Drop Shadow--AE

This effect adds a shadow that appears behind the clip. The shape of the Drop Shadow is determined by the clip's alpha channel. Unlike most other effects, Drop Shadow can create a shadow outside the bounds of the clip (the dimensions of the clip's source).

Since Drop Shadow uses the alpha channel, it works well with 32-bit footage files from three-dimensional rendering programs and drawing programs that support the alpha channel.

Note: For optimal results, use the Drop Shadow filter on a clip that has an alpha channel and is placed on a superimpose track, with the clip's Transparency set to Alpha Channel. Because Drop Shadow works best when it is the last filter rendered, apply this effect after applying all other filters. You can create a better shadow on clips in motion by applying the Transform or Basic 3D effects prior to applying Drop Shadow instead of using Premiere's Motion command because that command will not be applied to the clip until all the other filters have been applied.

Applying Effects > Video effects included with Premiere > Drop Shadow--AE