9

1322 Chapter 15: Lights and Cameras
either case the mr Physical Sky will still b e visible
in reflections and refraction.
Toapplyamaporshadertothisparameter,click
theNonebutton.
Note: The background area in the rendered image ’s
alpha channel is always fully transparent, as is the
case in general in 3ds Max.
Inher it f rom mr Sky—Uses the equivalent settings
from the mr Sky Parameters rollout for the
remaining mr Physical Sky Parameters rollout
settings, except for Aerial Perspective. Default=on.
For further information, see Common Parameters
(page 2–1316)
Haze—The amount of particulate matter in the air.
Possible values range from 0.0 (a completely clear
day) to 15.0 (extremely overcast, or a sandstorm in
the Sahara). Default=0.0.
For details, see Haze.
Toapplyamaporshadertothisparameter,click
theNonebutton.
Horizon a nd Ground group
Hori zon Height—The vert ical position of the
horizon. Default=0.0.
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.
Toapplyamaporshadertothisparameter,click
the None button.
Tip: Some sky models neglect the influence of
bounce light from the ground, assuming only the
sky is illuminating the scene. To compare the
output of mr Sky with, for example, the IES Sky
model, one must therefore set Ground Color to
black.
After Dark group
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, stars,
high-altitude cirrus clouds that remain lit long
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.
Toapplyamaporshadertothisparameter,click
the None button.
Non-Physical Tuning group
Red/B lue Tint—Provides artistic control over the
redness of the sky lig ht. The default value of 0.0
is the physical ly correct value (calculated for a
6500K whitepoint), but can be changed with this
parameter, which ranges from -1.0 (extremely
blue) to 1.0 (extremely red).
Toapplyamaporshadertothisparameter,click
the None button.
Saturation—Provides artistic control over
saturation of the sky light. The default value of
1.0 is the physically calcula ted saturation level.
Possible values range f rom 0.0 (black and wh ite) to
2.0 (extremely high saturation).
Toapplyamaporshadertothisparameter,click
the None button.
Aerial Perspective group
Note: This parameter is for advanced users, and
functions only when you use mr Physical Sky is