Blackmagic Forum

I hate to show my ignorance but I dove into a fusion setup that is a little over my head.
Here's the node diagram and spline inspector:
As you can see the DeltaKeyer (with the help of a CleanPlate) is removing the green but the microphone was showing so I added a spline and a merge node to make the microphone transparent. But, as you can see, the hoped-for black and gray checkerboard inside the spline on the far right (output) display is not there. Instead, you can see the microphone (that was supposed to be checkerboarded out) surrounded by the spline outline. How do I make the microphone transparent (checkerboarded)? (Yes, I was also planning on adding another spline to make the wedge of beige light at the top of the green area go away too but I got bogged down on the first spline.)
Here's the inspector for the merge node:


And here's is how it looks from the edit page:

How do I make the microphone and beige wedge "checkerboard" to transparency?
Thank you!
John

I am not a Fusion expert, but I can offer some suggestions to make future work easier.

Have a larger green panel, and make sure the mic isn't anywhere in the shot.

Thank you for that advice. That's what I've been doing but at some point, if I'm going to be good with Davinci, I need to learn how to make things disappear even in moderately complex node maps. Can anybody explain what changes are needed in that node map shown above?
Thanks!
John

Connect your mask to the garbage matte input of DeltaKeyer. Or add a MatteControl node downstream and connect mask to garbage matte input of that.

Connecting a mask to a merge doesn't "mask" the image the way you would think, and it doesn't allow masking the image the way it would in some other softwares either (stencil for alpha from fg or out for alpha from bg mode). Some Fusion specialist can elaborate on this topic more in the context of how Fusion specifically handles shapes and image data.