Telerecording
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Telerecording (known as kinescoping in the USA) is the British name for a process pioneered during the 1940s for the storing of electronically-shot television programmes on film, which was used for the preservation, re-broadcasting and sale of television programmes before the use of commercial broadcast-quality videotape became prevalent for these purposes.
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Technique
Simply put, the telerecording process works by aiming a film camera at a specially adapted large, flat television screen, with the camera shooting at a frame rate in synchronisation with the television frame rate. In the UK, television runs at 25 frames - or more correctly, 50 fields - per second, so the film camera would be run at 25 frames per second rather than the cinematic film standard of 24 frames.
Because television is a field rather than frame-based system, however, not all the information in the picture can be retained on film in the same way as it can on videotape - thus two separate telerecording techniques were developed to deal with this. 'Skip field' recording missed out every other field of video, recording one video field to one film frame. However, this meant that half the information of the picture was lost on such recordings, and the alternative method, 'stored field' came to be preferred - this merged the two fields into one frame of film, giving a much sharper and generally more satisfactory result.
Another technique developed by the BBC for telerecordings was known as 'spot wobble' - this involved the pixels of the television picture being telerecorded being slightly distorted, so that on the telerecording the line structure of the picture would be blurred into one, preventing moiré patterning on re-broadcast of the telerecording.
Even after the advent of commercial broadcast videotape systems in the 1960s, telerecordings continued to be made as they possessed several distinct advantages, particularly for overseas programme sales. Firstly, they were cheaper, easier to transport and more durable than video. Secondly, they could be used in any country regardless of the television broadcasting standard, which was not true of videotape. Thirdly, they could be used to make cheap black and white copies of colour programmes for sale to television stations who were not yet broadcasting in colour.
The telerecording system was actually of a very high quality, easily reproducing the full detail of the television picture. The only slight disadvantage of the system was that it removed the 'fluid' look of interlaced video and 'filmised' the picture, but this would generally not have made a great deal of difference to the viewing audiences.
The system was also almost exclusively used for black and white reproduction. Although some colour telerecordings were made, they were generally in the minority as by the time colour programmes were widely needed for sale video standards conversion was easier and higher quality and the price of videotape had become much lower.
History
The first known surviving example of the telerecording process in Britain is from October 1947, showing the singer Adelaide Hall performing at the RadiOlympia event. The wedding of Princess Elizabeth to Prince Philip also survives, as do various early 1950s productions such as It is Midnight, Dr Schewitzer and the opening two episodes of The Quatermass Experiment, although in varying degrees of quality. A complete 7-hour set of telerecordings of Elizabeth's 1953 coronation also exists.
There is some evidence to suggest that the BBC experimented with filming the output of the television monitor before the television service was placed on hiatus in 1939 - BBC executive Cecil Madden later recalled filming a production of The Scarlet Pimpernel in this way, only for film director Alexander Korda to order the burning of the negative as he owned the film rights to the book, which he felt had been infringed. However, the evidence for this is purely anecdotal, and indeed there is no written record of any BBC Television production of The Scarlet Pimpernel during the 1936-1939 period.
Up until the early 1960s, much of the BBC and British television in general's output was broadcast live, and telerecordings would be used to preserve a programme for repeat showings, which had previously required the entire production being performed live for a second time.
In the 1950s a home telerecording kit was introduced in Britain, allowing enthusiasts to make 16mm film recordings of television programmes. The major drawback, apart from the short duration of a 16mm film magazine, was that a large opaque frame had to be placed in front of the TV set in order to block out any stray reflections - making it impossible to watch the set normally while filming. It is not known if any recordings made using this equipment still exist.
British broadcasters used telerecordings for domestic purposes well into the 1960s, with 35mm being the film gauge usually used as it produced a higher quality result. For overseas sales, 16mm film would be used, as it was cheaper. Although domestic use of telerecording in the UK for repeat broadcasts dropped off sharply after the move to colour in the late 1960s, 16mm black and white film telerecordings were still being offered for sale by British broadcasters well into the 1970s.
Telerecording was still being used internally at the BBC in the 1980s too, to preserve copies for posterity of programmes which were not necessarily of the highest importance, but which nonetheless their producers wanted to be preserved. If there were no videotape machines available on a given day, then a telerecording would be made - there is evidence to suggest that the children's magazine programme Blue Peter was occasionally being telerecorded as late as 1985. After this point, however, cheap domestic videotape formats such as VHS could more easily be used to keep a back-up reference copy of a programme.
Another occasional use of telerecording into the late 1980s was by documentary makers working in 16mm film who wished to include a videotape-sourced excerpt in their work, although such use was again rare.
Legacy
Telerecordings form an important part of British television heritage, not simply because it was a recording standard that lasted for over thirty years, but because it has enabled the preservation of of British television history that would otherwise have been lost. Nearly every single pre-1960s British television programme that survives in the archives is in the form of a telerecording, and the vast majority of existing 1960s output also survives in this form. Videotape was expensive and could be wiped and re-used; film was cheaper, smaller, could not be wiped and has also proven to be much more durable than many early professional broadcast videotapes. It should be noted that only a very small proportion of British television from the black and white era survives at all; perhaps 5% from the 1953-58 period and 8-10% from the 1960s.
Many recovered programmes, particularly those made by the BBC, have been returned as telerecordings by foreign broadcasters or private film collectors from the 1980s onwards, as the BBC has taken stock of the large gaps in its archive and sought to recover as much of the missing material as possible. Many of these surviving telerecorded programmes, such as episodes of Doctor Who, Steptoe and Son and Till Death Us Do Part continue to be transmitted on satellite television stations such as UK Gold, and many such programmes have been released on VHS and DVD.
Because videotape records at fifty interlaced fields per second and telerecordings at twenty-five frames per second, videotaped programmes that exist now only as telerecordings look more "jerky" than the originals. One solution to this problem is VidFIRE, an electronic process to restore video-type motion.
External links
- The 'Total Rewind' museum of Vintage VCR technology (http://www.totalrewind.org)