Quote:
Originally Posted by freakaftr8
Way cool! Hey That's interesting ir respect to the owners of black and white sets and how they started producing "high definition" like Sarnoff stated. I can imagine that the greyscale gamut just got more broad with the transition to color cameras. Would I be correct to say that there was a change in greyscales between the black and white cameras and color cameras?
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That is correct, because black and white cameras did not have "gamma corrector" circuits, but instead operated the image orthicon "above the knee", that is, with partly linear and partly highlight-compressed transfer characteristics, which were only an approximation for the characteristics of a picture tube. Color cameras, on the other hand, had to be operated in the linear region "below the knee", with a precision gamma corrector circuit in each of the red, green and blue channels. Otherwise. overexposure of one or two of the primary colors would have caused strange colored halos around brightly colored objects. Occasionally, this still happened with bright red clothing. In black and white, these effects were not considered objectionable if not too strong, as they tended to enhance the edge contrast. In old video tapes of live performances, you can sometimes see these dark halos around bright reflections off of jewelry or shiny musical instruments, or even a white shirt.