Re: Recreating the look of tube cameras
 

My recall of "ringing" was in B/W television, not colour but here in Western Australia, we were late bloomers for colour TV, 1975 ?? where I was living at the time. As for Blake's 7 and the other good productions of the era, I would not have noticed any ringing or other problems as I was too much into the storystuff in them.

Re: Recreating the look of tube cameras
 

No - what you're seeing there is a registration error, a discrepancy between the way the scans of the 3 (or 4 ) tubes are aligned.
It's a bit too small an image to see much online, but it doesn't really appear to show very much. The effect Robin refers to is on such as a vertical edge between such as a nearly white block (say 90 IRE) and a dark grey one - you'd typically see (left to right) plain 90% white, brief 100% white line, followed by brief 0% black line, then plain 10% dark grey. The effect is as if a line had been drawn round high contrast objects.

But it was adjustable, and on location drama deliberately taken to quite low settings. It would typically be set to higher levels on such as LE or sport to give a more "punchy" look.
Have you tried what I suggested quite a long time ago? Split the luminance and chrominace images (to give Y,U,V) then apply a soften filter to the chrominance (U and V), and recombine. The effect is a still sharp luminance image, but with the colour looking a bit as if painted in, a little like a childs colouring book. Just don't overdo it.

Re: Recreating the look of tube cameras
 

Yes, I did this in After Effects using R,G,B,Y. Some test images were posted a few days ago now.

However, reading your suggestion again, I thought about doing it with the YUV model as you state. (Thanks for reminding me about YUV!)

AfterEffects can't seem to work in YUV - at least, not to do what we need - so I wrote a program instead. Here are some results:

Oliver Stone

Bill Nighy

In each case, the images are...

LEFT: raw image
MIDDLE: YUV remixed (as David describes)
RIGHT: YUV remixed + chrominance noise added

To be honest I'm quite pleased with these results. It's surprising how much more "convincing" it is with the noise added. Clearly, though, the noise is only "first version" and can be improved. The dots need to be smaller, for starters.

Does anyone have any other ideas? Should the noise be less colourful? Should it be confined to (or exaggerated in) dark areas?

Re: Recreating the look of tube cameras
 

I'd keep any noise to the dark areas, it tends to look digital and I don't think the video engineers of the period would've accepted that level of noise on faces.The noise would've been random rather than fixed pattern.

Re: Recreating the look of tube cameras
 

Brian, the noise in my example is completely random. Can you be more specific? Does it look like it's fixed pattern?

Re: Recreating the look of tube cameras
 

On the moving image it would be moving randomly.

Re: Recreating the look of tube cameras
 

You would also not get "splodges" due to noise. It normally looks like much smaller dots, but even if more low frequency in nature it will then look more like "horizontal lines" owing to way the scanning works

Re: Recreating the look of tube cameras
 

I've been watching a DVD of a show from 1971. I've been pausing individual frames and watching what happens to the grain.

Please bear in mind I'm not sure if there is any difference between "noise" and "grain".

What seems to happen all over the image, especially in dark areas but in bright areas too, is a mottled effect which "evolves" from one frame to the next.

This image, for example. Look at the dark red chair behind the woman. Apart from the overall vertical gradient (dark>bright>dark), there are tiny "grains" - some brighter and some darker. It's the same on the woman's cheek, or the dark part of her arm.

Is this an artefact of MPEG compression or is it part of the original tube image? (Unfotunately I don't have uncompressed tube footage.)

I notice in the very dark areas (black, pretty much) there is no grain or noise. I'm not sure what that means - grain should be confined to dark areas but not extremely dark areas?

Re: Recreating the look of tube cameras
 

I've been working on my program again tonight, and would appreciate feedback on the current state of it.

Here are three images. The raw version is on the left, the processed version on the right.

One
Two
Three

These images are large so unfortunately you have to scroll the page to see the whole thing. I'll output smaller images next time.

I googled for images of actors in theatre, so as to get overhead lighting. The third image is a photo I took of a forest, and in this case I don't think the "processing" is terribly successful.

Re: Recreating the look of tube cameras
 

Having watched some 1970's Top of the Pops material last night, the colours are rather desaturated compared to modern material as David suggests: 4:1:0 or less. There's perhaps almost a sense of the overlying B&W from the luminance tube in the EMI 2001.

BTW Feature films that over lie B&W on colour include Moby Dick in 1956, which was the first film to do so. Although the look I'm thinking about on the EMI 2001 is more subtle, tending to very softly mute the colours.