5. Reposition the anchor - Double click the left wing layer in the timeline to open it in the paint layer. Use the selection tool to move the cross-hair anchor point to the shoulder part of the wing. Repeat this for the right wing, then close both paint windows. Once back in the composition you will have to reposition the wings.
6. Setting keyframes - Select the Left Wing. Press R to bring out the rotation property. With the playback head at the beginning, click on the stopwatch icon to enable keyframes. Set the rotation to be – 28. Move forward seven frames and set the rotation to 28. Move to the end of the first second and set the rotation back at – 28.
7. Looping with expressions - To have the wing flap throughout we could keep setting manually, but this is time consuming, as would copying and pasting them. Instead we shall use an Expression, After Effects’ built in scripting language. Alt click on the Rotation stopwatch to open the Expressions line and type in exactly: loopOut(type = “cycle”). Repeat this for the right wing.
8. Scale a composition - Close the Robin composition in the timeline then drag it from the project palette into the main composition. Scale the Robin down to size and position just off screen. Press P to reveal the position property. Switch on keyframing, move the playback head forward a second and drag the robin to the ground so he flies in.
9. Importing the action - Record your live action and import. Our figure is miming pulling the lever against a blue background. Place your live action on the timeline. The Effect>Keying>Keylight 2.1 filter, now incorporated with After Effects, removes the blue background or you could use the Roto Brush. As soon as an effect is applied its controls appear in the Effects Control Palette.
10. Keying the action - In the Keylight controls use the eyedropper to select the blue background. The screen gain slider sets the opacity of the background while the clip black and clip white sliders remove shadows. The lever, like the robin wings, needs its anchor point moving to the bottom of the lever. This is then animated in synch with the action.