1000\/1001

HD

When the NTSC color television system was being developed, the designers wanted to make it compatible with all of the old black and white systems that were already in people’s homes. To do this, they had to make some compromises. The thing that has probably caused the most problems for our industry over the years is that the field rate was changed by 1\/1.001 from 60 to 59.94 per second. This was a small enough change that the older TV’s would still receive the new color broadcast and allowed for the new color information to be encoded into the broadcasted signal. This offset gives rise to “niceties” such as drop-frame timecode and audio that also has to run at the right rate. Although having analog origins, it has also been extended into the digital and HD world where 24, 30, and 60 frames\/fields per second becomes 23.98, 29.97, and 59.94 to be compatible with existing NTSC formats and workflows.