Oz color difference

[cbenham]

Originally Posted by colorfixer

From Wikipedia's article on Oz:

"It was also very common (and even an FCC requirement for early color broadcasters) for TV stations to turn off the color portion of their transmission when broadcasting a black and white show or movie. This was because unusual colors or "color noise" could be seen during the showing of black-and-white programming under some conditions.

The FCC finally ended the practice of turning off burst for B&W programs in the early 1980s because the broadcast studio TV gear being manufactured then required the incoming signal to contain "sync coherent subcarrier". This means that the color subcarrier and the sync signal had to be locked together and mathematically related or the equipment would not pass the video signal. To broadcast a B&W film, I devised a way to turn off the I and Q video in the filmchain camera while still leaving the color burst on in the monochrome video output. This way the color shading problems in the filmchain camera were not visible to the viewers with color sets.
Cliff