This Invention Made Disney MILLIONS, but Then They LOST It!

Corridor Crew
7 Apr 202412:25

Summary

TLDRThe video script discusses the revival of a superior visual effects technology from the 1960s, invented by Disney, which outperforms the green screen. Known as the sodium vapor process, it utilizes a specific yellow spectrum and unique beam splitter prism to create flawless compositing without the common issues of green screens. Dr. Paul Debevic recreated this lost technology, enabling the first test in over 30 years. The experiment demonstrates the process's ability to handle challenging subjects, like a clown on Mars, with remarkable results, sparking a discussion on the potential of this technique in modern visual effects.

Takeaways

  • 🎬 The discussion revolves around the comparison between the old sodium vapor process and the modern green screen technology in visual effects.
  • 🌟 The sodium vapor process, invented by Disney in the 1960s, was considered superior to green screen as it allowed for more intricate and seamless compositing.
  • 🚫 One of the main issues with green screen is that it cannot handle blurry or transparent objects and matching colors can cause problems, which the sodium vapor process seems to overcome.
  • 🔍 Dr. Paul Debevic is introduced as an expert who has recreated Disney's lost prism, which was a key component of the sodium vapor process.
  • 💡 The sodium vapor process works by using a specific wavelength of yellow light (589 NM) and a beam splitter prism to separate this wavelength from the rest of the spectrum for compositing.
  • 📸 The process involves filming the subject and the background separately and then using a hold-out mat to combine them without double exposure.
  • 🎥 The recreation of the sodium vapor process was done using off-the-shelf components and two cameras instead of the original two strips of film.
  • 🌐 The test of the recreated sodium vapor process after 30 years was successful, showing no spill, edge feather, or mat lines in the final composite.
  • 🤖 The advancements in compositing tools, including machine learning, are still in need of training data, and the sodium vapor process could provide valuable data for this.
  • 🎞 The sodium vapor process, while not widely used today, still holds potential as a gold standard for achieving perfect transparency in compositing and visual effects.

Q & A

  • What is the fundamental building block of visual effects in movies?

    -The fundamental building block of visual effects in movies is the ability to layer one moving image over another, which is primarily achieved through techniques like green screen or blue screen.

  • What are some of the problems associated with using green screen technology?

    -Problems with green screen technology include the inability to film blurry or transparent objects, issues with wearing clothes the same color as the screen, and color spill that can ruin footage.

  • What technology did Disney invent in the 1960s that was superior to green screen?

    -In the 1960s, Disney invented the sodium vapor process, which used a specific spectrum of yellow light from a low-pressure sodium vapor light and a beam splitter prism to achieve visual effects without the limitations of green screen technology.

  • How did the sodium vapor process differ from green screen technology?

    -The sodium vapor process differed from green screen technology in that it used a specific wavelength of yellow light (589 NM) and a beam splitter prism to separate and combine images without the need for chroma keying, thus avoiding issues like color spill and mat lines.

  • Why is the sodium vapor process not widely used today?

    -The sodium vapor process is not widely used today because the custom prisms required for the process were expensive and difficult to produce. Disney was only able to produce one prism, and the technology was eventually lost.

  • How did Dr. Paul Debevic contribute to the recreation of the sodium vapor process?

    -Dr. Paul Debevic contributed to the recreation of the sodium vapor process by understanding the science of light and using off-the-shelf components to recreate the physics of the process. He used two filters and two cameras instead of the custom beam splitter and film strips.

  • What was the result of the first test of the sodium vapor process in over 30 years?

    -The first test of the sodium vapor process in over 30 years resulted in a successful composite, demonstrating that the process could still produce high-quality visual effects without the issues typically associated with green screen technology.

  • How does the sodium vapor process handle transparency and motion blur?

    -The sodium vapor process handles transparency and motion blur exceptionally well, as it does not rely on chroma keying. This results in a clean composite without the need for manual adjustments or the removal of spill, bias, or other common green screen issues.

  • What are the potential applications of the sodium vapor process in modern visual effects?

