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Re-creating Disney's sodium vapor process [video]

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Re: Re-creating Disney's sodium vapor process [video]

#81
post #17

It looks like Redwood City's old sodium-vapor streetlights, recently replaced with LEDs. The Golden Gate Bridge also used to use such lighting. That still looks yellow, but in 1972 the original sodium-vapor lamps were replaced with ones that required a yellow filter.

On a trip to San Diego, I ran to a grocery store one night, and had a hard time finding my car because of light like that, and I couldn't tell what any of the colors were. It's that still common out west?

Re: Re-creating Disney's sodium vapor process [video]

#82

Earlier quoted context omitted.

Near infrared isn't generated by random environmental objects. You're thinking of far infrared. Infrared is a big spectrum, much larger than the visible spectrum. It may be generated by lights but could be filtered out. It is generated by the Sun, but so is the sodium wavelength. The technique would work indoors just as well as the sodium one, but with important advantages. I think it could even work pretty well outd…

Huh, my bad, I thought thermal sources (ie. like random hot stuff, not glowing hot stuff) emitted a wide band of frequencies including near-IR, but fair enough. You'd still get it from any sort of incandescent light source right? (same as a sodium lamp) > but with important advantages What's the benefit over using any other single frequency visible light? Even if the atmosphere absorbs most of a particular band, if a…

> What's the benefit over using any other single frequency visible light?

One advantage might be to pulse the IR and detect it via that, if the detectors are sufficiently fast. Maybe have a filter that's pulsed also (Pockels cell?)

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

Re: Re-creating Disney's sodium vapor process [video]

#83
post #3

Very interesting stuff. I'm curious if this means anything in terms of good vs perfect technology or what tech wins out in practice. This process seems just plain better than green-screen, so why did it lose out? Is is just that green screen is good enough? Was it too hard to do this sodium vapor process with random cameras back in the day? Are sodium vapor lights bad enough in some way that practically it lost out?

In modern production, an army of underpaid, un-unionized visual effects contractors who pitch lowest bidder contracts to manually retouch basically every single pixel in the film six times over is a fine price to pay for studios, while this method would require carefully planning everything ahead of time, proper scripting, and not being able to change scenes after shooting nearly as easily, and also probably involves hiring unionized labor by talented tradespeople who can say "naw that's a bad deal and a dumb idea".

Re: Re-creating Disney's sodium vapor process [video]

#84
post #3

Very interesting stuff. I'm curious if this means anything in terms of good vs perfect technology or what tech wins out in practice. This process seems just plain better than green-screen, so why did it lose out? Is is just that green screen is good enough? Was it too hard to do this sodium vapor process with random cameras back in the day? Are sodium vapor lights bad enough in some way that practically it lost out?

Because it creates more problems than it solves. A movie set is expensive and moves fast – and keying is not as big of a problem as they made it out to be.

For example, Niko doesn't seem to be aware of the IBK keyer (based on his comments in the VFX subreddit), which is the keyer used on almost every shot in high-budget movies. While it's not a single-click solution, it's the main tool to tackle thousands of shots with defocused edges, motion blur, and semitransparency every year.

Niko deserves credit for bringing Paul's incredible experiment, but Corridor is at its core a group of entertainers, and most of them have never had experience in a large production/VFX environment. Take everything they present with a grain of salt.

Re: Re-creating Disney's sodium vapor process [video]

#85
post #24

I’ve been doing something similar using “cheap” Chinese band notch filters. Had no idea about this Disney process. Also using this for AI training purposes. It’s amazing what you can buy on Alibaba, fully custom frequencies.

After you using sodium vapor out a different light source?

Different frequency.

Re: Re-creating Disney's sodium vapor process [video]

#86
post #82

Earlier quoted context omitted.

Huh, my bad, I thought thermal sources (ie. like random hot stuff, not glowing hot stuff) emitted a wide band of frequencies including near-IR, but fair enough. You'd still get it from any sort of incandescent light source right? (same as a sodium lamp) > but with important advantages What's the benefit over using any other single frequency visible light? Even if the atmosphere absorbs most of a particular band, if a…

> What's the benefit over using any other single frequency visible light? One advantage might be to pulse the IR and detect it via that, if the detectors are sufficiently fast. Maybe have a filter that's pulsed also (Pockels cell?) https://en.wikipedia.org/wiki/Pockels_effect

One problem you might run into is that a lot of common plastics are opaque to NIR light, so you might find certain materials gave you strange results (water bottles that appear transparent to the eye would not actually pass the NIR light needed to make the mask layer).

Re: Re-creating Disney's sodium vapor process [video]

#87
What I find incredible is that this was done with film without modern tools such as those light meters and a preview mask on an LCD screen.

They had to do a test and then process the film for each adjustment. A extremely tedious process and that doesn't include the work that was required to produce that prism.

Re: Re-creating Disney's sodium vapor process [video]

#88
post #62
post #9

Very very cool, mindblowing actually, seems legitimately useful. There have been a few art installations over the years that use these lights: https://www.youtube.com/watch?v=hd077pa-5CI For a second I thought that the video was from this channel, which also does experimental cinematography stuff: https://www.youtube.com/watch?v=-4uzyhbDFas

Yes, extremely impressive. "Mary Poppins" rightfully received an Oscar for best visual effects. I am continuously amazed at the level of innovation done at the Disney studios back when Walt Disney was still alive. Rewatching Snow White with my daughter a few months ago, I was flabbergasted by the animation quality, even when compared to animation movies made decades later. Just look at these water scenes: https://you…

It's not that they forgot how the multiplane worked. They understood it...in theory. However, they were quirky beasts and it was knowledge of those quirks that was lost. Like getting an old car to run--most people these days don't know about pumping the gas pedal to keep it running.

Re: Re-creating Disney's sodium vapor process [video]

#89
A bit light on the detail of how the standard green-screen process works in post: I'd prefer a bit deeper dive into the problems one encounter. And then compared harder to how this became easier with the sodium lights, compare and contrast. I think that was glossed over too fast. Otherwise really interesting!

Re: Re-creating Disney's sodium vapor process [video]

#90
post #45

Earlier quoted context omitted.

[flagged]

I don't know, when Nico gets excited about a project, I suspect it's genuine. It's part of why I watch the channel. His employees, (Wren especially), give off a silly fake enthusiasm vibe (or maybe he's just like that, and that's why he got hired, I don't know) but Nico only really shows up in the videos he wants to make. Guy seems like he's getting to live out his dream. The videos he spearheads are both technically…

I've been watching these guys for so long — when Wren's speaking to camera in his solo videos he overdoes it but I think he's naturally pretty excitable. Niko is my favorite though.
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