- Jun 18, 2009
Animating in the Timeline
The Timeline in After Effects gives you access to several key animation parameters. You can visually access Transform properties (such as Rotation and Position) as well as animate effects. The After Effects Timeline is powerful but offers a refined interface to make it easy to get things done.
Before you can animate items, you need to add them to the composition (by dragging either the Composition panel or the Timeline panel). The stacking order of layers in the Timeline matters when you’re working in 2D space. Layers are stacked from bottom to top (as in Flash or Photoshop).
- Click the disclosure triangle next to each of the Sources folders so you can see all the files contained within.
- Drag the following elements into the Timeline (be sure to drag in this order). Place each new layer on top of the previous in the Timeline.
- logo start (composition)
The Timeline should contain six layers and match the following figure.
When working with layers in the Timeline panel, you’ll often need to adjust their start and end points. The beginning of a layer is called its In point and the end of a layer is called its Out point. The duration of a layer is defined as the span between a layer’s In and Out points.
When you trim a layer in After Effects, you modify its In or Out point (and therefore its duration). Let’s explore trimming as well as adjust the In point for a layer.
- Select the layer Chart.swf in the Timeline.
- Press the End key or drag the Current Time Indicator to the end of the composition.
- To make trimming easier, you can view the In and Out point controls. Right-click on the Source Name header and choose Columns > In. Repeat and choose Columns > Out.
- Click the Out point text for the Chart.swf layer and enter 19:29 in the pop-up menu.
- The layer’s In and Out points have changed. This is not desired because the start of the animated SWF file now occurs before 0;00;00;00. While it may seem confusing, it is possible to set layers to occur before the first visible frame. This allows effects to pre-roll or start animating before they are visible. Choose Edit > Undo to reposition the layer.
- To trim a layer, use the keyboard shortcuts. Press Option +] (Alt+]) to modify the layer’s Out point.
- Although you trimmed the Chart.swf layer, you need to extend the bg.mov layer. Unfortunately, this layer is a movie file with a duration of only 10 seconds. Before the layer can be trimmed, it needs to be looped. Select the bg.mov file in the Project panel.
- Choose File > Interpret Footage > Main. The Interpret Footage dialog opens. In the Other Options area, enter a value of Loop: 2 Times. This particular footage is a looping background, which means it has been prepared to have identical first frames and last frames. Click OK to store the change. This process is very specialized, but many movie files sold by stock footage companies are prepared this way.
- Select the file bg.mov in the Timeline. Press Option +] (Alt+]) to modify the layer’s Out point (if you need to trim an In point, use the [ key).
- Drag the Current Time Indicator to 1:15 in the Timeline.
- Select the layer logo start. Press the [ key to move the selected layer’s In point. By using just the bracket key, the layer is moved but not trimmed.
- Choose File > Save to save your work so far.
As your Timeline gets more and more full, it is a good idea to consider using pre-compositions. A pre-composition (or pre-comp) is essentially one composition nested inside another. There are many reasons to use a pre-comp; they range from technical decisions (such as forcing certain effects to render first) to organizational decisions (making repeated use of an element easier).
- Click the eye icons next to all layers in the Timeline except the bg.mov layer to disable their visibility.
- Select the layer bg.mov in the Timeline.
- Choose Layer > Pre-compose. A new window opens prompting you to specify settings for the pre-composition.
- Enter the name Blue BG into the New composition name field. Select the “Move all attributes into the new composition” option. This option will nest the selected layers inside the new pre-composition. Select the Open New Composition check box. Click OK to create and open the new pre-composition.
- In the Project panel, drag the new pre-comp Blue BG into the Pre-comps folder you created earlier. This helps keep the project organized.
Using Adjustment Layers
An adjustment layer makes it easy to quickly stylize layers in a composition. Using adjustment layers is a useful way to apply effects to one or more layers. Let’s add an adjustment layer to the current pre-composition.
- Choose Layer > New > Adjustment Layer. An adjustment layer is added to the top of the Timeline.
- In the Effects & Presets panel, type Colorama into the search field. The Colorama effect uses a range of colors to colorize the affected layer.
- Drag the Colorama effect onto the adjustment layer. The footage is colorized with the default color map (which is pretty unattractive).
- The Project panel now has the Effect Controls panel docked with it. This panel offers precise control over the applied effect. Click the disclosure triangle next to Output Cycle to view the applied color map.
