What do you need to do to create realistic shadows for your 3D layers?

Creating realistic shadows for 3D layers in Adobe After Effects requires the use of lights in your composition. When you add lights, you can enable shadows and adjust their properties, such as darkness, diffusion, and distance. This allows the shadows to interact with the 3D layers in a way that mimics how light behaves in the real world, adding depth and realism to your scenes.

By properly configuring the light sources, you can control how shadows fall and their appearance based on the light angle, which greatly enhances the visual fidelity of the composition. Without lights, 3D layers in After Effects remain largely flat and don't exhibit the dramatic effects of shadowing that real-world objects do.

Other options, like decreasing layer opacity, increasing brightness, or applying motion blur, do not directly contribute to the creation of realistic shadows. Instead, they serve to modify the appearance of a layer without affecting how light and shadow interact in a 3D space. Thus, utilizing lights effectively is essential for achieving the desired shadow effects in your 3D compositions.