You can make a photometric
light self illuminating by turning on the Light Shape Visible In
Rendering option in the
When you turn on Light
Shape Visible In Rendering, by default 3ds Max Design turns off Specular
Effects rollout. This prevents unwanted
effects if the area of the photometric light is small. Small lights
have a high luminance, and also are hard for specular rays to find:
the result can be overly bright spots in your rendering.
- If the self-illuminating photometric
light has a small area, leave Specular turned off.
- If the self-illuminating light has a
large area (for example, a skylight or a fluorescent tube), turn
Specular back on for the most realistic effect.
Photometric Lights and Self-Illuminating Materials
To make a light fixture
visible to the renderer, we recommend modeling the light fixture
with actual geometry that has a self-illuminating material applied
The square white surface
is geometry representing the light.
A photometric light
is placed at the same location.
This doesn’t pose a problem
unless you create a
solution that uses Final Gather. Final
Gather treats the self-illuminated material as an additional diffuse
light source, and the resulting rendering is too bright.
The intended effect
of the light alone.
The light plus Final
Gather creates illumination that is too bright.
If this problem arises,
do one or both of the following:
- Turn off Specular for the photometric
- Turn off Object Properties Advanced Lighting Geometric Object Radiosity
(reflective & translucent) for objects with surfaces affected
by this problem.