    -The potential applications of the sodium vapor process in modern visual effects include any scenario where traditional green or blue screen technology faces limitations, such as scenes with transparent objects, complex lighting, or intricate details that are difficult to key out.

  • How does the sodium vapor process compare to newer compositing techniques like machine learning?

    -While newer compositing techniques like machine learning continue to improve, the sodium vapor process offers a unique advantage as a step towards perfect transparency and compositing. It provides a gold standard for visual effects, especially in situations where machine learning may lack the necessary training data for complex scenes.

Outlines

00:00

🎬 The Rediscovery of Disney's Sodium Vapor Process

This paragraph delves into the history and revival of a superior visual effects technology from the 1960s, invented by Disney. The technology, which overcomes many limitations of the green screen, involves the use of a sodium vapor light to create a unique spectrum of yellow. This spectrum allows for the separation of one specific wavelength of light, enabling the layering of moving images without the common issues associated with green screen technology. The paragraph discusses the challenges of replicating the technology due to the custom nature of the prisms used. However, Dr. Paul Debevic managed to recreate the process using off-the-shelf components, marking the first test of this technique in over 30 years. The results demonstrate the potential of the sodium vapor process in modern filmmaking, showcasing its ability to handle complex scenes such as a clown getting married on Mars, which would be difficult to achieve with traditional green screen methods.

05:00

🤹‍♂️ The Quest for the Perfect Compositing Technique

The second paragraph focuses on the quest for the perfect compositing technique in film production. It highlights the challenges faced when trying to create visual effects with green screen technology, such as issues with transparency, color spill, and the need for extensive post-production work. The paragraph introduces a character concept that has been deemed impossible to execute by production companies due to these challenges. However, with the rediscovered sodium vapor process, the filmmakers attempt to bring this character to life, showcasing the potential of the technology to revolutionize visual effects by eliminating common green screen problems. The paragraph emphasizes the importance of achieving a seamless composite, and the excitement around the potential of the sodium vapor process to change the landscape of visual effects.

10:01

🚀 Achieving the Impossible with Sodium Vapor

The final paragraph showcases the successful application of the sodium vapor process in creating a complex visual effect scene. It describes the process of filming a clown getting married on Mars, a scenario that would typically be very challenging with green screen technology. The paragraph details the technical aspects of the shoot, including the use of a spectral light meter to ensure proper lighting and the careful setup to avoid any sodium vapor light spill on the subject. The results of the shoot are astounding, with the sodium vapor process delivering a clean and seamless composite without the need for extensive post-production adjustments. The paragraph concludes with a discussion on the practicality and potential of the sodium vapor process in today's filmmaking environment, where flexibility in post-production and the use of machine learning in compositing tools are highly valued.

Mindmap

Keywords

💡Visual Effects

Visual effects refer to the manipulation, creation, or alteration of images in film, television, and other media to produce a desired outcome that cannot be achieved during live-action shooting. In the video, visual effects are discussed in the context of historical advancements, comparing old techniques to modern ones like the green screen, and exploring the potential of the sodium vapor process as a superior alternative.

💡Nostalgia

Nostalgia is a sentimental longing or wistful affection for the past, typically for a period or place with happy personal associations. In the context of the video, nostalgia might influence one's perception of older visual effects, leading to a belief that they were superior, despite advancements in technology.

💡Green Screen

A green screen, also known as a chroma key screen, is a technology used in film and photography to replace the background of a subject with a different scene or image. It involves shooting the subject in front of a solid green-colored background, which is then digitally removed to allow for the insertion of other visual elements. The video discusses the limitations and problems associated with green screen technology.

💡Sodium Vapor Process

The sodium vapor process is an old visual effects technique invented by Disney in the 1960s, which used a specific spectrum of yellow light from a low-pressure sodium vapor lamp to create a separation between the subject and the background. This process allowed for the layering of images without the common issues associated with green screen technology.

💡Chroma Keying

Chroma keying is a visual effects technique that involves replacing a specific color, typically green or blue, in a video frame with another image or scene. It is widely used in film and television production to create composites by separating the subject from the background using color hues. The video discusses the challenges and limitations of chroma keying with green screens.

