The story is one of a number that do not exist in the BBC Archives in full colour; though an off-air camera copy exists, this does not provide a good signal for recreating a colour version as seen in the DVD release Doctor Who And The Silurians (details of that process may be read from the Restoration Team's Beneath the Surface article). A new colour decoding strategy was deployed for episode three of the Planet of the Daleks DVD release (see article), and has now reached maturity to tackle the third Doctor's third adventure:
Their method is a refined version of that trialled on the 2009 Planet of the Daleks re-release; it is now being deployed on a seven-part 1970 Jon Pertwee adventure, The Ambassadors of Death. "It seemed on most recordings, they didn't filter off the colour carrier [encoded as a 'chroma dot' pattern in each frame], which for the last few decades has been nothing more than an annoyance." Team member Richard Russell used the signal to reverse-engineer raw colour pictures that could be retouched frame by frame. "It's very, very labour intensive -- several hundred man hours' work every episode," says Steve Roberts. Luckily, a new "quadrant editor" is helping them to produce better source material upfront, so they hope to deliver the Ambassadors episodes to the BBC within weeks.
No other details on the future DVD release is known at present, though a commentary for the story was recorded back in late 2009, featuring members of the cast and crew including Nicholas Courtney (The Brigadier), Terrance Dicks (script editor), Peter Halliday (alien voices) and Derek Ware (stunts/fight arranger).
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