Premiere is imprinting artifacting on my after effects render

Hi ​@rachelcenter 

Welcome back to the Premiere forums. Thanks for explaining about your issue and including that helpful screenshot. Sorry for any frustrations going on with those artifacts! Since the file looks okay in After Effects and in Premiere’s Source monitor, but shows the artifacts once it is placed on the timeline, this could be an issue with alpha/compositing.

To help us troubleshoot, are you on a Mac (and which macOS) or Windows (Win11 and what driver version/build)?

A few things to try:

1. In Premiere, right click the rendered file in the Project panel and choose Modify > Interpret Footage. Check the Alpha Channel setting there.
2. If possible, render a short test out of After Effects using Straight Alpha instead of Premultiplied Alpha.
3. You can place it over a solid black background and then a solid white background, and let us know if the edge changes.

To further narrow things down, let us know the exact settings you exported from After Effects, can just screenshot the media file properties and what export settings were used.

Hope to help!
Katie