Setting Up The Picture For Chroma Key; Hints For Chroma Key Setup - Videonics MX-1 Instruction Manual

VIDEONICS DIGITAL VIDEO MIXER
Here's how to perform this kind of superhero feat using the MX-1. Begin
with a large piece of brightly colored cloth tacked to a wall. Drape it over the
ground and over a small platform. The cloth covers the platform, the wall,
and the ground. Have your subject balance on the platform.
Adjust your lighting so the background is evenly lit, so the camera sees
only your superhero and the solid color background. Then use the chroma
key feature of the MX-1 to replace the color of the cloth with some aerial
footage of a city and you have turned a high-flying idea into a dramatic
video!

Setting up the Picture for Chroma Key

The key to a successful chroma key is careful setup of the original picture.
Two guidelines are important:
• You want to be sure that all the areas that should be replaced are the right
color and that the color does not appear anywhere else. For example, if the
superhero's shirt were close to the color of the chroma key background,
the skyscrapers of the city would appear through portions of the shirt.
• You want to make sure the background is even and does not contain glare
or shadows that will prevent the chroma key circuitry from recognizing it
as background. For instance, if the subject's shadow darkened the back-
ground enough, the city would not be substituted in the shadows, spoiling
the illusion.

Hints for Chroma Key Setup

• Flying a man over a city is an ambitious chroma key project and it would
be a good idea to start with something simpler. Tabletop miniatures are
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