The development team, under Mike Spooner, was led by Geoff Pryke, supervisory engineer, planning, and consisted of Bob Warren, Dave Johnson, George Jackson, Eric Ruckle, Jack Nichols, Peter Koller, Jim Beasley and Dave Skeate.

Great assistance was given by Jim Crossley and Jim Runkel throughout, and also involved of course, was mike metcalfe, engineer-in-charge, E-cam ops., the author of this article.

The concept of E-cam was born from a desire to produce high quality film programmes by television methods. If this long standing dream of programme producers could be realised, it would not only reduce production costs, but would overcome the serious technical problems associated with the international exchange of programmes for television.

The varying line standards of the television systems used throughout the world severely inhibit the free exchange of programmes, and a conversion process is necessary before material recorded in one country can be played back in a country with different line standards.

Originally the conversion process was an optical transfer, and in essence, consisted of a television camera on one standard, viewing programme material displayed on a monitor of a different standard.

Later developments have removed the optical transfer and are purely electronic with consequent gains in picture quality. The system works well for black-and-white material and can be used for live or previously recorded programmes.

The future interchange of colour programmes, however, presents an acute problem. Not only must consideration be given to the line standards of the countries concerned, but also the system of colour television employed, there being several in current use throughout the world and variants of each.

Programmes on film however, do not suffer from these technical limitations as the telecine machine used to transmit a film is already working on the required system and so the process becomes automatic.

This applies to both black-and-white and colour films – if the telecine is colour equipped of course – and removes completely the problem of conversion and colour system compatibility. Since all television stations possess telecine equipment, film has become the universal currency of programme exchange. However, film making by traditional methods can be long and expensive compared with television, and various ways have been sought to combine the best of both techniques.

The idea of coupling a television camera to a film camera in order to monitor the scene remotely and to facilitate the control of several cameras simultaneously is not new. A photo-recording system was devised in 1955 by Dumont in New York in collaboration with Arnold & Richter of Munich, and although it had limited success, it nevertheless showed the value of the concept. Since that time, several systems, using both 16 and 35 mm. film in various configurations have been developed, each having its own particular advantage. In the latest development of Electronicam the film camera used, a well tried Arriflex 35 mm., has been developed by Arnold & Richter from the original prototype system of 1955. The television channel using a Plumbicon picture tube and embodying the latest circuitry, was produced by Fernseh in collaboration with our own engineers, to a first-class broadcasting specification.

Briefly, the system works as follows. Light from the studio scene is focused by a zoom lens on to the film in the camera gate. A specially designed reflex shutter in front of the film gate has two reflecting segments. These mirrored sections allow a proportion of the available light to be reflected through a suitable system of correcting lenses into the Plumbicon camera attached to the side of the film camera.

The two mirrored sections of the shutter are of equal area, one operating during film pull-down and the other during film exposure. The shutter revolves at a constant speed of 25 frames per second, giving the two equal exposures per revolution necessary, one for each field of the television picture. The mirror segments are so arranged that the film receives full exposure at ¹⁄₅₀ sec.

The television picture, therefore, is an exact replica of the scene viewed through the film camera lens and is available to a monitor viewfinder mounted at the back of the camera. The cameraman uses this viewfinder in exactly the same way as in a television camera and has normal control of zoom, focus and framing etc. The television picture is also available to monitors in the various control rooms.

The method of operation follows closely that of a standard television studio production. Pictures from all cameras are permanently available to the director whether the film is running or not. Rehearsal takes place in the usual manner and film is only exposed for the actual transmission/take. During rehearsal when film is not being exposed, an estimate of the amount of film to be used during the subsequent take is indicated by footage counters, one for each camera, displayed on the control desk. Careful pre-planning ensures that the sequences are arranged for the most economical use of each camera’s 1,000 ft. magazine of film (approximately 10 minutes running time) and that no camera runs out of film during the take. The actual transmission/take is accomplished by pressing the appropriate button on the simple vision mixer panel which starts the film camera and switches its television picture to ‘transmission’. Cutting from one camera to another is achieved by pressing the appropriate buttons, and after a delay of approximately ⅓ second, to enable the camera motor to attain speed, the vision is automatically switched and the film exposed.

For fast cutting sequences an extra button is provided enabling the selected cameras to stay running while cutting between them, thus obviating the running-up delay. This method, of course, is wasteful of film and should only be used for short periods. As it is not possible to fade or mix between the film cameras, the vision mixer is a simple ‘cut only’ device. Opticals and other effects are added where required in the film laboratories.

Programme sound is recorded in the normal way on sprocketed magnetic tape running in synchronism with the film cameras. To facilitate the later assembly of the processed film, a cue tone, having a different frequency for each camera, is recorded on the magnetic sound tape on another track alongside the programme sound. These tones are selected automatically by the vision mixer’s cut buttons. During the assembly of the processed film, the cue tones are played back on a synchroniser to identify the camera and to serve as a guide for the assembly of the film.

