Masking Q


I am trying to figure out how to integrate the mask element for the stairs. As you can see the third ball is under the stair and I have the mask ready but unsure where to plug it in. I have provided the script and image for reference.

Thanks everyone.


if you add another Copy-node (after that over below Copy2) to copy the red from the mask into the alpha and a Premult after that…that should do the trick.

hope that’s what you meant :slight_smile:



Would you mind seeing what I did wrong. Attached is a screen cap.


switch the inputs on Copy1 :slight_smile:
what exactly are doing with Copy2? just curious…



Here’s a grab for copy2.


Fixed it. Thanks.


I am now trying to find out how to use the edge blur on intersecting masks. I tried to split up the mask in red and green channel, but its still sharp at the intersection. Now if it’s 1 mask element with shuffled red and green it sort of works but as you can see in the second image it’s picking up the background when blurred.

Please help someone.



Anyone interested. The fix was to change the plus to “mask” after the shuffle. Next change the edge mult setting in edge blur to 10.


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