💡Yellow Screen

The yellow screen, as mentioned in the video, is a part of the sodium vapor process used for visual effects. It is not an actual yellow screen but rather a specific wavelength of yellow light produced by a low-pressure sodium vapor lamp, which is used to create a separation between the subject and the background for compositing.

💡Beam Splitter Prism

A beam splitter prism is an optical device that divides incoming light into two or more separate beams. In the context of the sodium vapor process, the beam splitter prism was used to split the light coming through the lens onto two strips of film simultaneously, allowing for the creation of a composite image without the need for modern chroma keying techniques.

💡Color Spill

Color spill, also known as color contamination, occurs when light from a colored background, such as a green screen, reflects onto other objects or subjects in the scene, causing unwanted coloration. This can be a significant issue in visual effects compositing, as it can make it difficult to separate the subject from the background cleanly.

💡Composite

In the context of visual effects, a composite is the final image created by combining multiple elements or layers of footage or images. This process involves techniques like chroma keying, where a background is replaced with another image, or the sodium vapor process, which allows for the layering of images without the typical issues associated with modern compositing methods.

💡Lost Technology

Lost technology refers to knowledge or techniques from the past that have been forgotten or are no longer in use. In the video, the sodium vapor process is an example of a lost technology in visual effects, which was once considered superior to green screen technology but has since been largely forgotten.

💡Recreated Technology

Recreated technology involves reviving or reconstructing a previously existing technique or invention that has been lost or forgotten. In the video, Dr. Paul Debevic managed to recreate Disney's lost prism, which was a crucial component of the sodium vapor process, allowing for the first test of this technology in over 30 years.

Highlights

Disney's invention in the 1960s of a technology superior to the green screen is discussed.

The technology allowed layering of moving images without the limitations of green or blue screens.

Problems with green screens, such as not being able to film blurry or transparent objects, are highlighted.

The 1964 movie showcasing the technology broke chroma key rules without using computers.

The sodium vapor process used a specific spectrum of yellow light and a beam splitter prism.

The process could block one wavelength of light without affecting other colors in the scene.

The sodium vapor process was not widely adopted due to the complexity and cost of producing the prisms.

Paul Debevic recreated Disney's magic prism using off-the-shelf components.

The recreation of the sodium vapor process was the first test in over 30 years.

The experiment aimed to replace the background of a scene with a clown getting married on Mars.

The sodium vapor process provided a perfect matte with no spill, bias, or fringe issues.

The results showed excellent compositing, including motion blur and color exposure correction.

The experiment was successful, with the sodium vapor process living up to its potential.

The potential of using the sodium vapor process as a step towards perfect compositing is discussed.

The experiment demonstrated the gold standard for transparency in compositing and visual effects.

Transcripts

00:00

do you ever feel like visual effects in

00:01

old movies were better what if I told

00:03

you that wasn't just Nostalgia speaking

00:04

back in the 1960s Disney invented a

00:06

technology that was in many ways

00:08

superior to the green screen but that

00:09

Tech has long since been forgotten and

00:11

what if I told you that we found a way

00:12

to recreate

00:13

[Music]

