How to Link Properties Using Pick Whip in After Effects

The pick whip in Adobe After Effects is a visual tool that automates the creation of expressions, allowing you to link the property of one layer to that of another without writing code manually. By connecting properties such as Position, Scale, Rotation, or custom effect sliders, you ensure that any change made to the source property automatically drives the connected target property. This guide covers how to locate the property pick whip, connect values between layers, and make simple adjustments to the generated link.

1. Distinguish Between the Two Pick Whips

After Effects contains two distinct pick whip tools:

  • The Layer Pick Whip (Parenting): Located in the Timeline panel under the "Parent & Link" column. This links entire layer transforms to another layer.
  • The Property Pick Whip: Located directly next to an individual property's stopwatch or expression controls. This is the tool required to link specific values (such as connecting Layer A's Opacity to Layer B's Rotation).
  1. Select the layer containing the property you want to control (the target property).
  2. Press the corresponding shortcut key to reveal the property (e.g., P for Position, S for Scale, R for Rotation, T for Opacity), or twirl open the layer's transform options.
  3. Select the layer containing the driver property (the source property) and reveal its properties as well.

3. Enable Expressions on the Target Property

  1. Hold down Alt (Windows) or Option (macOS) and click the stopwatch icon next to the target property.
  2. The property value turns red, an expression text box opens in the timeline, and four expression-related icons appear directly beneath or next to the property name.

4. Drag the Property Pick Whip

  1. Locate the swirl-shaped icon (the property pick whip) among the expression controls for the target property.
  2. Click and hold the pick whip icon, then drag the line that appears toward the source property's name or value.
  3. Once the source property is highlighted, release the mouse button.
  4. Click anywhere outside the expression field or press the numeric keypad's Enter key to commit the expression.

5. Modifying the Connection (Optional)

Once linked, the target property updates in real time whenever the source property changes. To alter how the target responds, you can append simple mathematical operators directly to the end of the generated expression:

  • Invert direction: Place a minus sign (-) at the very beginning of the expression string.
  • Multiply value: Add * 2 at the end to double the output value.
  • Divide value: Add / 2 at the end to halve the output value.
  • Add an offset: Add + 50 at the end to consistently offset the value.

To break the link, simply Alt-click (Windows) or Option-click (macOS) the target property's stopwatch again to remove the expression.