Tutorial 4: Creating a Virtual set with a Foreground from a Digital Snapshot
Making your own virtual sets doesn’t have to be difficult. In fact any picture, any image, can be transformed in a matter of minutes into a nice virtual set. In this example we’ll not only use a digital photograph as a set, we’ll create a foreground element from the same photo using a paint program.
Snap your picture from roughly the same height and angle that your green screen footage is shot at. In this case, I looked for a suitable backdrop for Suzy’s “Walk-in Left” clip that comes included with ULTRA.
I shot this picture of the doorway to the Serious Magic conference room with a cheap digital camera, and did a little tweaking in Photoshop to adjust the levels a bit. (Keep in mind that you could use any image manipulation tool to do the steps described in this tutorial.) I also spruced up the blank wall with the cover art from the ULTRA box. I saved a copy of the image, and called it BACKGROUND.
Then, using the magic wand and lasso tools, I selected the wall in the image, cut that to a new layer, and deleted the rest of the image. I saved the result to a format that supports an Alpha Channel, like PNG or 32-bit BMP. I called this version FOREGROUND.
In ULTRA, I brought in Suzy’s “Wide, walk-in Left” input clip. Then, I dragged in the Background image to the background icon, and I dragged the foreground image and dropped it into the Overlay icon.
After keying Suzy and cropping the right side of the clip, I used the control in the scene tab to position her walking through the doorway. I also used the post-processing color correction to match Suzy into the shot better.
Once I had the positioning set up, I realized that her hand gestures were interfering with “selling the shot.” To look realistic, her hand should gesture in front of the door frame, not behind it. The solution? Split the clip in half, and save it as two separate clips.
I trimmed the end of the input clip to 3 seconds, which is where Suzy comes through the doorway. I saved this clip out as “Part One.”
Then, I reset the end point, and set the in point of her clip to 3.01 seconds (the moment she should be “through the doorway,”) and removed the Overlay (right-click on the Overlay icon.) I saved this clip out as Part 2.
To get one continuous clip, I dragged both finished AVI files into an editing application, made sure both clips were next to each other, and saved out the result.