- Click the Use Preset Palette menu and experiment with the different options in the list. The circle indicates the color that is being applied to the image. The colors are mapped based on the luminance value of the footage.
- Let’s use a saved preset for the animation. The use of presets allows you to store settings for use again in the future or to exchange them with another user. Choose Animation > Apply Animation Preset.
- A new dialog opens so you can navigate to the preset. Open the Chapter_01 Project Files folder.
- Select the file Sky_Blue.ffx and click Open. The new settings for the effect are applied.
- Select the adjustment layer in the Timeline.
- Click the Toggle Switches/Modes button to access blending modes. You can use blending modes to change how two layers interact.
- Change the mode for the adjust- ment layer to Color. The effect is now applied more “gently” based on the original color values in the under-lying footage.
- Close the pre-composition by choosing File > Close. The original Bumper composition is now selected. Choose File > Save to save your work so far.
After Effects offers five Transform properties for layers. These properties can be adjusted to affect the appearance of a layer or keyframed to create animation:
- Anchor Point (A)
- Position (P)
- Rotation (R)
- Scale (S)
- Opacity (T)
Let’s apply transformations to several layers to create changes to the composition’s appearance.
- Select the Bumper Timeline, then select the Chart.swf layer in the Timeline and click the eye icon to enable its visibility.
- Press S to access the Scale properties for the layer. Enter a value of 125% to enlarge the layer and press Return (Enter).
- The SWF layer is a vector file, which means it can be scaled above 100%. You must enable a switch to preserve vector scaling and quality; otherwise, the image gets pixilated. Click the Toggle Switches and Modes button at the bottom of the Timeline, then click the Continuous Rasterize switch for the chart layer (click in the empty space for the layer in the “sun” column).
- Press T to control the Opacity of the layer, enter 40%, and press Return (Enter).
- Press P to control its Position, and enter 500 into the Y value (the second number) to lower the chart along the Y-axis.
- Select the skyline.ai layer and click the eye icon to enable its visibility.
- Press S for Scale, hold down the Shift key, and press P for Position. Scale the layer to 65%.
- Drag the Y value for the Position property until the skyline is aligned with the bottom of the Composition panel. If needed, be sure to choose Fit from the Magnification ratio pop-up menu.
- Set the X value for the Position property to 1350 and the Y value to 450.
- Select the layer clouds.psd in the Timeline and click the eye icon to enable its visibility.
- Press S to access the Scale properties for the layer. Enter a value of 80% and press Return (Enter).
- Let’s animate the layer so the clouds appear to drift. Hold down the Shift key and press A to add the Anchor Point controls.
- Switch the cloud.psd layer to the Hard Light blending mode (if necessary, click the Toggle Switches/Modes button at the bottom of the Timeline).
- Move the Current Time Indicator to the start of the Timeline.
If you want to animate a Transform property, you can use keyframes. The word keyframe has a long history in animation, dating back to the time of early hand-drawn animation where the lead animator would draw the major poses (or keyframes) and assistants would fill in the drawings in between. In modern computer animation, you set the keyframes and the computer fills in the rest (called interpolation or tweening).
- Make sure the layer cloud.psd is selected.
- Click the stopwatch next to Anchor Point to enable keyframing.
- Enter a value of 850 into the X field for Anchor Point.
- Press End to go to the end of the composition.
- Enter a value of 1750 into the X field for Anchor Point. A new keyframe is added to the layer.
- Click the RAM Preview button to see the results so far. Then choose File > Save to save your work.
After Effects makes it easy to synchronize layers by establishing parent-child relationships. When you employ parenting, changes you make to one layer affect another. An easy way to think of parenting is to think of the relationship between your body and arms. When you move your body by turning at the waist, this causes your arms to turn. However, your arms can also move on their own (but they must still follow your body). The rest of the relationship persists throughout your arm: just think of the dependencies between the elbow, the wrist, and the individual fingers on your hand.
- Move the Current Time Indicator to the start of the Timeline and select the layer skyline.ai.
- In the Parent column, click the pickwhip and drag it to the layer clouds.psd. The new name appears in the parent column for the skyline.ai layer.
- Click the RAM Preview button to see the results so far. The skyline layer now moves with the clouds layer and pans to the right. Then choose File > Save to save your work.