NTSC: Yesterday, Today, Forever?

Understanding the concepts that drive the technologies we use always provides a powerful advantage for both professional and hobbyist videographers. Part of this understanding involves exploring the standards around which these technologies developed. In 1953, the National Television Systems Committee (NTSC) developed the United States standard for broadcast television, which remains the standard used today throughout North America.

In Living Color
The NTSC standard moved us from the gray lands of black and white images into the modern world of color television. With this transition arose certain obstacles associated with a video signal that not only had to include and transmit color information, but which also had to be backwards compatible with existing black and white televisions. To achieve this result, a color video signal begins just like a black and white signal. An eight-cycle sine wave that generates the color burst is then added to the signal.

Modern color televisions use red, green and blue (RGB) colors to create the full rainbow we see. The most common and economical types of televisions on the market are cathode ray tube (CRT) televisions that create color images by shooting beams of electrons onto colored phosphors, which are simply compounds that emit light when they're struck by electrons. A layer of phosphor dots coat the (inside) face of a television's picture tube and, as an electron beam traces lines across the picture screen, the phosphors glow and create the images you see as motion picture.

An NTSC television display reveals about two million different colors. By comparison, current CRT-based computer monitors support the Video Graphics Array (VGA) standard, which can show 16.8 million colors, also called true color.