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Article is a bit disappointing. Summary: Technicolor filmed simultaneously on three B&W films after passing through color filters. Each film strip was dyed red

Article is a bit disappointing. Summary: Technicolor filmed simultaneously on three B&W films after passing through color filters. Each film strip was dyed red, green, blue, and the three were overlaid for the final film. Set lighting had to be extra bright. The ruby slippers were actually silver in the books.

titzer 5y ago
Perfect summary.
paulmd 5y ago
Yup, it's largely similar to the technique used by Prokuin-Gorskii for his photographic survey of Russia around 1900. He was using wet plates for still images rather than film for movies - but same idea. Take three monocrhome images, one of each primary color, and project them back together and you'll have a full-color image. http://www.loc.gov/pictures/search/?q=color&st=grid&co=prok http://www.loc.gov/pictures/search/?q=color&st=grid&co=prok Kind of a fun fact is that in a sense we use this same idea today for digital photography - modern camera sensors are almost entirely[0] monochrome, so we put a tiled color filter in front of the sensor, which makes each pixel pick up a different color (like the 3 colors of the film strip), and then we digitally reconstruct full color at all pixels from the individual colored-monochrome pixels. So it's basically just a 3-strip image, but shot on the same image and digitally reconstructed. https://en.wikipedia.org/wiki/Color_filter_array https://en.wikipedia.org/wiki/Color_filter_array https://en.wikipedia.org/wiki/Bayer_filter https://en.wikipedia.org/wiki/Bayer_filter [0] the exception is Foveon sensors which actually do have three sensors at each "pixel", stacked on top of each other. The problem is this generally has lower resolution than an equivalent Bayer filter-based sensor - however somewhat offset by a relative lack of moire due to the higher color resolution. Most (but not all) Bayer sensor cameras use an antialiasing filter (optical low pass filter) over the sensor to combat this - which costs some resolution (eg Sony A7 vs A7r - the base model has the moire filter and the R doesn't, but the R model gets almost twice as much resolution).
- klodolph 5y ago
  Color film works the same way, actually. Color film is "just" made up of three layers of monochromatic film, stacked on top of each other. There are color filters between each layer to filter the light. With color positive film, these layers are removed during processing. If you have a knife, you can scrape off the color layers in order. Starting from the emulsion side (the side which is less shiny), you'll scrape of the magenta layer first, then the yellow, and you'll be left with cyan on the bottom. It's always in this order, due to the physics of how film works.
  - datameta 5y ago
    Why is this the order it must be in? The order of wavelengths of light passing would be: green -> blue -> red ? Doesn't make intuitive sense to me. Can you explain?
    - Finnucane 5y ago
      According to ‘Making Kodak Film’ by Robert Shanebrook, the blue emulsion layers were on top, the red layers on the bottom (the acetate side), and the green in the middle. There was a yellow filter layer under the blue emulsion. All of the various layers of chemistry were applied to the acetate backing in one pass.
    - klodolph 5y ago
      Yeah, sorry, I mixed it up. It's been a while since I've actually done this. You scrape off yellow first (leaving blue), then magenta (leaving cyan), and finally cyan.
  - paulmd 5y ago
    Color film is similar to the Foveon sensors I was talking about, since it’s actually three different emulsions stacked on top of each other, while most digital sensors are actually monochrome with a color filter (just all color filters tiled on a single piece of film rather than three separate strips like Technicolor). Although fun fact some of the early Minolta digital SLRs (“RD-100”?) actually did have three separate sensors, and also interestingly they used telecompressors to “resize” the image down to the smaller sensor so that the lenses effective focal length didn’t get super long on the tiny sensors they could cost-effectively produce in 1993. And this also somewhat mitigated the loss of light from having to split the light across multiple sensors.
crooked-v 5y ago
Stage and film lighting even with improvements today is blazingly hot. I can only imagine what a nightmare it must have been to work under equipment of the time with triple the normal lighting.
samatman 5y ago
As an aside, the silver color of the slippers was load-bearing, if we accept Littlefield's theory about Baum slipping some sly allegory into the story. Interpreted this way, the yellow brick road is the gold standard, the silver shoes are the Silverite 16-to-1 exchange ratio of silver to gold, and Oz? Abbreviation for ounce. Evidence that this was Baum's intention is... thin, but I've always liked it. For the curious: https://en.wikipedia.org/wiki/Political_interpretations_of_The_Wonderful_Wizard_of_Oz#Monetary_policy https://en.wikipedia.org/wiki/Political_interpretations_of_T...
readbeard 5y ago
It seems Gizmodo might have gotten even that wrong. According to this (much more informative) page [0], I think they were dyed cyan (so dark areas absorb red), magenta (dark areas absorb green), and yellow (dark areas absorb blue). The Italian Wikipedia article also contains a helpful illustration [1] (missing on the English one unfortunately). [0] http://www.digital-intermediate.co.uk/examples/3strip/technicolor.htm http://www.digital-intermediate.co.uk/examples/3strip/techni... [1] https://it.wikipedia.org/wiki/Technicolor#/media/File:Technicolor4NegativoSelezioneUnicoPerCartoniAnimati.jpg https://it.wikipedia.org/wiki/Technicolor#/media/File:Techni...

