Blurs in Action

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1

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?

Screenshot 2022-07-07 at 12.10.45
Screenshot 2022-07-07 at 12.10.451129×792 39.1 KB

2

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

3

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

4

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.

thanks
adam

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5

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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