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Animating Cameras 1381
If the image’s hor izon and the camera horizon
don’t match, you have to offset the image,
perhaps by using a paint program.
3. Use Orbit (page 3–749) to move the
camera until the perspective of the scene
roughly matches that of the still image.
4. Adjust the camera’s perspective (page
3–747) to fine-tune the perspective match.
5. Use Move (page 1–439) with the camera
or target to position the scene against the
background.
If you raise or lower the camera, raise or lower
thetargetbyanequalamount,inordertokeep
them level and maintain the horizon.
Yo u c a n a l s o u s e t h e Camera Match utility (page
2–1387) to match the perspective of a camera
to a photograph. You will need accurate scene
measurements to do so.
Animating Cameras
Youanimateacamerabyusingtransformsor
changing its creation parameters in different
keyframes while the Set Key or Auto Key button is
on. The program interpolates camera transforms
and par ameter values between keyframes, as it
does for object geometry.
See Auto Key Animation Mode (page 3–717) and
Track View (page 2–501) for further descriptions
of animation. This topic summarizes some
possibilities and suggests some techniques.
In general, it’s best to use a free camera (page
2–1370) w hen the camera is to move within the
scene; use a target camera (page 2–1371) when
camera position is fixed.
MovingaCameraAlongaPath
Havingacamerafollowapathisacommonway
to create architectura l walkthroughs, roller coaster
rides, and so on.
•Ifthecameramustbankortiltclosetothe
vertical (as on a roller coaster), use a free
camera. Assign the Path constraint (page 2–398)
directly to the c amera object. The camer a
follows the path, and you ca n adjust its point
of view by adding pans or rotate transforms.
This is comparable to filming with a hand-held
camera.
• For a target camera, link both the c amera and
its target to a dummy object (page 2–16),then
assign the p ath constraint to the dummy object.
This is comparable to mounting the camera
on a tripod on a dolly. It is easier to manage
than having, for example, sep ar ate paths for the
camera and its target.
Following a M oving Object
Yo u c a n u s e a LookAt constraint (page 2–406) to
have the camera automatically follow a moving
object.
• The LookAt constraint makes the object replace
the camer a’s target.
If the camera is a target camera, its prev ious
target is ignored.
If the camera is a free camera, it effectively
becomes a target camera. While the Lo okAt
constraint assignment is in effect, the free
camera cannot rotate around its local X and Y
axes, and can’t be aimed vertical ly b ecause of
the up-vector constraint.
•Analternativeistolink (page 2–422) atarget
camera’s target to the object.
Pann ing
You can animate the pan of any camera very easily
by following these steps: