David Tamés |
August 28th, 2007 03:32 PM |
It does in fact have to do with the 7.5 IRE set-up (pedestal). The "standard" for digital video is blacks are at 0 IRE. But the "standard" for analog video is black at 7.5 IRE. So by default, according to the "standard" DVD players ADD 7.5 set-up to the video on the analog outputs. When you edit digital video, you need to make sure your blacks are all at 0, not 7.5, so when the DVD player adds the "standard" 7.5 set-up, your blacks only get slightly milky, rather than really milky. Some DVD players will allow you to change this setting, most do not. This is all a hold-over from ancient times when analog TV sets had trouble telling the difference between 0 and negative synchronization signals so the engineers decided to make black 7.5 rather than 0 for broadcast. How nice. There goes solid blacks. Not a problem in the era of CRT screens (grey surface to start with), but on LCD monitors, plasma displays, and projectors, the 7.5 is visible as non-black.
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