To allow the lighting director to maintain consistent film exposure, the lens iris of each camera can be remotely operated from the lighting control console. Comprehensive picture and waveform monitoring facilities are available to the exposure controller and the lighting director to enable the close exposure tolerances required for successful colour filming to be maintained.

By close control of the electronics (which require a high degree of stability) the television camera can be used as an exposure meter and the high definition pictures from it give a continuous indication of what the film is recording. The system is equally capable of filming in colour or black-and-white, and it is in its colour role that its greatest virtue will become apparent. At a time when the complexity of interchanging colour programmes recorded electronically is becoming apparent, the E-cam system can be a vital link in the chain of international programme exchange.

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“Television is the art of instantaneously producing at a distance a transient visible image of an actual or recorded scene by means of an electrical system of telecommunication.”

The wording of the British Standards Institution’s definition of our work, gives a somewhat unimaginative description of an art form that has, perhaps, a most complex method of construction to produce small black- and-white shadows, yet also has a high degree of human attraction.

The first process in any television system the creation of an optical image of the scene to be transmitted. This optical image is formed in the case of cameras by the camera lens, and is focused by it on to the face of the pick-up tube inside the camera. It is then the function of the pick-up tube to convert the light image into an electrical current which varies in magnitude, in proportion to the amount of light reaching the tube from each part of the scene at any given time.

The exchange of light for an electrical current is the principle upon which a photographic exposure meter works. The tiny light-sensitive cell in an exposure-meter gives a small electrical current in direct proportion to the average light value of the subject which it is seeing and registers this visually on a scale.

This device, invaluable for photographers, is useless for television because it cannot convey information about the detailed structure of the scene. In the past many methods were tried, using the light-sensitive or ‘photo-cell’ as it is called, to break up the picture into small parts and to allow the photo-cell to look at one part at a time in strict sequence and to register a separate value of current for each. This is similar to the way in which the eye ‘scans’ a printed page, gleaning different information word by word and line by line.

Baird scanned his scene by means of an opaque rotating disc containing a series of holes in the form of a spiral placed in front of his photo-cell. The spiral was arranged so that, as the disc revolved, each hole in turn swept across the picture, allowing the photo-cell to see a small, continuously varying part of the scene. When the last hole had completed its scan across the bottom of the picture, the first appeared and started the operation at the top again. The current from the photo-cell was proportional at any instant to the amount of light reflected through the hole from the scene.

Another method reflected light from the scene by means of a revolving drum containing mirrors set on the outside in a staggered formation. When the drum revolved at high speed, each mirror reflected into the photo-cell light from a slightly different part of the scene each time.

These mechanical methods, however, suffered from extreme clumsiness of operation and poor definition because of their inability to scan the scene in small enough elements. A ‘major break-through’, as the popular press would now call it, was the innovation of a vacuum tube with electrical scanning.

This tube, rather like a large valve, was developed in this country in the early 1930’s and brought the first high- definition television system in the world into operation in 1936. The tube was called an Emitron or Iconoscope and was cumbersome, insensitive and, by today’s standards, somewhat crude in operation, but was in fact the parent of most present-day camera tubes.

In appearance it consisted of a cylindrical glass tube about 14 inches in diameter, one end of which blossomed into a bulb about 7 inches in diameter. The bulb had a flat window on one side and inside, parallel to the window, was mounted a ‘target’ upon which the optical image of the scene formed by the lens was focused. The tube joined the bulb at a slight angle and contained a device like a gun, which in effect fired a tiny stream of electrically-charged particles at the target.

This fine beam of charged particles called ‘electrons’, was made to sweep over the target in straight lines one below. the other, starting from top left of the picture through to bottom right and back to top left again. This sweeping or scanning could be achieved electrically at enormous speed and in fine detail because electrons are so small that they are almost weightless. At first sight this may appear to be unconnected with our original problem, which was the inability of the photo-cell to distinguish between the brightness details of a picture. In order to see in what way this can be useful, we must consider more closely the function of the target.

The target (so called because the optical image lands there as well as the electron beam) is made up of a sheet of mica covered on the front with a mosaic of many thousands of tiny photo-cells, each one insulated from each other and able to work independently. The mica sheet is then backed by a metal plate.

The situation is now that the optical image projected on to the target by the lens is not falling on one photo-cell but on many thousands so that each one is receiving an amount of light in proportion to the brightness of that particular element of the original scene. Part of our problem has, therefore, been solved, as the scene can now be divided into many small elements and each photo-cell can give a separate value of current.

As always, of course, there is a snag. What was an advantage at first sight now becomes a problem, because as soon as light falls on to the mosaic all the photo-cells merrily start to produce a current which they store rather like a battery. This current is not all required at once, and this is where the beam of electrons comes into its own.

