OT: BBC videotapes (Was: DIY Kryoflux or Catweasle

[Fred Cisin]

>> Fortuitously, the B&W film was sharp enough to be able to make out the dot
>> mask of the CRT! That made possible the development of a new technique -
>> computer recognition of which pixels were the original RGB dots of the image!
>> That, unlike manual colorisation, results in reasonably exact recreation of
>> the original colors.

On Fri, 26 May 2017, Peter Corlett wrote:
> I don't know if you're describing yet another way colour was retrieved from
> telecine recordings,
possibly
> or a faulty recollection of the detail of James Insell's
> work at BBC R&D.

much more likely.
Thank you.
My information is fourth hand, from something discussed on a TV talk show.
(typical unreliable source!)

> James's moment of inspiration was when he was watching some old Doctor Who
> telerecordings that had been telecined back and had caused what appeared to be
> artifact colour. He realised that the film recording contained enough detail to
> capture the colour subcarrier.
> The bit that was combined genius and perspiration was figuring out the phase of
> the colour signal, since the colour burst never made it into the recording.
> Without that, one can't reliably separate U from V and the hue will be
> essentially random.

http://icolorist.com/dr-who-restoration-by-enthusiasts/
http://www.techmind.org/colrec/
Have some discussion of details.

We should be grateful that they developed those RE-colourisation 
techniques and didn't stick with the USA ("Legend"?) 
computer assisted manual Ted Turner style colorization.


--
Grumpy Ol' Fred     		cisin at xenosoft.com