Colour TV: This is how it will look when it comes 

10 July 2023 tbs.pm/77693

 

You won’t have to buy yourself a new set

 

Cover of Illustrated magazine

From ‘Illustrated’ for 21 March 1953

IF anyone tells you that the Coronation is to be televised in colour, don’t believe it (writes Douglas Walters). Far too many rumours of this kind are circulating; all are untrue. Ordinary black-and-white TV itself needs considerable improvement before the B.B.C. can afford expensive colour research on any large scale.

But do not attribute this to any native British slowness just because you have heard somewhere that TV is only a pipe dream in this country and a flourishing reality in America. That is equally false. There is no regular colour TV service in the U.S.

What is true is that, quietly and without fuss, at least three British radio firms, Electrical and Musical Industries, Ltd., Pye Radio of Cambridge, and the Marconi Company, as well as the B.B.C. Research Department at Kingswood Warren, Surrey, are experimenting in this direction. I have seen excellent colour TV demonstrations on three of these equipments. But it is one thing to get results in a laboratory, and quite another to duplicate these results in homes all over the country.

There is nothing new about colour television. John Logie Baird demonstrated it in a crude form in 1928 — barely two years after his historic demonstration in Soho of the first TV pictures.

Beautiful Pastel Shades

A man holds a black disc up to the light; there are 6 cut-out sections in chevron-shapes, green, red, blue, green, red, blue

The disc is made up of colour filters through which pictures are taken in rapid succession by a standard TV camera. Receivers are equipped with identical discs

One of the most noticeable features of the colour system evolved by E.M.I. at their Hayes laboratories is the soft pastel shades of the picture. Reds and greens are not over-emphasized or too vivid as in some earlier colour photographs, and the picture is most restful.

I saw an Illustrated cover reproduced with remarkable clarity, and flowers and dresses all “came through” in natural colour. But the most impressive moment came when a second camera outdoors slowly “panned” across the countryside. Green fields, red brick buildings, and in the distance, the haze of London, were beautifully reproduced on the twelve-inch screen. This was the first time I had seen an outdoor scene televised in colour, and I then realized how much we are missing with plain black-and-white pictures.

For this demonstration a standard TV camera as employed in B.B.C. studios was used. Revolving in front of the lens was a disc containing transparent colour filters in the order red, green and blue. The usual B.B.C. black-and-white TV service operates with fifty picture frames a second. Modern colour apparatus operates at 150 picture frames, so that by speeding up the process three times it is possible to transmit, in succession, TV pictures through red, green and blue filters.

At the receiving end, an identical spinning colour disc synchronized in speed with the transmitter disc produces a rapid succession of red, green and blue pictures. Now, as the eye cannot discern as separate movements anything faster than about twelve and a half a second, the three colour pictures are effectively merged into one, combinations of red, green and blue giving all other colour shades as well as a good white.

Other considerations which make it impossible for colour TV to appear overnight are cost, which certainly will be considerably higher than for black and white equipment, and sorting out transmitting frequencies or wavelengths. The TV transmitter at Alexandra Palace, London, occupies in the ether a block of frequencies which would accommodate three hundred separate sound programmes. A colour TV transmitter needs three times this already great ether space, or “bandwidth,” as it is called.

Blocks of wavelengths or frequencies for various services are allocated by international agreement and there are two practical bands set aside for TV — the 41-68 megacycles band at present fully occupied by the five main B.B.C. TV transmitters, and the 174-216 megacycles band, which is used in America. The higher frequency band, corresponding to wavelengths of the order of one-and-a-half metres, would have to be used for colour TV, but on this band there is room for only three or four “colour” stations.

 

 

Costlier Colour Gear

But colour TV on these shorter wavelengths would have a shorter range than the others, calling for more transmitting and relay gear, more expensive receivers using a greater number of valves, more accurately adjusted receivers.

Obviously, if colour TV is to be transmitted on the 174-216 megacycles band, existing black and white TV sets will have to be fitted with converter units to receive these frequencies.

Too much haste led to chaos in America. Two rival broadcasting networks, C.B.S. and N.B.C., have been competing for the Colour TV Stakes. C.B.S., with its mechanical disc system, won the first round, and was licensed to inaugurate a commercial service. N.B.C., whose parent company, the Radio Corporation of America, is developing a better all-electronic system, tried in vain for an injunction to restrain its rival from starting the world’s first colour TV broadcasts.

Four months later, in October, 1951, the Defence Mobilization Director ordered the service to stop. Ostensibly this was because the defence programme required the components and valves, but very few colour sets were sold, and the hasty introduction of a system which might soon have become obsolete was obviously a “flop.”

When a proved, reliable system of colour TV, receivable by existing sets in black and white, or in colour following a simple conversion, is finally adopted by the B.B.C., it will mean a revolutionary change for artists, make-up and wardrobe departments and producers, as well as viewers. Such a system, say experts, should be in operation within four or five years.

Above all, the viewer for the first time will see things just as they would appear if he were standing next to the camera. And, short of three-dimensional television in full colour, that is about as near to reality as we shall ever get.

 

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