Blurs in Action

I’m trying to fake a blurred reflection in Action but getting stuck with how to achieve it cleanly.

I have a toy robot shot on greenscreen, keyed using MKeyer and fed into Action. In Action i have two copies with one flipped for the reflection. When i add a Blur (using Add Selective). The problem is when i increase the blur, the greenscreen is being pulled back.

Any suggestions how to remedy this?

Multiply the front of your layer and your alpha channel before feeding it into action. Hence the term “premultiplied”

An interpolated pixelspread before feeding it into action often also works great, but could reduce some borderdetails

thanks both for the suggestions.

using the Premult helps a lot but it does result in a black blurred edge instead of green.
Tried a pixelspread as you described and that seems to be working.



For the premult to work, your surface should be set to “premult” as well under the surface properties. But I agree pixelspread works without this additional step.

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