I have already added wiggle(5,6) to the expression boxes of all the layers, which is making the oval shapes wiggle with an amplitude of 5 on the x axis and 6 on the yaxis. If I am going to create 4 oval shapes in the composition, and I would like them to rotate and wiggle at the same time with the same values, without adding any keyframes, I will use an Angle Control from Effect -> Expression Controls -> Angle Control, and I will add it to the newly created null object on top of all my layers. Wiggle( time,time ) applied to the position, means that the frequency and amplitude will increase over time, frame by frame, creating an earthquake effect. Y ou can also use expressions inside expressions: Adding the time expression to the opacity for example, modifies this property as the footage plays, frame by frame. T he time expression just expresses the time in seconds. For example, we can write an expression for position using the index: ,position,index*5] which means that x and y are normal, and then the z position is controlled by the index times 5. It's good for creating 3d ensembles and patterns. I f you duplicate the layer, it creates a duplicate in z space. For example, we can write an expression for position using the index: ,position,index*5] which means that x and y are normal, and then the z positionis controlled by the index times 5.

If the layer is moved at the bottom, then the value would be the number of this last layer. If the number of the layer is 3, then the index expressions added on a property of that layer returns avalue of 3. The index expression just gives you the number of the layer. The random expression generates random values, like for example random(0,720), which randomizes the property of the layer (position, scale, rotation etc) between 0 and 720 every single frame. There are a lot of other useful expressions that we could use to make work a lot easier, such as the random, the index, and the time expressions.

Opacity wiggle expression after effects