ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Removing a person from a moving shot

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Rob Rhodes
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?

Return to posts index

Erik Waluska
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.


Return to posts index

Viking Jonsson
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.

Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2018 All Rights Reserved