Link Properties Across Layers with Expression Pick Whip

The Expression Pick Whip eliminates manual duplication. Link a slider on a control layer to properties across your entire composition — change one value, everything updates.

Basic Linking

1. Alt+click the stopwatch on the property you want to drive
2. The expression field opens
3. Drag the Pick Whip (spiral icon) to the source property on another layer
4. Release — the expression auto-populates
5. The linked property now mirrors the source

Slider Control Pattern

1. Create a Null Object, name it "Controls"
2. Add Effect > Expression Controls > Slider Control
3. Name it descriptively ("Background Opacity", "Text Size", "Animation Speed")
4. Pick Whip other layers' properties to this slider
5. Now you have one control surface for your entire comp

Color Control Pattern

Same concept with Color Control. Add a Color Control effect to your control null, then link Fill colors, text colors, and shape colors across your comp. Update the brand color once — every element updates. We build every client template at Southbound Studios with a control layer system so any editor can re-brand in seconds.

Math in Expressions

After linking, you can modify the expression: multiply by 2 to double the value, add an offset, or use conditional logic. Example: thisComp.layer("Controls").effect("Size")("Slider") * 1.5 links to the slider but scales the result by 1.5x.