Color Temperature

White light is a combination of all the colors of the spectrum, as you've seen when playing with a prism or looking at a rainbow. As such, it's not going to always be white while you're filming a myriad of factors can make images appear with a colored cast, leading to video footage that looks a little too green, or blue, or any number of shifts.

Your camcorder automatically adjusts to compensate for this color temperature of the light by setting the white balance. Essentially, this is the color that the camera sees as white, causing the camera to adjust the display of the rest of the colors based on this setting. You probably have a few basic controls for changing the setting, such as Auto, Indoor, or Outdoor presets (Figure 4.3).

Figure 4.3. Many camcorders feature the capability to adjust the color temperature it displays. It's difficult to tell from these black-and-white images, but the top picture has a blue cast, while the bottom picture appears a warmer red. (You can see these frames in color at www.necoffee.com/imovievqs/.)

graphics/04fig03.gif

You may also be able to manually specify the white point by selecting Manual and filming a sheet of white paper in the environment where you'll be shooting; the camera will use the values it captured as the basis for the other colors.



iMovie 3 for MAC OS X. Visual QuickStart Guide
iMovie 3 for Mac OS X (Visual QuickStart Guide)
ISBN: 0321193970
EAN: 2147483647
Year: 2003
Pages: 125
Authors: Jeff Carlson

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