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Advanced Lighting Override Material 1411
Impor tant: The
mental ray renderer (page 3–77) does
not support the Advanced Li ghting Override material.
Obtaining a Better Image
Materialsthatusedefaultsettingscanbehighly
reflective. This ca n lead to overexposed or
washed-out radiosity solutions. In general, the
bestwaytoadjustthisistoreducetheHSV
Value (V) of a material color; or, for a bitmapped
material, reduce the RG B Level. In some situations,
Radiosity Override ca n improve the appearance
of the radiosity solution. Examples of situations
where Radiosity Override can help include color
bleeding and large dark areas:
• YoumightwanttoreduceReflectanceScale
or Color Bleed when a large area of color (for
example, a red carpet in a room with white
walls) creates excessive color bleeding. This
mightbephysicallyaccurate,buttheeyeadjusts
for such effects, and the radiosit y result might
look better with less reflectance or less color
bleeding.
Left: E xcessive bleeding of the floor color onto the walls
and ceiling.
Right: R adiosity Override material reduces the floor’s
reflectance, causing less bleeding.
• You might want to increase Reflectance Scale
when the scene includes a large dark area (for
example, a black floor). This can lead to a very
dark radiosity result. You can maintain the
floor’s color but increase reflectance, giving the
solution the colors you want while increasing
its brig htness.
The room is lit only by spotlights pointed at the floor.
Increasing reflectance of the floo r brightens the entire
room.
Tip: Check t he reflectance and transmittance
display (page 2–1274)
to get an idea of how
the current material will affect the radiosity
solution or light-traced rendering.
Creat ing Special E f fects
Self-illumination (page 2–1328) makes an object
appear to glow in ordinary renderings, but does
not contribute energy to the radiosity solution. To
have radiosity processing take a self-il luminating
material into account, make this material the base
material of Advanced Lighting Override, then
increasethevalueofLuminanceScale.
Upper left: By default, self -illu minated neon lights do not
influence the scene light.
Right: Advanced Lighting Override material scales the neon
lights’ Luminance so t he radiosity solution can tak e it into
account.