 | Removing a person from a moving shot
on May 29, 2010 at 9:34:37 am |
Hi all,
I'm currently working on some very interesting VFX shots. One of them includes a scene where a person spontaneously combusts. In other words, they explode for no apparent reason. This would be relatively easy to do if it were a locked off shot, but it's done handheld. So basically, I've been killing myself trying to track it in AE and trying to find a way to fill in the background after I've removed the actor with some basic rotoscoping..
The shot is like this: actor walks around a bit in the frame. He 'explodes' and then quickly runs out of the frame. Then there is a few seconds of a handheld 'cleanplate' which doesn't do much for me because it's a moving shot. Oh, and bonus points, because I can't cut to a point when the actor is already gone because he throws all of the things he was carrying in an explosive fashion.
I heard that mocha or something similar can help, but I'm not sure. Anyone know how I can accomplish this?
 | Re: Removing a person from a moving shot on May 29, 2010 at 11:11:22 pm |
Check out this tutorial on that very subject. There are some other videos that may be of interest on the right side of the page.
-E
 | Re: Removing a person from a moving shot on May 31, 2010 at 6:57:30 pm |
I would go with mocha.
But I can think of one other way then mocha to do this I call it "the cheap way".
If I got it right, You should be able to do the following:
Start with:
The footage with no actor. Make a freeze frame.
Continue with:
Track the footage with the actor. Set the tracking to the footage with no actor (the freeze frame)
After that:
Mask the actor (guess You have to animate the mask to get it to look good).
When that is done:
Subtract the mask so You can see the freeze frame.
The goal:
By masking the actor away You should see the freeze frame, the freeze frame should have the same shakes as the footage with the actor.
Then You can:
For example make it look better by pre-compose and duplicate the composition and add some gaussian blur and lower the opacity. Or something.. I'm no pro.