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1296 Chapter 15: Lights and Cameras
Sk ylight
Create panel > Lights > Sta ndard > Skylight button
Create menu > Lights > Sk ylight
The Skylight lig ht models daylight. It is meant for
use with t he Light Tracer (page 3–44).Youcanset
the color of the sky or assign it a map. The sky is
modeled as a dome above the scene.
Model rendered with a single skylight, and light tracing
When you render with the default scanline renderer
(page 3–38), Skylight works best with advanced
lighting: either the Light Tracer, or radiosity (page
3–51).
Wa rning: When you render with the mental ray renderer
(page 3–78), objects illuminated by a Skylight app e ar
dark unless you turn on Final Gathering (page 3–940).
ThetoggleforFinalGatheringisontheFinal Gather
rollout (page 3–111) of the Render Scene dialog.
A sk ylight is modeled as a dome above the scene.
Tip: There are several ways to model daylight in
3dsMax,butifyouusetheLightTracer,aSkylight
often g ives the best results.
Tip: If you encounter visual anomalies w hen
rendering a bump-mapped material with a
Skylight, convert the material to an Advanced
Lighting Override material (page 2–1601) and then
reduce the Indirect Light Bump Scale value.
Using a Map with the Sk ylight
If you use a m ap with a Skylig ht, the following
guidelines can improve its effect:
• Makesurethatthemappingcoordinatesare
spherical or cylindrical.
• Forlighttracing,makesureyouusesufficient
samples. A go o d rule of thumb is to use at least
1,000 samples: set Initial Sample Spacing to 8x8
or4x4,andincreasethevalueofFilterSizeto
2.0.
• Use an image-processing application to blur the
map before you use it. With a blurred map, you
can use fewer samples to obtain good results.
When used with Skylight, a blurred m ap will
still render well.
Beawarethatusingsufficientsampleswitha
mapped Skylight will take longer to render than if
the light were not mapped.