his
parameter, which ranges from -1.0 (extremely
blue) to 1.0 (extremely red).
Saturation—Provides artistic con trol over
saturation of the sk y light. The default value of
1.0 is the physically calculated satura tion level.
Possible values range from 0.0 (black and white) to
2.0 (extremely high saturation).
Aerial Perspective group
V isibility Distance—Aerial Perspective is a term
used by painters to convey how distant objects are
perceived as hazier and tinted towards the blue
end of t he spectrum. mr Sky emulates this with
the Visibilty Distance parameter. When nonzero,
it defines the “10% distance”, that is, the dist ance
at which approximately 10% of haze is visible at
a Haze level of 0.0.
mr S un
Daylight system > Modify panel > Daylight Parameters
rollout > Sunlight drop-down list > mr Sun
Create panel > Lights > Photometric > mr Sun
Create menu > Lights > Photometric Lights > mr Sun
ThemrSunlightisintendedprimarilyforuse
in the mental ray Sun & Sky combination. This
topic mainly provides information on parameters
unique to this component. A number of mr Sky
parametersarecommontoallthreeSun&Sky
comp onents. For some of those par ameters, this
topic provides a brief explanation plus a link to the
main topic with additional details.
See also
mental ray Sun & Sky (page 2–1313)
mr Sky (page 2–1318)
mr Physical Sky (page 2–1321)