Mass Media & Technology

Help with recording video over HDMI

(February 2021)

This site closed in March 2021 and is now a read-only archive
NG
noggin Founding member
Neil Jones posted:
james-2001 posted:
I wonder if there'll ever be a way we can get data off magnetic media without needing the original players like we've done with records and the likes? Would help massively with saving contents from obsolete media.


Didn't they already do that? Wasn't there an episode or two of Morecambe & Wise from the 1960s that had fallen through the wiping machine years ago and the only existing copy was some tatty old print that was beyond economic repair and you couldn't even look at in case it fell to pieces? Or was that a film/telerecording?


That was a telerecording on film that had gummed together I think.
LL
Larry the Loafer
They've salvaged a little bit of it didn't they?
NJ
Neil Jones Founding member
Larry the Loafer posted:
They've salvaged a little bit of it didn't they?


Morecambe & Wise? They salvaged the lot I believe, wasn't it the 1968 Christmas Special?



Actually I might have mixed this up something else?
Last edited by Neil Jones on 9 March 2021 2:49pm
IN
intracube
Larry the Loafer posted:
They've salvaged a little bit of it didn't they?

Yep - from part 2: https://www.bbc.co.uk/rd/blog/2017-12-morecambe-wise-video-xray-microtomography
*
Last edited by intracube on 9 March 2021 2:56pm
IJ
IanJRedman
That's a fascinating but tragic story. Found by the same guy who retrieved nine missing Doctor Who film prints from Nigeria, circa 2011.
VM
VMPhil
The real tragedy with that story is… *whispers* those shows weren't very good. But for some reason they continue to repeat them at Christmas, even the one with 'The IRA Sketch'
IJ
IanJRedman
VMPhil posted:
The real tragedy with that story is… *whispers* those shows weren't very good. But for some reason they continue to repeat them at Christmas, even the one with 'The IRA Sketch'

Well, those were a separate find - the ruined M&W print was from Nigeria, whereas the other two returned episodes were from Sierra Leone IIRC. But yes, I definitely preferred the first episode in that Lost Tapes special (the IRA sketch was in the second).
NG
noggin Founding member
Yes - I think two different situations are being discussed here.

1. The film tele-recording that had fused together and was unplayable via normal Telecine routes (it was basically a fused lump) - so advanced X-ray techniques were used to 'look inside' the solid lumps.

2. The B&W film tele-recordings that were discovered that were entirely playable on a normal Telecine, and had 'chroma dots' (i.e. the PAL colour subcarrier that carries the colour information in a composite video signal hadn't been filtered out) on the B&W film recording that 'colour recovery' processes were able to decode to recreate the colour information (this technique also allows the geometric distortion that the telerecording process introduced to be undone)
IN
intracube
noggin posted:
2. The B&W film tele-recordings that were discovered that were entirely playable on a normal Telecine, and had 'chroma dots' (i.e. the PAL colour subcarrier that carries the colour information in a composite video signal hadn't been filtered out) on the B&W film recording that 'colour recovery' processes were able to decode to recreate the colour information (this technique also allows the geometric distortion that the telerecording process introduced to be undone)

I only remembered this technique being used to restore the colour on a single Dad's Army telerecording, but can see from this article it's been used quite a bit since: https://en.wikipedia.org/wiki/Colour_recovery

Impressive software for it to be able to cope with the film registration errors (wobble) and any distortions from the telerecording.
MI
Michael
Wasn't the chromadot technique also used for Episode 3 (or is it 4?) of Planet of the Daleks?
NG
noggin Founding member
intracube posted:
noggin posted:
2. The B&W film tele-recordings that were discovered that were entirely playable on a normal Telecine, and had 'chroma dots' (i.e. the PAL colour subcarrier that carries the colour information in a composite video signal hadn't been filtered out) on the B&W film recording that 'colour recovery' processes were able to decode to recreate the colour information (this technique also allows the geometric distortion that the telerecording process introduced to be undone)

I only remembered this technique being used to restore the colour on a single Dad's Army telerecording, but can see from this article it's been used quite a bit since: https://en.wikipedia.org/wiki/Colour_recovery

Impressive software for it to be able to cope with the film registration errors (wobble) and any distortions from the telerecording.


Yes - the chroma dots actually help you reverse the warping introduced by the film recording (as you can use them to 'undo' some of the geometric errors introduced by that process)
IJ
IanJRedman
noggin posted:
intracube posted:
noggin posted:
2. The B&W film tele-recordings that were discovered that were entirely playable on a normal Telecine, and had 'chroma dots' (i.e. the PAL colour subcarrier that carries the colour information in a composite video signal hadn't been filtered out) on the B&W film recording that 'colour recovery' processes were able to decode to recreate the colour information (this technique also allows the geometric distortion that the telerecording process introduced to be undone)

I only remembered this technique being used to restore the colour on a single Dad's Army telerecording, but can see from this article it's been used quite a bit since: https://en.wikipedia.org/wiki/Colour_recovery

Impressive software for it to be able to cope with the film registration errors (wobble) and any distortions from the telerecording.


Yes - the chroma dots actually help you reverse the warping introduced by the film recording (as you can use them to 'undo' some of the geometric errors introduced by that process)

Yes, it's a lovely side-effect of the process - the colour recovery software knows the correct pattern of the dots, so it can use them to undistort the film recordings. Distortions were mainly caused by the curved screen of the film recorder IIRC.

Michael posted:
Wasn't the chromadot technique also used for Episode 3 (or is it 4?) of Planet of the Daleks?

Yes, Episode 3, and numerous other episodes too. The Mind of Evil (one episode hand-colourised and the other five from chromadots) has just been re-released on a Blu-ray set last week.

Newer posts