Step
1
Create
your helper object. Make sure you place it in front of the eyes,
a foot or two away from the face. The exact distance doesn't matter,
but it makes it easier to animate if it's out in front of the
head somewhat. Which kind of helper to create is a personal preference.
You can use geometry, splines, or Max's ready made helpers. I'm
using the Point helper here.

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Step
2
Go
to the Motion panel, expand the Assign Controller menu,
select Rotation, and click on the Assign Controller button
(the question mark).

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Step
3
Select
LookAt Constraint from the list.

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Step
4
Scroll
down the panel and select the Add Orientation Target button,
and then select the helper object as the target. The eye might rotate
after you select the target, but this is normal. Go to the next
step to fix this.

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Step
5
Scroll
down further and check the Keep Initial Offset box. By the
way, if you get into the habit of creating all your objects in the
same viewport you won't have to do this step. But I tend to create
new objects in whatever viewport I happen to be working in at the
time, so I'm glad this check box is available.
There
are many other options available with this controller, but you shouldn't
need to change any of them to make this work. If you like a clean
viewport, however, you might want to change the Viewline that
is created when you use this controller. You can either uncheck
the Viewline Length Absolute box, or change the Viewline
Length to 0 to get rid of it completely.

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Step
6
Now
go back to step 2 and repeat for the other eye. Once they're both
set up you can move the helper object around the scene and the eyes
will follow it wherever it goes. You'll probably want to link the
helper object to the head so that the eyes don't move until you
want them to.

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This
technique is pretty straight forward to set up and is easy to animate
with.
Here's
some other things you can do with this setup:
Change the Transform Controller to Link Constraint and
then link the helper object to different objects in your scene. This
way you can have the character's eyes follow a ball, or some other moving
objects, without having to manually animate the eyes.
You can also achieve the same effect by selecting the ball, or whatever,
as another LookAt Target. You can have many LookAt Targets
for your eyes. Then you would animate the Weight for each
target to have the eyes look at different objects. A weighting of 0
means the eyes don't follow that object at all, and a weighting of 100
means the eyes follow that object exclusively. The drawback to this
approach is that you have to animated the weighting for both eyes individually.
It's much easier to just link the helper object to whichever item you
want the eyes to follow.
Click
here to learn about more advanced techniques..
Click
here to go back to the "Eyes" page...
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