TECH TIPS
Create Your Own 3-D Universe
Virtual Scene Building with After Effects 5
by Ben Bardens
Without question, Adobe’s After Effects has long been one of
the best compositing applications around. Its introduction sparked
a revolution in how graphics and special effects are produced, giving
artists the ability to composite right on the desktop, with all the
capabilities of a camera stand.
AE is not unlike Photoshop in its layer-based scheme, making it easy
to composite footage from various sources. But ever since version
5 of the software, AE has included an often overlooked, yet rich,
3-D feature set that elevates its compositing capabilities from camera
stand to full-on virtual scene building.
Adobe has continued to refine these features, and with each new version they get better. But 3-D is a lot different than 2-D, and without any formal 3-D training or previous experience it can be a little daunting when first starting out. In this issue’s tutorial, we’ll continue our basic training and introduce some of these powerful 3-D capabilities.
Download the tutorial files from http://www.barkanimation.com/guild/17.zip.
Tutorial
Create a New Project.
Create a New Folder by clicking the little folder button at the bottom
of the Project window.
Name the folder “photos.”
Go back to the desktop and open up the folder called “photos”
within the “source” directory.
Select all the photos in the folder on your desktop, and drag them
on top of the “photos” folder within the Project window
and release.
In the Project window, expand the “photos” folder and
select all the files by clicking and dragging to highlight them all.
Drag all of the selected files on top of the New Composition button
at the bottom of the Project window and release.
In the New Composition from Selection dialog box that appears, choose
Single Composition, and change the Still Duration to 10 seconds. All
the photos are the same size so it doesn’t matter which one
is chosen for the Use Dimensions option. Leave Sequence Layers unchecked
and click OK.
A new composition will open up, with all of the photos placed within
it as layers.
Go to Composition -> Composition Settings. Enter the name “3-D
comp” for the Composition Name and change the frame rate to
30 fps if necessary.
All the layers should still be selected. Click the 3-D switch for
any one of them to enable 3-D compositing for all the layers.
Push the P key on your keyboard to reveal the Position property for
all the layers.
Deselect all the layers by choosing Edit -> Deselect All, or by
clicking anywhere in the gray workspace around the timeline or comp
window.
Size your Composition window as large as you can without obscuring
your Timeline window. Ideally, you want to see as much of both windows
simultaneously as possible.
Zoom out on the composition window so that you can see plenty of the
gray workspace around the frame. You can use the magnification pop-up
at the bottom of the comp window, or you can use the comma key on
your keyboard.
Display rulers by typing Command-R (Mac) or Control-R (PC).
Make sure your Info palette is showing; if it isn’t, type Command-2
(Mac) or Control-2 (PC) to display it.
Drag guidelines out from the ruler on the left side of your Composition
window. As you do so, watch in the Info palette to see the exact pixel
location of your guideline. Drag several guidelines into the composition
from the side, placing them at the following 800 pixel intervals:
-2400, -1600, -800, 0, 800, 1600, 2400.
Do the same thing, this time dragging guidelines from the top rather
than the side, and this time using the following 600 pixel intervals:
-1800, -1200, -600, 0, 600, 1200, 1800.
If you are dragging lines out from the rulers and not seeing guidelines,
go to View -> Show Guides.
Spread the layers out to form a checkerboard pattern, using your guidelines
to align the layers (see figure 1).
Make sure that View -> Snap to Guides is checked.
Use the Tab key on your keyboard to temporarily hide your palettes.
Use the Space bar on your keyboard to toggle the Hand tool to pan
around the comp window as necessary.
If your computer is responding sluggishly as you drag the layers,
temporarily disable screen refresh by pushing the Caps Lock key.
You can check your position values against those pictured (see figure
2). Yours may vary depending on what order you placed the layers into
the checkerboard pattern. Notice that while each layer has a different
X and Y position value, they should all have the same Z position value
of 0.
Select all the layers by typing Command-A (Mac) or Control-A (PC)
and click the stopwatch next to Position for any one of the layers.
A keyframe will appear for each layer at the current time, Time=0.
With the layers all still selected, carefully put your cursor over
the Z value for any one of the layers. Your cursor will change to
a little finger with side-to-side arrows. Click and drag to the right
or left to scrub the Z value and change the layers position along
its Z-axis only (controlling how far away, or close to our virtual
camera lens the layers are). Carefully scrub the Z value to 1800 pixels.
If your computer is responding sluggishly, push the Caps Lock key
to temporarily disable screen refresh.
Move the time marker forward along the timeline to Time=2 seconds.
Carefully scrub the Z value to –300 pixels for any one of the
layers. A second keyframe for each layer will be set.
With all the layers still selected, choose Animation -> Keyframe
Assistant -> Easy Ease In. This will put ease in on each of the
second keyframes for each layer, so that they do not stop moving so
abruptly.
Next, you’ll add a fade-in so that each of the photographs fades
up as it moves forward toward the camera.
Make sure all your layers are selected and push the T key on your
keyboard.
Return to Time=0 and click the stopwatch next to Opacity for any one
of the layers. Click and type in a new value of 0 percent of any one
of the layers.
Drag the time marker to Time=2 seconds and change the Opacity value
of any one of the layers to 100 percent.
While the second keyframes for Opacity are still selected, choose
Animation -> Keyframe Assistant ->
Easy Ease In.
Save your project.
