4 ms·

Because you want color bands that you control, not that are naturally emitted.

• modeless 3y ago
  Near infrared isn't naturally emitted by room temperature objects. You're thinking of far infrared.
  • ikiris 3y ago
    I didn't say room temperature objects. I said naturally emitted. Trying to have lights and other objects involved in film production that don't have emission spectra inside the mask range for near infrared would be a lot of effort compared to just... not having it be a problem with things that are easily attained with cheap materials like sodium narrowband.
    • modeless 3y ago
      By that definition the sodium wavelength is naturally emitted too. The sodium vapor process as implemented in the video requires special lights that don't emit the sodium wavelength. It's actually much harder to do that (and it affects color reproduction too) than to block some infrared from existing lights. Infrared blocking film and filters are readily available and cheap. They don't need to be fancy narrowband notch filters like a sodium wavelength filter would have to be. Now that I think about it, Disney must have done something pretty special for the lighting in the foreground in their version of the process. They didn't have single wavelength LEDs back then. I wonder how they did it?