Split Screen Mask

Creating a Split Screen using a Mask

There are lots of ways of doing split screen in Sony Vegas. Probably the way most people do it is with the Pan/Crop tool. This makes sense if you don’t need to move the image around after it is cropped (i.e., the object you want to crop will remain at the same place on the screen after the crop). But what if you have two people who are in the center of the screen and you want them to be side-by-side? You could use Pan/Crop and then use Track Motion to move them to one side but there is an easier way using the Mask tool in Pan/Crop.

Here is the problem: I have two subjects that are shot on a green screen. When shot they were standing dead center but in the composited shot I want them side by side. Here are the original clips:

Let’s see how we can make a Mask and use Pan/Crop to place these clips side-by-side:

1. Place each clip on a separate track above each other.
   
   
    
2. Select the Pan/Crop tool for the top track.
   
   
    
3. In Pan/Crop enable the Mask tool by placing a check mark next to the Mask track.
   
   
    
4. Draw a mask around your subject. If you feel that your lines aren’t straight, just use the X, Y parameters under Position to ensure that the pairs of points are using the same values.
   
   
    
5. Click on the Position track (1) to highlight it and reposition the frame [F] to the right side of the screen (2). (hint: Pan/Crop works backwards to by pushing the Frame to the right it moves the image left.)
   
   
    
6. Close the Pan/Crop tool and notice that you now have one of your subjects in place in the Vegas Preview. We're half way there.
   
   
    
7. Repeat steps 2 through 5 for the second track to make a mask around the second subject.
   
   
    
8. Select the Position track and move the frame to the left side of the screen which moves your subject to the right in the frame.
   
   
    
9. Check your Vegas Preview window and tweak the Pan/Crop movement until you achieve the desired effect.
   
   

If we were to really sell the illusion of these two subjects being side-by-side at the same time I would use a Chroma Key filter to key out the green backgrounds of each track individually and place a third track under them with a common background. I would probably also use Pan/Crop to zoom out a bit to make the subjects smaller and get them closer in the frame. Something like the shot below:

But we’ll leave that for another tutorial. ;-)

Happy Editing,