At The Movies - Chroma Keying.
http://www.studio1productions.com

I believe Forrest Gump, said, “Digital mixers are like a box of chocolates. You never know what you’re going to get.”

I’m often asked, “Where can I pick up some ideas for using my digital video mixer?” I tell them (after they buy my instructional video tapes, of course) to go to the movies.

When you think of special effects on the silver screen, you recall artists like Steven Spielberg or George Lucas because their effects are great and very obvious. However, when the special effects are so brilliantly performed that you don’t even realize that you’ve been fooled, then you’ve experienced fantastic special effects. Such as the case with the hit Forrest Gump.

How did Tom Hanks shake hands with JFK, Lyndon Johnson and Richard Nixon?

How did the floating feather in the opening title sequence float right down to Hanks’ feet?

And how did Gary Senise (“Lt. Dan”) become a double amputee for the remainder of the movie?

Simple: Chroma Key. Or “blue screen” as they refer to in the movie industry.

If you haven’t tried it already, get some old film or new footage, which can easily be black and white. Use this footage as your background footage while you stand in front of your Chroma key blue (or green) wall or backdrop. And on the foreground, or key channel of your Panasonic MX-50, MX-20, AVE-55, Videonics MX-1, MX-PRO or Sony FXE-100, use your digital effects section to turn the video signal of yourself into monochrome (black & white).

Now join Humphery Bogart for a drink in Casablanca. Or climb on the Stagecoach with John Wayne. Or even sit on the loveseat with Marilyn Monroe in Gentlemen Prefer Blondes.

If you want a feather to float right down to your feet, videotape yourself sitting on the bus bench like Forrest Gump and use that footage as your background video. And for your foreground video, attach a feather to a blue thread and dangle it in front of your blue backdrop. Now just watch your video monitor as you lower the threaded feather to your pre-recorded feet.

Body parts can be removed by merely wearing, let’s say, a blue glove while you’re standing in front of your blue backdrop. Blue tights worn on your legs will make them vanish as well. Or, how about attaching a round piece of blue cloth to your chest to give the illusion of a rocket just passing through you.

Just give in to the fact that if you see an effect at the movies that appears too far-fetched to be true, first of all, it is. And second of all, it’s probably Chroma key. Imagination is the key here. So go to the movies. Have some popcorn and get lost and escape from reality created by the movie masters. Then go home and perform the same effects yourself.

Tip: If you’re shooting video that will later will be used as background footage, try shooting slightly out of focus to give a more realistic depth of field look. Remember, if your foreground subject is in focus, the background theoretically cannot also be in focus.

And also watch your shadows. If the sunshine on your outdoor background footage casts a shadow to the right, it sure would look funny if your foreground key subject is casting a shadow to the left.

And once again, a Chroma key lighting reminder: It’s more important to fully illuminate your blue backdrop than it is to illuminate your key subject standing in front of it. Generally, two quartz halogen lights mounted high on both sides of the backdrop placed about three feet out from the backdrop do an excellent job of preventing any shadows from being cast by your key subject onto the backdrop. If you haven’t noticed already, shadows can literally ruin any Chroma key effect.

Now go have some fun, play with the Chroma Key feature on your digital mixer.