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Lighting in 3ds Max 1133
Light s ource Color
Temperature
Hue
Sunlight at sunset or sunrise
2000 K
7
Candle flame
1750 K
5
Lighting in 3ds Max
Lightingin3dsMaxsimulatesnaturallighting.
However, st andard lights are simpler than natural
lighting. Using
photometric lights (page 2–1155)
with a radiosity solution (page 3–50) with your
lights provides a b etter model of the real world.
Intensity
The intensity of a standard light is its HSV Value.
At full value (255), the light is at its br ightest; at 0,
the light is completely dark.
Note: See Designing Materials (page 2–1239) for
more information about material color and how it
interacts with light intensity.
The intensity of a photometric light is set
by a real-world intensity value, measured
in either lumens, candelas, or lux. See
Intensity/Color/Distribution Rollout (page
2–1197)
.
Angle of Incidence
3ds Max uses a vector from the light object to t he
face, along w ith the face normal, to calculate the
angle of incidence.
A surface is fully illuminated when the angle of
incidence is 0 degrees (that is, the light source
strikes the surface perpendicularly). If the angle
of incidence increases, attenuation is in effect, or
if the light has a color, the surface intensity can be
reduced.
In other words, the position and orientation of the
light, relative to the object, are what control the
angle of incidence in a scene. The
Place Highlight
command (page 1–452)
is one way to fine-tune the
location of a light.
Attenuat ion
For standard lights, attenuation (page 3–1006)
is turned off by default. To shade or render a
scene with attenuation, you turn it on for one
or more lights. All types of standard lights
support attenuation. You can set explicitly where
attenuation begins and where it ends. This is partly
so you don’t have to worry about setting up strictly
realistic distances between lig ht objects and the
objects they il luminate. More importantly, this
featureletsyoufine-tunetheeffectofattenuation.
In outdoor scenes, attenuation can enhance
the effect of distance. (Another way to mo del
environmental effects is to use the atmospheric
settings when you render. See
Environment (page
3–267)
.) In an indoor setting, attenuation is useful
for low-intensity light sources such as candles.
Photometric lights always atten uate, using an
inverse-square falloff, as in nature. (In the case
of the IES Sun Light, its g reat intensity makes its
attenuation hardly apparent.)
R efl ected Li ght a nd Ambient Light
Rendering with the default renderer and standard
lights does not calculate the effect of lights reflected
from objects in the scene. B ecause of this, lighting
ascenewithstandardlightsoftenrequiresyouto
add more light objects than would be needed in
real life. You can, however, use
radiosity (page
3–50)
to show the results of reflected lig ht.
When you do not use a radiosity solution, you
can use the
Environment panel (page 3–268) to
adjust the color and intensit y of ambient light.
Ambient light affects contras t. The higher the
intensity of ambient light, the lower the contrast
in the scene. The color of ambient lig ht tints the
scene. Sometimes ambient light is bounced lig ht
that gets its color f rom other objects in the scene.