00:16

it being able to layer one moving image

00:18

over another is the fundamental building

00:20

block of visual effects every single

00:22

crazy effect shot from every movie you

00:24

love relies on this basic core technique

00:27

and the primary way we do that is with

00:29

green screen or blue screen but there

00:31

are lots of problems with green screen

00:32

even in this modern era you can't film

00:34

blurry or transparent things you can't

00:36

wear clothes that are the same color as

00:38

the screen and the spill of the color

00:40

often times ruins footage if I want to

00:42

make a movie about a clown wearing all

00:44

the colors of the rainbow getting

00:45

married on Mars I can't that bothers me

00:48

if I could get my hands on an invention

00:50

that didn't have any of these issues it

00:52

would be like a filmm superpower it

00:54

would be like magic do you really think

00:56

so what's special about that app it's

00:58

transparent it's arent

01:01

transparent I thought the stuff I was

01:02

seeing on screen was impossible they're

01:04

keying a veil they're keying salt smoke

01:07

they're even wearing blue and green

01:09

clothes this movie from 1964 broke every

01:12

rule of chroma and they did it all

01:14

without computers so how do they do it

01:15

to explain the science behind the magic

01:17

we are joined by Dr Paul debevic the

01:19

sodium vapor process instead of a blue

01:23

screen or a green screen they used what

01:25

was sometimes called a yellow screen

01:27

there a very specific spectrum of yellow

01:30

made from a low press sodium vapor light

01:32

that puts out one wavelength of light at

01:35

589 NM because it's just one wavelength

01:39

and because of how drro filters work you

01:41

can actually block just that one

01:44

wavelength or let just that one

01:46

wavelength go through so the magic of

01:48

the sodium vapor process is they used a

01:50

beam splitter prison so that the light

01:52

that comes through the lens gets split

01:55

onto two strips of film at the same time

01:57

the sodium vapor wavelength of 589 NM

02:00

reflects out this way and all the rest

02:02

of the spectrum goes through and can

02:04

expose a color image of the actor and

02:07

that's exactly what you need to get your

02:09

map what's kind of magical about it is

02:11

that you can block that one wavelength

02:14

of yellow without messing up all of the

02:16

other colors in that scene there's no

02:19

mat lines he's motion bluring he's

02:20

dancing around the compositing is

02:23

impeccable yeah it's perfect you

02:24

couldn't have gotten such great blur

02:26

over the alpha Channel with a green

02:28

screen or a blue screen seems too good

02:30

to be true why are we not still using

02:32

this technology today yeah really what

02:34

gives because they were never able to

02:36

replicate prism what I've read that

02:38

Disney was only able to produce one

02:40

prism is that true they had to join two

02:42

pieces of glass and then have layers of

02:45

material with different indices of

02:46

refraction it's a very custom job and it

02:48

would probably cost tens of thousands of

02:50

dollars at a minimum apparently there

02:51

were three of these ever made and

02:54

also we don't know where any of these

02:56

prisms are

02:57

today and that means I'm never going to

03:00

get to answer this Burning question I

03:01

have is sodium vapor better than Green

03:03

Screen the science the physics they all

03:05

tell me it is but because the prisms

03:07

have been lost the time I'm never going

03:08

to get to realize my dream of a clown

03:10

getting married on Mars and then one day

03:13

I got a message from Paul debevic he had

03:15

done what I thought was impossible he

03:17

had recreated Disney's Magic prism and

03:19

he needed somebody to test it out this

03:21

will be the first test of the sodium

03:22

vapor process in over 30 years well I

03:26

guess this is like our hello world of

03:27

sodium vapor matting we've got our color

03:30

image and our sodium vapor image there

03:32

there it is look at that that's the idea

03:34

it's working the first thing you need

03:35

are some sodium vapor lights so

03:37

thankfully they still make the bulbs

03:39

eventually after we've had these on for

03:40

10 minutes they'll start glowing that

03:42

color I think it's working and then

03:43

we've got a couple of LED lights here

03:45

that are going to illuminate the actor

03:47

so favor mats woohoo hey pretty sweet

03:51

how is this working how did Paul debevic

03:53

manage to resurrect Disney's lost prism

03:56

well with a deep understanding of the

03:57

science of light and a little bit of C

04:00

ity I'll do a beam splitter but I'll

04:01

just do a regular beam sweit like this

04:02

beam splitter and then we'll filter the

04:04

light after it comes out of the prism

04:05

Paul recreated the physics of the sodium

04:07

Vaper process but he did it with all

04:09

off-the-shelf components instead of a

04:11

custom beam splitter he used two filters

04:14

and instead of two strips of film he

04:15

just used two cameras yeah if you ever

04:17

think your rigs are janky they're all

04:20

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click away all right now let's find out

