Work flow question: Person drawing on wall
by Chris Detjen on Jan 12, 2010 at 9:03:59 pm
I am looking for tips on a solid work flow to create an effect that seems like it might be basic enough to fit in this forum:
Description of effect:
Background is a wall with motion video. A person walks to that wall and draws a few simple shapes and lines with a pen. The person's strokes appear as white lines over the video wall. That person exits frame and another person enters and adds to the drawing and then exits, this repeats until the full drawing is revealed on the wall. The drawing created by the people needs to closely match an image already created (simply a series of boxes interconnected).
It seems to call for some compositing and was curious if someone had a good method so the image that people will "draw" on the wall will actually look like the actual drawing they are outlining.
I thought having the actual full-sized image drawn onto the green screen with thin, subtle white or light green lines. That would give the actors visual reference where to run the pen. We'd then key out the background and create the foreground plate--the people, add the background plate--video wall, and then animate a mask to reveal the lines of the image that the people made.
Re: Work flow question: Person drawing on wall by Dave LaRonde on Jan 12, 2010 at 9:50:09 pm
That's how I'd do it.
It will be a VERY tricky key to pull: both the lighting and the slightly-different-colored outline are crucial. Before the Big Shoot Day, I STRONGLY recommend running tests.
Something else to consider: HDV flat-out sucks at chroma keying. But if you have such a camera, and it has either an HD-SDI or HDMI output on it, you can run it into your capture card and capture the video in full 1920x1080, with MUCH better color resolution, resulting in a MUCH better and easier-to-pull chroma key.
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