black line around transparent object when exported from after effects

It's likely an issue with how the transparency is being handled. Even though you're exporting in Apple ProRes 4444 with Straight (Unmatted) Alpha, some programs might not interpret the transparency correctly. Try switching to Premultiplied (Matted) instead and see if that removes the black edges. Also, check your composition to make sure there's no subtle stroke or shadow effect applied to your shape. If you're viewing the exported file in another software, it might be displaying the transparency incorrectly. To fix this, check the Alpha Channel Interpretation settings in the program you're using to view or edit the video. If the issue still happens, try exporting as a PNG sequence instead of a video file to see if the edges are cleaner.

Hi kathryno,

That's not ideal. I just tried that on my end with the settings you mentioned. However, I don't see any black line around the white rectangle. What version of After Effects are you using? In which application are you previewing it? Can you try importing the exported file in After Effects and checking if you still see the black line? Also, please share a screenshot that shows the problem.

Let me know. Moving this thread from Bugs to Discussions for troubleshooting.