05:19

what I'm going to do with all these hard

05:20

Tokey clothes Paul I would like to tell

05:22

you about this character every time I

05:24

approach a production company with it

05:25

they're like no can't do it it's

05:26

impossible okay and it's a story about a

05:28

clown that's trying to get

05:31

married you look so dumb me what look

05:35

I've heard big things about this magic

05:36

Crystal okay but this is ridiculous

05:39

that's impossible to key look at that I

05:42

hate to break it you but this video is

05:43

going to be a disappointment JC H feel

05:44

free to come on out it's my wedding day

05:47

oh my

05:48

God that would be difficult to key

05:50

wouldn't it it would I forgot to mention

05:51

that uh the Clown's getting married on

05:53

Mars hence the need to replace the

05:54

background oh of course yeah I think

05:56

this is going to be fantastic now I

05:57

suppose we should uh clean up the

05:58

lighting yeah kill all of the Full

06:01

Spectrum Lighting we need that one

06:02

covered yeah I need to cover one of the

06:04

skylights so that we don't have all this

06:05

like daylight spill coming in it's and

06:08

my dress is like marily been rowing

06:10

right now keep this side down it's the

06:13

best the clown can do so as you can see

06:15

right now we're spending a lot of time

06:16

getting these flags up because what we

06:18

don't want to have happen is we don't

06:20

want the sodium vapor light to be

06:21

hitting JC at all cuz then it's going to

06:23

be basically turning her transparent so

06:25

this is a spectral light meter it tells

06:27

you the spectrum of the light for

06:29

example this light here that shows its

06:31

LED light that's made out of red green

06:33

and blue LEDs to make the color white

06:35

and I can also take it and put in front

06:37

of the sodium vapor lights there is our

06:39

sodium vapor Spike at 589 nanm so let's

06:43

see if there's any sodium vapor light

06:45

hitting our subject mostly good but if I

06:47

look closely here I can see a tiny

06:48

little blip see that tiny little blip of

06:50

sodium vapor yeah science we're very

06:53

close but we're getting a little bit of

06:54

side spill on her and we're just

06:56

cleaning that up here if we're the first

06:57

ones to do this in like 30 years I want

06:59

to do it right you

07:01

know it went down nice that should be

07:04

better looks like we almost have a

07:05

perfect mat I guess the only thing left

07:07

to do is to shoot it maybe we should

07:08

shoot cool go ahead and roll the cameras

07:10

here we are in Mars the clown is looking

07:12

for the groom uh-oh there's aliens

07:14

behind you maybe turn around wave at the

07:18

aliens I want get one shot of myself as

07:20

well wearing my green hoodie which I

07:22

refused to take off and hopefully the

07:24

sodium vapor process lets us do

07:26

something Nico I want to see you do some

07:28

headbanging I want you to throw that

07:29

head

07:35

around I think we got it that would be

07:38

the hardest green screen shot that would

07:39

be so hard to do on a green screen and

07:41

cut dude this is going to be as

07:43

successful as Mary Poppins oh my god

07:45

[Music]

