Holdout Off by About 5 pixels

I’m rendering out a simulation of some rocks falling from an alembic import, and the holdout is about 5 pixels off. So I’m getting a black outline in the comp.

How do I fix this?

Hi this likely is caused by EmberGen not having depth of field capabilities in the camera, so the part that is blurred in Blender is rendered solid from EmberGen. If you increase the DoF in the camera in Blender or change the focus point does that address the issue? I have a video that demonstrates a way to get around this here: https://youtu.be/ZSJCD36_YX8?si=Ndid_xnTx1-mukzr&t=1080