9

Using Transforms to Aim a Camera 1379
Effect drop-down list—
Lets you choose which
multi-pass effect to generate, Depth Of Field (page
2–1383) or Motion Blur (page 2–1386).These
effects are mutually exclusive. D efault=Depth Of
Field.
This list also lets you choose Depth of Field (mental
ray) (page 2–1383), which lets you use the mental
ray renderer’s depth of field effect.
Note: The rollout for the chosen effect appears, by
default, after the Parameters rollout.
Render Effects Per Pass—When on, applies
rendering effects (page 3–218), if any are assigned,
to each pass of the multi-pass effect (depth of field
or motion blur). When off, applies rendering
effects only after the passes that generate the
multi-pass effect. Default=off.
TurningoffRenderEffectsPerPasscanimprove
the render time for multi-pass effects.
Target Distance—With a free camera, sets a point
to use as an invisible target so that you can orbit a
camera around that point. With a target camera,
indicates the distance between the camera and its
target.
Usi ng Tra nsf or ms t o A im a Camer a
You can use transforms to aim a camera and
change its orientation in the scene.
Move (page 1–439) adjusts the posit ion
of the camera object or the position of a target
camera’s target (page 2–1371) .
Because the target is displayed as a small square,
and because it is often in the same area as objects
thatarethesubjectofthecamera,itcanbehard
to select by clicking. Select the camera object,
right-click, then choose Select Target from the
Tools 1 (upper-left) quadrant of the quad menu.
Yo u c a n a l s o c h o o s e C a m e r a s f r o m t h e S e l e c t i o n
Filterslistonthetoolbar,andthenclickthetarget.
Rotate (page 1–439) adjusts the orientation
of the camera object. This transform is most useful
with free cameras (page 2–1370).
You can’t rotate a Target camera about its local X
and Y axes, b ecause it is constrained to aim at its
target. Use Move to move the camera or its target.
Also, if you rotate a Target c amera to a nearly
vertical position, either up or down, the program
mustfliptheCameraviewtopreventtheup-vector
from becoming undefined. If you need a camera
to look vertically upward or downward, use a Free
camera.
InaCameraviewport,youcanalsousethe
navigation buttons (page 3–745) to adjust the
camera interactively. Some navigation buttons,
suchasDollyandOrbitactuallymovethecamera
or its target.
Usin g Clippi ng Pl anes to Ex clude
Geometr y
Clipping planes let you exclude some of a scene’s
geometryandvieworrenderonlycertainportions
of the scene. Each camera object has a near and
a far clipping plane. Objects closer than the near
clipping plane or farther than the far clipping
plane are invisible to the camera.
Clipping planes are useful for rendering selected
portions of a scene that has a lot of complex
geometry. They can also help you create cuta way
views.