Colourising Monochrome Film

[chessteruk]

I have heard that all the information for matching the original colours is often already stored in monochrome film. Thus allowing authentic colourisation. Is this true and how does it work? Thanks.

[jno]

I'd have thought not; mono film has brightness but not hue. Film studios who want to colourise old black and white film can usually only guess. Still, someone may come along and prove me wrong.

[Buenchico]

As Jno suggests, b&w film doesn't respond differently to the various wavelengths of light (making up colours) but only to their combined amplitudes. So there is no direct record of colours.

The actual process used is described here:
https://en.wikipedia.org/wiki/Film_colorization#Digital_colorization

[Old_Geezer]

That's wonderful: almost as good as when a photographer takes the hat off of someone in the photograph and sees what hairstyle they had at the time. It's amazing what they can do with technology these days.

[jno]

very rarely, a cinema film may be filmed in colour but shown in black and white for artistic reasons. Wikipedia names The General and The Man Who Wasn't There as two of them.

https://en.wikipedia.org/wiki/Black_and_white

You can do the same thing with a photo on Photoshop, turning a colour picture into mono. But most mono films really are mono.

[ivor4781]

according to the excellent BBC doc on the first tv transmission last night on bbc4 then yes the colour info is stored on b/w film (somehow). they restored a b/w film of theirs into colour using this info

[Old_Geezer]

http://www.radiotimes.com/tv-programme/e/ffhymj/televisions-opening-night-how-the-box-was-born

[vulcan42]

However unlikely, it seems it's true.
https://www.theguardian.com/technology/2008/dec/11/digital-video-restoration-dad-s-army

[mikey4444]

Vulcan....very interesting Guardian article !

Thanks !

[Old_Geezer]

"Even though it was originally recorded on early colour videotape."
I'd suspect it isn't something every B&W film can achieve. It's something that was retained during a conversion.

[dannyk13]

I don't know how it was done,but in 1954 my wedding photos were taken in black and white and when we got them back two of them were in authentic colour.

[woofgang]

OG, they may be able to mock up the hairstyle from the bits that can be seen before the hat is removed, but sadly they have absolutely no way of knowing, just from the photo, what is under the hat.

[jno]

OG, yes, that was something made in colour that had been incompletely turned into black and white. I think if something was made in black and white, there's nothing to restore; you can colourise it but only by guessing.

Fasinating, though, I'd not seen that article.

[chessteruk]

Thank you everyone for your replies. Definitely food for thought.