titzer 5y ago

Perfect summary.

paulmd 5y ago

Yup, it's largely similar to the technique used by Prokuin-Gorskii for his photographic survey of Russia around 1900. He was using wet plates for still images rather than film for movies - but same idea. Take three monocrhome images, one of each primary color, and project them back together and you'll have a full-color image. http://www.loc.gov/pictures/search/?q=color&st=grid&co=prok http://www.loc.gov/pictures/search/?q=color&st=grid&co=prok Kind of a fun fact is that in a sense we use this same idea today for digital photography - modern camera sensors are almost entirely[0] monochrome, so we put a tiled color filter in front of the sensor, which makes each pixel pick up a different color (like the 3 colors of the film strip), and then we digitally reconstruct full color at all pixels from the individual colored-monochrome pixels. So it's basically just a 3-strip image, but shot on the same image and digitally reconstructed. https://en.wikipedia.org/wiki/Color_filter_array https://en.wikipedia.org/wiki/Color_filter_array https://en.wikipedia.org/wiki/Bayer_filter https://en.wikipedia.org/wiki/Bayer_filter [0] the exception is Foveon sensors which actually do have three sensors at each "pixel", stacked on top of each other. The problem is this generally has lower resolution than an equivalent Bayer filter-based sensor - however somewhat offset by a relative lack of moire due to the higher color resolution. Most (but not all) Bayer sensor cameras use an antialiasing filter (optical low pass filter) over the sensor to combat this - which costs some resolution (eg Sony A7 vs A7r - the base model has the moire filter and the R doesn't, but the R model gets almost twice as much resolution).

klodolph 5y ago
Color film works the same way, actually. Color film is "just" made up of three layers of monochromatic film, stacked on top of each other. There are color filters between each layer to filter the light. With color positive film, these layers are removed during processing. If you have a knife, you can scrape off the color layers in order. Starting from the emulsion side (the side which is less shiny), you'll scrape of the magenta layer first, then the yellow, and you'll be left with cyan on the bottom. It's always in this order, due to the physics of how film works.
- datameta 5y ago
  Why is this the order it must be in? The order of wavelengths of light passing would be: green -> blue -> red ? Doesn't make intuitive sense to me. Can you explain?
  - Finnucane 5y ago
    According to ‘Making Kodak Film’ by Robert Shanebrook, the blue emulsion layers were on top, the red layers on the bottom (the acetate side), and the green in the middle. There was a yellow filter layer under the blue emulsion. All of the various layers of chemistry were applied to the acetate backing in one pass.
  - klodolph 5y ago
    Yeah, sorry, I mixed it up. It's been a while since I've actually done this. You scrape off yellow first (leaving blue), then magenta (leaving cyan), and finally cyan.
- paulmd 5y ago
  Color film is similar to the Foveon sensors I was talking about, since it’s actually three different emulsions stacked on top of each other, while most digital sensors are actually monochrome with a color filter (just all color filters tiled on a single piece of film rather than three separate strips like Technicolor). Although fun fact some of the early Minolta digital SLRs (“RD-100”?) actually did have three separate sensors, and also interestingly they used telecompressors to “resize” the image down to the smaller sensor so that the lenses effective focal length didn’t get super long on the tiny sensors they could cost-effectively produce in 1993. And this also somewhat mitigated the loss of light from having to split the light across multiple sensors.

crooked-v 5y ago

Stage and film lighting even with improvements today is blazingly hot. I can only imagine what a nightmare it must have been to work under equipment of the time with triple the normal lighting.

samatman 5y ago

As an aside, the silver color of the slippers was load-bearing, if we accept Littlefield's theory about Baum slipping some sly allegory into the story. Interpreted this way, the yellow brick road is the gold standard, the silver shoes are the Silverite 16-to-1 exchange ratio of silver to gold, and Oz? Abbreviation for ounce. Evidence that this was Baum's intention is... thin, but I've always liked it. For the curious: https://en.wikipedia.org/wiki/Political_interpretations_of_The_Wonderful_Wizard_of_Oz#Monetary_policy https://en.wikipedia.org/wiki/Political_interpretations_of_T...

readbeard 5y ago

It seems Gizmodo might have gotten even that wrong. According to this (much more informative) page [0], I think they were dyed cyan (so dark areas absorb red), magenta (dark areas absorb green), and yellow (dark areas absorb blue). The Italian Wikipedia article also contains a helpful illustration [1] (missing on the English one unfortunately). [0] http://www.digital-intermediate.co.uk/examples/3strip/technicolor.htm http://www.digital-intermediate.co.uk/examples/3strip/techni... [1] https://it.wikipedia.org/wiki/Technicolor#/media/File:Technicolor4NegativoSelezioneUnicoPerCartoniAnimati.jpg https://it.wikipedia.org/wiki/Technicolor#/media/File:Techni...