Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Field-sequential color system
A field-sequential color system (FSC) is a color television system in which the primary color information is transmitted in successive images and which relies on the human vision system to fuse the successive images into a color picture. One field-sequential system was developed in 1940 by Peter Goldmark for CBS, which was its sole user in commercial broadcasting. The Federal Communications Commission adopted it on October 11, 1950, as the standard for color television in the United States. Its regular broadcast debut was on June 25, 1951. However, a few months later, CBS ended color broadcasting on October 20, 1951. In March 1953, CBS withdrew its color system as a standard, creating an opening for all-electronic color systems from other manufacturers.
In the late 1960s, NASA revived the Goldmark-CBS system to broadcast color video from Project Apollo Command Modules, using a camera developed by Westinghouse Electric Corporation. The Westinghouse color camera was adapted to eventually broadcast from the lunar surface itself. Starting with Apollo 10, in May 1969, sequential color TV cameras flew on all NASA human spaceflight missions until the late 1980s, when CCD-based cameras replaced them. After the turn of the 21st century, consumer Digital Light Processing (DLP) projectors use a single chip and produce color by the sequential color process, using a color wheel for both front and rear projectors.
According to television historian Albert Abramson, A. A. Polumordvinov invented the first field-sequential color system. Polumordvinov applied for his Russian patent 10738 in 1899. This system scanned images with two rotating cylinders. A later German patent by A. Frankenstein and Werner von Jaworski described another field-sequential system. Like the CBS System, this patent included a color wheel. Frankenstein and Jaworski applied for their patent 172376 in 1904.
John Logie Baird demonstrated a version of field-sequential color television on July 3, 1928, using a mechanical television system before his use of cathode ray tubes, and producing a vertical color image about 4 inches (10 cm) high. It was described in the journal Nature:
Baird demonstrated a modified two-color version in February 1938, using a red and blue-green filter arrangement in the transmitter; on July 27, 1939 he further demonstrated that colour scanning system in combination with a cathode ray tube with filter wheel as the receiver. By December 1940 he had publicly demonstrating a 600 line version of the system.
The CBS field-sequential system was an example of a mechanical television system because it relied in part on a disc of color filters rotating at 1440 rpm inside the camera and the receiver, capturing and displaying red, green, and blue television images in sequence. The field rate was increased from 60 to 144 fields per second to overcome the flicker from the separate color images, resulting in 24 complete color frames per second (each of the three colors was scanned twice, double interlacing being standard for all electronic television: 2 scans × 3 colors × 24 frames per second = 144 fields per second), instead of the standard 30 frames/60 fields per second of monochrome. If the 144-field color signal were transmitted with the same detail as a 60-field monochrome signal, 2.4 times the bandwidth would be required. Therefore, to keep the signal within the standard 6-MHz bandwidth of a channel, the image's vertical resolution was reduced from 525 lines to 405. The vertical resolution was 77% of monochrome, and the horizontal resolution was 54% of monochrome.
Because of these variances in resolution and frame rate from the NTSC standards for television broadcasting, field-sequential color broadcasts could not be seen on existing black and white receivers without an adapter (to see them in monochrome), or adapter-converter (to see them in color).
The CBS Sequential Color TV system was first demonstrated to the press on September 4, 1940. A color 16mm film was telecined to a color TV set and shown to the gathered press in Peter Goldmark's New York CBS lab. Live color from television cameras in a studio was first demonstrated to the press in 1941. The system was first shown to the general public on January 12, 1950.
Hub AI
Field-sequential color system AI simulator
(@Field-sequential color system_simulator)
Field-sequential color system
A field-sequential color system (FSC) is a color television system in which the primary color information is transmitted in successive images and which relies on the human vision system to fuse the successive images into a color picture. One field-sequential system was developed in 1940 by Peter Goldmark for CBS, which was its sole user in commercial broadcasting. The Federal Communications Commission adopted it on October 11, 1950, as the standard for color television in the United States. Its regular broadcast debut was on June 25, 1951. However, a few months later, CBS ended color broadcasting on October 20, 1951. In March 1953, CBS withdrew its color system as a standard, creating an opening for all-electronic color systems from other manufacturers.
In the late 1960s, NASA revived the Goldmark-CBS system to broadcast color video from Project Apollo Command Modules, using a camera developed by Westinghouse Electric Corporation. The Westinghouse color camera was adapted to eventually broadcast from the lunar surface itself. Starting with Apollo 10, in May 1969, sequential color TV cameras flew on all NASA human spaceflight missions until the late 1980s, when CCD-based cameras replaced them. After the turn of the 21st century, consumer Digital Light Processing (DLP) projectors use a single chip and produce color by the sequential color process, using a color wheel for both front and rear projectors.
According to television historian Albert Abramson, A. A. Polumordvinov invented the first field-sequential color system. Polumordvinov applied for his Russian patent 10738 in 1899. This system scanned images with two rotating cylinders. A later German patent by A. Frankenstein and Werner von Jaworski described another field-sequential system. Like the CBS System, this patent included a color wheel. Frankenstein and Jaworski applied for their patent 172376 in 1904.
John Logie Baird demonstrated a version of field-sequential color television on July 3, 1928, using a mechanical television system before his use of cathode ray tubes, and producing a vertical color image about 4 inches (10 cm) high. It was described in the journal Nature:
Baird demonstrated a modified two-color version in February 1938, using a red and blue-green filter arrangement in the transmitter; on July 27, 1939 he further demonstrated that colour scanning system in combination with a cathode ray tube with filter wheel as the receiver. By December 1940 he had publicly demonstrating a 600 line version of the system.
The CBS field-sequential system was an example of a mechanical television system because it relied in part on a disc of color filters rotating at 1440 rpm inside the camera and the receiver, capturing and displaying red, green, and blue television images in sequence. The field rate was increased from 60 to 144 fields per second to overcome the flicker from the separate color images, resulting in 24 complete color frames per second (each of the three colors was scanned twice, double interlacing being standard for all electronic television: 2 scans × 3 colors × 24 frames per second = 144 fields per second), instead of the standard 30 frames/60 fields per second of monochrome. If the 144-field color signal were transmitted with the same detail as a 60-field monochrome signal, 2.4 times the bandwidth would be required. Therefore, to keep the signal within the standard 6-MHz bandwidth of a channel, the image's vertical resolution was reduced from 525 lines to 405. The vertical resolution was 77% of monochrome, and the horizontal resolution was 54% of monochrome.
Because of these variances in resolution and frame rate from the NTSC standards for television broadcasting, field-sequential color broadcasts could not be seen on existing black and white receivers without an adapter (to see them in monochrome), or adapter-converter (to see them in color).
The CBS Sequential Color TV system was first demonstrated to the press on September 4, 1940. A color 16mm film was telecined to a color TV set and shown to the gathered press in Peter Goldmark's New York CBS lab. Live color from television cameras in a studio was first demonstrated to the press in 1941. The system was first shown to the general public on January 12, 1950.