As it scans the mosaic, it acts like a switch and touches each photo-cell in turn, causing them to discharge their stored current to the metal plate at the back of the target.

This current can be collected and forms the signal output of the tube representing at any given instant the discharged current of one photo-cell and, therefore, the electrical equivalent of one picture element. As this is changing extremely quickly there is a continuous output from the tube which is called the ‘video signal’. This signal is amplified and processed in many ways to become the transmitted picture, which when re-created by the receiver builds ‘a visual image of an actual or recorded scene…’ as in the definition.

This then was the first attempt at high definition tele- vision and many improvements followed fairly rapidly. Perhaps the most significant was the separation, in the pick-up tube, of the two functions performed by the target of electrical image creation and scanning. This was achieved by placing in front of the target a semi-transparent sheet having photo-electric properties which gave an electrical magnification and greater sensitivity. This type of tube was called an image iconoscope. The construction of the target was also modified to have a greater electrical storage, i.e. a larger battery, which was then scanned in much the same way as before.

These tubes were in use for a number of years and were in fact still used after the war.

Still further increases in sensitivity have been made and more efficient and complex tubes are now used by most television broadcasting organisations. The ‘image orthicon’ which is used for television broadcasting cameras, is perhaps the most versatile and widely used tube today. It has such sensitivity that in certain cases it will give a reasonable picture by moonlight. Its method of signal production does, however, differ from the image iconoscope but the same basic principles apply to both.

Another new tube, the ‘Vidicon’, is used extensively in telecine machines and industrial cameras and indeed some of the most significant developments of recent years have been in the field of vidicon tubes which, because of their small physical size and relative cheapness (£25 as against £450 approximately for an image orthicon), have been much favoured and will doubtless become increasingly useful in a wider field when certain fundamental snags are overcome.

Television cameras have many uses in fields other than broadcasting and one of the most significant has been their introduction into the field of medicine. Here, their use is obvious as a means of allowing many hundreds of students and nurses to view on closed circuit a major surgical operation, often in colour, which only a few at a time could normally watch in an operating theatre.

Additionally, because of their sensitivity under certain modified conditions of working, television cameras can be used to intensify an X-ray image in order to keep the ‘dosage’ of X-rays to a minimum for the patient while still providing a satisfactory picture under deep penetration conditions.

The use of television cameras in space-satellites is only just beginning and recent developments have been rapid indeed, as has been similar progress for the armed forces. So, from the humble photo-electric cell and Baird’s scanning disc of the 1920’s, has grown a world-wide industry employing many hundreds of thousands of people of varying skills which, I think it is fair to say, can give pleasure, entertainment, instruction and a means of research on a scale quite undreamed of even 30 years ago.

Of the future we can only make an intelligent estimate based on the rate of growth to date and the present state of the art and science.
That international exchanges of vision and sound will take place on a day-to-day basis and that trans-Continental networks will be available for world events is obvious from present indications.

That many future transmissions will be in colour and possibly stereoscopic as well would be a natural extension to the reality of today’s programming.

That more and more use of closed circuit viewing will be likely perhaps for specific programmes on a wired ‘pay as you view’ service, and eventually as an added facility to the telephone service.

Whether television could be made cheap enough for domestic use ‘See if junior is asleep in the nursery’ type of thing is debatable at present. Certainly a flat picture-frame type of viewing tube is possible and indeed in development at present.

That we shall explore, remotely at first, the outer edges of space and the depths of the oceans is again highly likely. In all these projects, however, the television camera tube has played and will continue to play a vital part in what is, perhaps, the most exciting medium of communications of our age.

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‘Three Roads to Rome’ was the composite title of three separate plays, starring Deborah Kerr and with a glittering cast including Celia Johnson, Isobel Dean, Anthony Newlands, Jeremy Brett and Alan Cuthbertson.

Associated-Rediffusion provided the full technical facilities of Studio 5, and the whole of its production resources for the 525-line video tape recording. It was soon obvious that the entire 14,000 square feet of floor would be required to house the biggest sets since ‘An Arabian Night’, including a full-sized ‘practical’ carousel in an Italian market square.

