Once a computer has imported DV footage, it keeps the original source files on the hard disk and creates a series of preview frames to display in the video editing application (Avid, FCP Adobe Premiere...). These preview frames are created by removing much of the video and color information that NTSC televisions require, and simply displaying the frames as they will best appear on your computer monitor
Although these images will appear blocky, fuzzy, or more muted than those seen through the viewfinder of a camcorder, not to worry: These screen images are simply low-resolution stand-ins for the real footage. Once formatted, these preview frames will appear at full screen and full motion, and display much faster than the higher-resolution images of an uncompressed video stream.
Previews make the long and arduous task of editing infinitely more bearable by speeding the response time of video playback. Without these low-res substitutes, even the fastest computers would be unable to display motion pictures in real time. Meanwhile your full-quality original footage remains locked inside the clip by the DV codec until you’re ready to export your final movie in all its glory.Related Posts: DV Shooting Tips