What is the main purpose of using an Adjustment Layer in After Effects?

The main purpose of using an Adjustment Layer in After Effects is to add effects that apply to all layers beneath it in the layer hierarchy. When an Adjustment Layer is created, any effects applied to it will have an impact on all the layers that are positioned below it. This allows for efficient modifications to multiple layers at once, enabling changes such as color correction, blurring, or applying any other effects without the need to individually apply those effects to each layer.

This method promotes a non-destructive workflow, as it keeps the original layers unaffected while utilizing the Adjustment Layer for the applied effects. Using an Adjustment Layer streamlines the process, facilitating creative adjustments and achieving complex visual effects more effectively.

While isolating the effects applied to layers below and creating a background layer could seem relevant, those actions do not encompass the breadth of utility that Adjustment Layers provide. Additionally, rendering speeds are influenced by various factors but are not primarily determined by the use of an Adjustment Layer.