Hi
Honestly, I think the best way to achieve this would be to have your video layer as a Plane or Background object within C4D. The renderer can than build more realistic refractions. Alternatively, you can fake this to some extent using the water rendering as a distortion map in AE, which will give you greater control of the final look rather than waiting on C4D’s rendering, but if you want the computer to do the heavy lifting, then export your video layer I reckon.
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