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-   -   Recreating the look of tube cameras (https://www.dvinfo.net/forum/open-dv-discussion/498669-recreating-look-tube-cameras.html)

Brian Drysdale July 29th, 2011 03:04 PM

Re: Recreating the look of tube cameras
 
On the moving image it would be moving randomly.

David Heath July 29th, 2011 03:20 PM

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

Seymour Clufley July 29th, 2011 05:30 PM

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?

Seymour Clufley July 29th, 2011 09:52 PM

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.

Brian Drysdale July 30th, 2011 01:19 AM

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.


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