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Cameras 1365
Sample Range—
The sample range (page 3–1004)
determines how much area within the shadow is
averaged. T his affects how soft the edge of the
shadow is. Range=0.01 to 50.0.
Increasing the Sample Range blends the shadow edges and
creates a smooth effect, hiding the granularity of the map.
Absolute Map B ias—When on, the bias for t he
shadow map is not normalized, but is instead
basedonafixedscaleexpressedin3dsMaxunits.
This value does not change during an animation.
You must choose the value, based on t he size of
the scene extents.
Whenoff,thebiasiscomputedrelativetotherest
of the scene, and then norm alized to 1.0. This
prov ides a common starting bias value in scenes of
any siz e. If the scene extents change, this internal
normalization can vary from f r ame to frame.
Default=off.
Tip: Leaving Absolute Map Bias off gives good
results in most situations, because the bias is
internally balanced to match the scene size. In
animations,however,ifmovingobjectscausea
large change in the scene extents (or if objects are
unhidden, and so on), the normalized bias value
might become inappropriate, causing shadows
toflickerordisappear. Ifthishappens,turnon
AbsoluteMapBias. YouwillhavetosettheBias
control to a value appropriate for the scene. As a
rule of thumb, t ry a Bias value that is the distance
between the light and the target object, divided
by 100.
2-Sided Sha dows—When on, backfaces are not
ignored when calculating shadows. Objects seen
from the inside are not lit by lights from the
outside. When off, backfaces are ignored, which
can cause outside lights to illuminate object
interiors. Default=on.
The faces inside the sliced sphere do not cast shadows if 2-Sided
Shadows is not selec ted.
Came ras
Create panel > Cameras
Create menu > Cameras
Cameras present a scene from a particular point of
view. Camera objects simulate stil l-im age, motion
picture, or video cameras in the real world.
With a Camera v iewport (page 3–745) you can
adjust the camera as if you were looking through
its lens. Camera viewports c a n be useful for
editing geometry as well as setting up a scene for
rendering. Multiple cameras can give different
views of the same scene.
The Camera Correction modifier (page 2–1392) lets
youcorrectacameraviewto2-pointperspective,
in which vertical lines remain vertical.
If you want to animate the point of view, you can
createacameraandanimateitsposition. For
example, you might want to fly over a landscape or
walk through a building. You can anim ate other