Fill mask with green?

frederick-wise wrote on 7/29/2010, 10:19 PM
I just got a green screen but unfortunately it isn't wide enough to fully handle my 16:9 ratio camcorder so there is about 2 feet of non-green screen on each edge of my video clip. I was thinking I could mask the edges and then fill it with green using the eyedropper tool and then rerendering the video clip with green stretching from edge to edge. So far I've made a mask but don't see any way of filling the masked area with green. Does anyone know if this can be done and how to do it? I've also fooled around with the cookie cutter and that seems like it may work. Thanx

PS zooming in won't work because that would eleiminate the full body shots, head to toe, of my talent that I need to preserve.

Comments

PeterWright wrote on 7/29/2010, 10:41 PM
Instead of filling the edges with green then masking out with Chroma, you can mask them out directly using Pan/Crop (Unclick the Lock Aspect Ratio Icon) or, for a more complex shape, the Bezier tool within P/C.
Rory Cooper wrote on 7/29/2010, 10:47 PM
JV1

Place a flat green solid color behind after you have masked the outside area of your green screen and use eyedropper to match screen

What I am wondering is why would you go through all this trouble if its keyed out and masked out then it’s done why put the green back
Rather render it as a png sequence or RGBA clip
frederick-wise wrote on 8/1/2010, 6:59 PM
Thanx for the reply but I need more assistance please. I masked out the edges using the pan/crop tool and now they are black. So now I have my actor in front of the green screen but the edges are black. I can't figure out the next steps to turn the black edges green. Please advise. Thanx.

PS I couldn't find any references to rendering as a png or RBGA format.
PeterWright wrote on 8/1/2010, 9:16 PM
If I understand what you are trying to do, you don't need to make the edges green.
The fact that they are black suggests they are now transparent, ready to show whatever background you want to use behind the actor.

By applying Chrome Key to the green screen, that too will become transparent, so you will now have what green screen is usually used for - the ability to remove the background around the actor and replace it with whatever you want to put there (on a lower track).
farss wrote on 8/2/2010, 6:53 AM
The term that I think is missing here is "garbage matte".
From Wikipedia:

"A "garbage matte" is often hand-drawn, sometimes very quickly made, and can be used to exclude parts of an image that another process, such as bluescreen, would not remove. The name stems from the fact that the matte removes "garbage" from the procedurally produced image. This "garbage" might include a rig that is holding a model or the lighting grid above the top edge of the bluescreen. Garbage mattes can also be used to include parts of the image that might otherwise have been removed by the bluescreen, such as too much blue reflecting on a shiny model ("blue spill")."

In general one should use a garbage matte to remove any section of the video that does not have to be keyed. This simplifies the task of keying. A static mask is usually enough and can be very quickly created in Vegas as outlined above. The actual chroma key is then used to handle the parts of the frame that would be too tedious to mask out by hand e.g. moving limbs, hair etc.

Bob.
frederick-wise wrote on 8/5/2010, 12:21 PM
Thanx for all of the help folks. I figured out the masking way to do it by watching some how-to videos on youtube and now my little crisis is resolved.