07:46

wow Paul's research has been super

07:48

influential on me to get to work with

07:50

him on an experiment is super super cool

07:53

I hope this works all right let's take a

07:54

look at what we got here's what our

07:56

color footage looks like and if I look

07:57

at the sodium vapor shot wow it looks

07:59

pretty good let's see what happens if I

08:01

take that and turn it into a black and

08:02

white transparency mask wow this should

08:05

work really well but before I try

08:07

pulling a transparency key here I need

08:09

to also try this with green screen to do

08:11

a true comparison to know if this is

08:12

better I'm using all the tricks for

08:14

perfect green screen that I've acquired

08:15

over the years lights with a hint of

08:16

green on them lights on Jordan with a

08:18

hint of magenta to cancel out the green

08:20

spill from the green screen I'm going to

08:22

do my best to light this green screen

08:23

and shoot it as good as I can all right

08:25

hi you're on Mars wave to us the

08:27

audience so we all know that sodium

08:29

Vapor should give scientifically better

08:31

results but green screen tools have had

08:33

years and years and years to mature I

08:35

can start pulling in the thickness of

08:36

that mat but while the dress starts to

08:38

come back the veil now has these ugly

08:40

lines I can try to you know close the

08:41

holes in the dress using a different

08:43

tool here but it patches up the holes in

08:44

the veil there's just no way to handle

08:46

the range of greens here and for green

08:48

screen tools to know what we want to

08:50

keep and what we don't want to

08:52

keep oh no yuck

08:56

destroyed actually not bad bad be honest

08:59

did you do your best with the key I did

09:01

the issue is is I can't get the

09:02

transparency of the veil and like the

09:04

slightly off green dress in fact the

09:06

only way you could do a shot like this

09:07

is to go in and cut out all these

09:09

different sections by hand and have a

09:10

bunch of Patchwork different solutions

09:12

in the image if the sodium vapor process

09:13

is superior it won't have any of these

09:16

issues all right so it's time to try the

09:17

sodium vapor process to do the composite

09:19

and see if it works here we have JC and

09:21

here we have our background right and

09:23

the way we're going to do this actually

09:24

mirrors the way they did it on film back

09:26

in the day the thing is if you just take

09:27

two pieces of film and you layer them

09:29

over each other you end up with a double

09:30

exposure you need something called a

09:32

hold out mat that leaves a hole for you

09:33

to Simply add your other image on top so

09:36

we're going to take our background and

09:37

we're going to subtract the mat we're

09:38

going to take our foreground and we're

09:39

going to subtract everything that isn't

09:41

the mat now I take our background and

09:43

our foreground and we simply add them

09:45

together honestly I'm really excited to

09:47

see this because it felt like we were

09:49

doing one of the coolest and most

09:51

high-tech things we've ever done and I

09:54

would love for this to pay off here are

09:56

the results and I'll let you guys be the

09:58

judge

10:01

[Music]

10:03

waa wow that's wild dude it's Mary

10:08

Poppins this is amazing it's

10:11

incredible oh no you dog water he's

10:15

drinking water on

10:17

M this is my favorite one the water is

10:20

just such a flex check out the motion

10:22

blur oh the hands oh wow the motion blur

10:26

drops the color exposure correctly on

10:28

the background right there turns it red

10:30

oh corrected ma oh my God it's so good

10:34

dude those little tiny hairs on top oh

10:36

my God and I didn't have to do any work

10:38

you didn't have to tweak your like white

10:39

clip black clip no I hate that D spill

10:42

bias no there's no spill what about your

10:44

Edge feather edge feather no D spill no

10:47

messing with gamma of your mat no

10:48

thresholds no restoring Fringe no

10:50

cleaning the blacks no cleaning the

10:51

whites nothing he's turn it on yes turn

10:54

it on wow good job good job that is

10:58

amazing

10:59

po y so I just got the opinion of

11:02

everybody at Corridor but I need to get

11:03

the opinion that actually really

11:10

matters oh wow you're zooming in on it

11:13

you are not afraid of your mat lines

11:15

that was clearly exactly what needed to

11:18

be filmed to show off this technique

11:19

exactly what about a volume could you

11:21

use a volume in today's age when you can

11:22

just go and shoot on a volume with an

11:24

LED screen is sodium vapor worth

11:26

pursuing in practice a lot of those in

11:28

camera back grounds will get replaced so

11:31

it seems like we're still in a world

11:32

where we need to be able to cut out

11:33

backgrounds and put people on new things

11:34

yeah flexibility in post- production is

11:36

incredibly valuable one thing that

11:38

you're noticing is like composing tools

11:40

are getting better CU they're starting

11:41

to have a bit of machine learning inside

11:43

of them machine learning needs training

11:45

data the question is where do you get

11:46

all that training data there is no

11:48

perfect easy compositing technique and I

11:50

thought this would be a good way to do

11:51

it so sodium vapor is another one of

11:53

those essential steps in this progress

11:55

towards having perfect transparency for

11:58

compositing and visual effects then

11:59

absolutely it is the gold standard the

12:02

yellow

12:03

standard well Paul thank you once again

12:05

for joining us here on the corridor

12:07

Channel if you like these deep dives

12:09

into classic visual effects technology

12:12

along with industry experts talking

12:13

about it you'll definitely love our

12:14

Abyss video so go check that out and uh

12:18

yeah thank you I really appreciate it

12:19

great to see you glad you come mind this

12:21

was fun this is a great time

12:23

totally