The pictures and text on this page are from posts made by Chris Long on Facebook
BAIRD COMPANY LINK WITH PHILO FARNSWORTH, 1935. Contrary to popular belief, Baird was NOT "committed 100%" to mechanical scanning. By 1933, most Baird receivers for high definition reception had reverted to CRT display (though mechanical devices were still used for receiving the BBC's concurrent 30-line service). By 1935, Baird's company was groping towards electronic camera design, but the attempt to link with Farnsworth and his "image dissector" technology did not, by all accounts, produce pictures that were as clear, as geometrically true, or as reliable as scanning disc/interfilm/flying spot technology - even within the same 240-line scanning standard. The Farnsworth cameras were rarely used in the 240-line broadcasts in the first three months of tests from the Alexandra Palace. An account of the tests with Farnsworth gear at Bairds' Crystal Palace studios refer to the pictures as "being shaped like a banana", which was probably a reference to severe barrel or pincushion geometric distortion. The image dissector, though an ingenious development, also had no charge storage ability, making it far less sensitive than the EMI's Emitron or Zworykin's iconoscope. Another problem was the obstruction of the optical path behind the lens by the image dissector's 'target structure', which must have put some shading on the image, even with the camera lens set at maximum aperture. These photographs confirm that an enormous amount of lighting was required to get a noise-free picture from the image dissector camera. Even when used as a telecine device (see photo), the geometric distortions were such that scanning discs seemed to provide superior pictures. With mechanical-optical techniques, the scanning spot could be very well defined, as well as ideally shaped, and the picture geometry was near perfect. The imperfect state of electron optics and Farnsworth's scanning system - at least in 1935 - could not produce competitive results, even at a 240-line resolution.
Farnsworth image dissector camera used by Baird 's company 1935-36
Baird's "Studio 3" at the Crystal Palace. Farnsworth image dissector cameras.
BAIRD'S CRYSTAL PALACE STUDIOS, 1935 - lighting arrangement for the Farnsworth image dissector camera. Note that AT LEAST 11 kW of lighting, including arcs, were to be used for these cameras. The people being televised would have been damn near roasted. It's a good thing that London has a cool climate!
The two lighting arrangements for the Farnsworth cameras
The Farnsworth cameras in action, studio 2 of Baird's Crystal Palace studios. Note the enormous amount of lighting on the subject, the white "back-screen" and the unusual camera dolly.
Interior construction of the Farnsworth image dissector, tried by Baird's during 1935-36.
Farnsworth image dissector tube (on right) used as part of an experimental telecine at Baird's Crystal Palace TV studios, 1935-36. Background, top left (and slightly out of focus), you can just see Baird's mechanical scanning disc telecine, which apparently gave superior pictorial results.
The position of the two studios in which the Farnsworth image dissector camera was tried at Baird's Crystal Palace studios, 1935-36 (red rectangles)
A musical scene being televised by Farnsworth image dissector camera in studio 3 of Baird's Crystal Palace studio complex, 1935.