Ronald Marriott, aided and abetted by his P.A., Helen the Best, became thinner but wiser as director, while the Americans sent a colourful quartet of producers to assist him. In order of meeting they were:

enter (at ceiling height) briskly: John B. Green (Executive Network Producer) quickly known as ‘Big John’. This could be because he was at least nine feet high and came from Texas. (Why doces he never stand still? Is the weight too much for the floor for more than a minute? ‘Hush dear, he’s thinking!’)

enter (legato con moto) ‘Beau’ Goldman (bow-tied associate producer and musical adviser): ‘Say, Beau, have you met Steve Race? He will write your music.’

exit Both (Control Room left) together with scripts, stop watches, blank music sheets, frowns and a brace of P.A.s.

enter (quietly, politely, inquiringly) Arthur Penn, legendary film, Broadway and television producer and other half of COE PENN production partnership. He is small, tweedy, bespectacled, but with an air of intent. ‘You say we can have eight cameras, all on two-shot? – That’s just fine!’

exit — with Ronald Marriott to floor, in a hurry.

enter – Bold Fred (Coe), fresh from Paris and preceded by his ‘you-name it — he’s done it and at the moment he’s television adviser to the President and they don’t come any bigger than KING SIZE’ – reputation. ‘Good morning’ (formal introductions) and, quick exit to his private viewing room (with telephone to gallery) calling over his shoulder: ‘Arthur, I want to talk to you about the lighting, and another thing, that scene where we are’ … A pause, quiet descends, the gallery settles and from the studio the pleasantly Welsh voice of floor manager Eric Cooper calls for quiet. Fred Pusey’s delightful Forum and Rome hotel balcony set appears on camera 1.

The cultured American voices (how beautifully Deborah and Celia have slipped into character) engage in the opening dialogue of ‘Roman Fever’ – the first play.

It is Monday morning. Vic Gardiner’s five cameras cluster above, below and all around the hotel balcony balustrade, sections of which are being continuously moved, just in case one of the five cameras can get a better two-shot, or maybe a small trench for the crane would give … a … better …

Before we had finished in the studio some four days later we had all learned a great deal about American production techniques. Quickly we found how to live with and interpret their methods and techniques to their satisfaction, while at the same time bringing our own individualism to the finished product.

Did I say finished?

The V.T.R. Room at Wembley looked like a first feature cutting room with a world premiere brought forward a month. From this do-it-yourself drama kit, Jim Runkle’s recording team, Harry Baker in charge of V.T.R. and Theo Duka in charge of tele-recording sound, worked like beavers to cut together a rough working copy from the dozens of ‘takes’ and bits of tape in order that the producers could have some idea of the production as a whole on the following day. (Perhaps even a timing.)

This was done on Friday and Saturday while Steve Race, with copious notes, a buzzing head and the prospect of a heavy week-end was charged to write the incidental music by Monday morning’s 9 o’clock band call. The American technique for major productions is to record the music and any effects required, post-sync sound, as in feature films. This was an innovation in live television production as far as we were concerned and considerable knitting of facilities was required to achieve it. It was, as far as I know, the first time that the techniques of live television, film sound and video tape had all been combined in this way.

On Monday morning, we assembled in Studio 5 to view the final cut working copy and to record the musical backgrounds required at intervals throughout the 90-minute production. Tony Bristow kept a firm hand and his urbane disposition visible throughout and the session was successfully concluded just as the last over-coated musician left the studio.

With, it seemed, an ever-increasing kit of parts, we ascended on the Tuesday morning to the dubbing theatre at Television House where George Willows and his crew bade us welcome, while Freddy Slade sharpened his chinagraph and his wits for the master mix. Sound tracks wild and sound tracks sync were combined to sound track master and while a fascinating series of numbers flashed by on the projection screen, the V.T.R. picture from Wembley appeared, as if by magic on cue from the dubbing mixer. (Sheer fantasy this!) Tracks were moved, cut, laid, wiped, stretched, blooped, padded, blanked and generally administered by ace cutter, John Butler, who was able to remove ‘dead air’ not by a fan, but by moving music tracks to cover dialogue pauses.

The prospect of replacing the theatre carpet was causing George Willows some alarm (Why can’t John B. Green sit down?). Ronald Marriott was down to his last set of finger nails and now had pins and needles in both legs. Faces various, looked in, paled, and left rapidly; but by Wednesday afternoon, it looked as if we had won. Thursday saw the happy wedding of track master sound, to track V.T.R. vision, while Friday morning saw the first-off replay of the entire production to most of the principals and cast.

The quality of all aspects of the production were the subject of very considerable praise from the Americans and the occasion for not inconsiderable sighs of relief from us. The impeccable lighting of Bob Gray gave Don Furness, in charge of racks, the opportunity to produce some of Studio 5’s finest pictures. During the production it was fascinating to see how the expert make-up, under the direction of Mary McDonough, coped with the changes in age and character of Deborah Kerr, who although rarely off the set for more than a few minutes at a time gave a shining example of patience and sweetness which charmed everybody. Her casual asides during the inevitable moments of tension reduced the floor to near hysteria on several occasions.

Much of the great success of this operation was due to the enormous co-operation given by everybody and the mustering of Associated-Rediffusion’s production facilities under the supervision of programme coordinator, Lloyd Williams. A complicated operation? Expensive? Time-consuming? Yes, possibly all three. But for first-class quality and guaranteed results on a national network where these factors count above all, come to Associated-Rediffusion, as ABC did.

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