ON LOCATION: YOU'VE BEEN FRAMED
Geoff Stafford meets the man who tweaks viewers' clips for Granada Television's programme of home-video mishaps
(First published in 1991)
In under a year, You've Been Framed! has blossomed from a one-off pilot into a peak-time, ratings-grabbing series.
With viewer's clips currently arriving at the rate of two hundred each day, how does home-video make the transition to broadcast television?
Brian Thomas is the Technical Supervisor on the show: "VHS-C is the most popular format among the tapes we receive," he says. "We get the odd full-size VHS, but very few Video-8. We are just starting to receive S-VHS."
No Hi-8? "Hopefully not, he laughs. "The players are none-existent. If a Hi-8 tape arrived, we would have to play it on a camcorder."
The team has even received some Betamax tapes. Although this format is well on the way out as far as the home-user is concerned, it is now making inroads into broadcast television. Albeit it in its much upgraded professional reincarnation: Betacam SP.
Every studio at Granada is equipped with up to three Betacam SP VCRs. The format is used for off-line editing and extensively in the making of You've Been Framed!
After a preliminary selection, Brian spends a day transferring about 300 British clips onto a single Betacam SP tape. Any enhancement necessary is carried out during this process.
According to Brian, the main problem is instability and he illustrates his point with a viewer's tape which has just arrived. This is played directly into one of the control-room monitors. The results are unviewable; the top half of the picture jittering and 'hooking' (bending) over to one side.
"Domestic televisions have all kinds of circuitry in them," he explains. "Including a flywheel circuit which keeps the picture perfectly OK — even if a few tape syncs are missing. Monitors don't have this; so they show up every flaw. We couldn't record that onto SP, or any other broadcast VTR, without correction.'
Feeding the output of his workhorse — a £3000 JVC S-VHS machine — through a FOR A FA310P digital time-base-corrector, cures the instability in this, and most, cases. However, serious 'wobbles' can be impossible to correct.
"I'd recommend this particular time-base-corrector to any reader who is thinking of buying one," says Brian. "They're excellent — though not actually of broadcast standard." Facilities include still-frame and S-connectors for the hi-band formats. The price is in the region of £1200.
He loads another newly-arrived tape, but it seems to be blank. The JVC refuses to play another. He concludes that the tape is faulty, but that a more ordinary VCR would probably play it. It is, he says, yet another example of the less-forgiving nature of professional quality equipment.
Another of the biggest problems is colour. Shots often have an unpleasant colour cast, caused because people have failed to white balance them correctly. Using a colouriser — a Vidigrade unit from a Rank Cintel telecine machine — Brian is able to adjust the red, green and blue parts of the signal, until the colour is correct.
Other adjustments are possible too. A gain control amplifies the picture, brightening it and putting detail into dark areas. The gamma — the tonal contrast of the scene — can be stretched or compressed. Using lift, the tones can be moved up or down the tonal scale.
By watching a waveform monitor (oscilloscope) — a standard piece of equipment in any television studio — Brian is able to ensure that, despite these adjustments, the video signal is kept within the peak white and black levels — the points at which parts of the picture burn out to white or become a solid black.