Preview your animation. If necessary to improve performance, you can
drop your preview resolution to half or less from the Resolution pop-up
at the bottom of the Comp window. You can also disable anti-aliasing
for all your selected layers by clicking the Layer Quality switch
for any one of the layers. The Layer Quality switch is the little
forward or back slash line. A smooth line indicates anti-aliasing
is turned on, a blocky line indicates it is turned off. Turning anti-aliasing
off and reducing your preview resolution can greatly improve previewing
performance.
To add interest and alter the timing of the animation, you’ll
spread the keyframes out over six frame intervals and stagger the
action. First, deselect all of your layers.
Move the time marker to Time=0:06.
Select the first layer and drag a marquee around all of the layer’s
keyframes to select them.
Drag just the keyframes (not the pink layer bar) so that the first
keyframes are at the new time.
Hold the Shift key as you drag the keyframes so that they snap to
the time marker’s location.
Move the time marker to Time=0:012.
Select layer number 2 and then select its keyframes and relocate them
to the new time.
Repeat this procedure for each of your layers until the action is
staggered at six frame intervals as is pictured (see figure 3).
Type Command-G (Mac) or Control-G (PC) to bring up the Go To Time
dialog box and then type in +6 to jump forward exactly six frames.
Select all your layers, collapse them and then deselect all.
Save your project.
Click on the Fast Previews button at the bottom of the Comp window
and choose Wireframe. Drag the time marker along the timeline to scrub
through your animation and preview your work.
Make sure your Comp window is active and then choose View -> Hide
Guides and View -> Hide Rulers.
Go back to Time=0 by pushing the Home key on your keyboard or by dragging
the time marker.
Choose Layer -> New -> Camera.
In the Camera dialogue that appears, accept the default 50mm pre-set
settings and click OK.
Choose View -> New View. A second Comp window will appear. Take
a moment to resize your windows and zoom in or out as necessary, so
that you can see as much of both Comp windows and the Timeline window
as your monitor space will allow.
In one of the Comp windows, click on the 3-D View Pop-up and change
it from Active Camera to Top. The resulting view will appear as if
you are looking straight down on the scene. The checkerboard of photos
will look like a dashed line and you will see a wireframe object that
represents the camera layer you just created.
Expand your Camera layer to reveal its properties.
To create the effect of the camera flying into the scene and then
zooming into one of the photographs you’ll animate your camera’s
position.
Note that Camera layers not only have a Position property indicating
where in the scene they are located, but they also have a Point of
Interest property indicating where they are aimed. The Point of Interest
can remain stationary, or it can travel around the scene. If the camera
is moving (the position property is animating) the Point of Interest
can move with the camera, be determined by the camera, or stay locked.
Move the time marker to Time=4 seconds, and type in the following
position value for your camera layer: X=6000, Y=4000, Z=-5000.
By typing in the Position values or scrubbing them numerically, the
Point of Interest will remain at its original location. If you pick
up and move the camera in the Comp window, you will move the Point
Of Interest along with it.
Move the time marker to Time=7 seconds and type in the following position
value for your camera layer: X=360, Y=270, Z=-1000.
To fine-tune the camera’s animation, expand the Speed Graph
by clicking the triangle next to the Position stopwatch.
Drag on the Ease Adjustment handle next to the first keyframe and
adjust the shape of the graph so that it resembles Figure 4.
In your Comp window that is set for Top view, examine the motion path
of the camera (the camera layer must be selected in the Timeline in
order to see the motion path). The path will appear as a straight
line between the two keyframes.
If your motion path appears incomplete, and you do not see a dotted
line connecting both of the keyframes on the path, check the following
setting: After Effects menu -> Preferences -> Display ->
under Motion Path, check All Keyframes. Also, make sure that you are
zoomed out far enough in your Comp window to see the entire scene.
Using the Convert Vertex tool that is hidden behind the Pen tool in
the toolbox, click and drag on one of the Xs that represents a keyframe
on the camera’s motion path. When you drag away from the keyframe
you will get a Bezier handle that will control the curvature of the
motion path. Adjust both keyframes as necessary to create a motion
path similar to what is pictured (see figure 4).
Save and preview your work.
To finish the piece, add the clouds.jpg image at the bottom. Leave
it as a 2-D layer and add a subtle drift and/or scale change to make
it feel alive. Fade in the text.psd file with an in point at Time=7
seconds. Experiment by adding a special effect or glow to the text.
In the reference project, I have put the glow layer in dancing dissolve
mode.
To challenge yourself, add a glow, echo or bevel effect to the photos
that make up the 3-D composite. How would you go about doing this?
Pre-compose all your 3-D layers together, along with the camera, and
then add an effect. The reference2.aep file has a Bevel Alpha filter
applied to the group.
Wrap Up
This tutorial, while it may seem complex at first, only uses a fraction
of the 3-D capabilities that are available. AE also allows for virtual
3-D lighting and material properties for your layers. It is important
to note that without additional software, AE is not a 3-D modeling
application. While you can arrange things in 3-D space to create “objects,”
you can’t actually extrude a layer to give it depth. Think of
AE’s standard 3-D capabilities as being like a virtual set giving
you the ability to combine and arrange footage in a virtual 3-D world-space
complete with cameras and lighting.
Guild member Ben Bardens runs a graphics studio and works as an editor/technical director in the Burbank area. He teaches After Effects and Photoshop at Glendale Community College and can be reached at bbardens@glendale.edu. Find out more about his classes at www.glendale.edu/~bbardens.
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