All language subtitles for Nuke 102- CLASS 3- Advanced Keyer- Top Dog Industry Keyers

alright so this is a class 3 nuke file

and we're gonna talk a little bit about Kiers

now this is an advanced tutorial

but I wanna make it available to even beginners

in the sense that I wanna introduce

you to a little bit of the most famous Kias

uh the big top 3 obviously are primat

and of course there's the other one key light

and finally there's the Dynamic Duo

IBK Gizmo IBK Color

so these are the biggies right here uh

some people um

do prefer sometimes to use ultimate

which is another one

which actually can

basically take out any webbing

that would be involved in

certain areas around a character

if you're trying to create a format and so forth

so it does give you some really cool results

a little bit more complicated

but the big ones are primat

key light and these two

these two are usually good for fringe mats

or commonly called edge mats as well

and primats are usually good for core mats

or kind of hard

cores that we're going to create

which is the center piece that fills in

the Swiss cheese holes of your atypical key

so let's go ahead and just kind of poke around with a

couple of these here

let's go ahead

start with key light alright

so I'm gonna go ahead and take this footage of Jessica

and we're gonna go ahead and plug it in

as you can see

you have a background outmat

inmat source

I am not gonna get in heavy detail to any of these um

because I want you guys to go straight to production

when I start in production and game design

uh I didn't have like theory

or ideas or you know

maybe you could try this with this

you know maybe this will work

in production

you literally are thrown into the lion's den

and you got to fight off the lion

and that's just basically the process of production

and we were given templates

and you know

best course of actions that you could say

are very linear with not many options

but for the majority of the sake they work

so I will be introducing you to the Uber here

which will be a templated Kia

which will have all of these sort of pieces

but just to be aware how the mechanics of these work

I'll just go ahead and put in source here

to our footage

and there's plenty of tutorials on YouTube

um in regards to um

learning about this

I'll talk about them a little bit later

but I'm just gonna go ahead

and put this into the viewer

and here you can see

we have our scene here

and you can see

if I go ahead and slam the gamma

we have a variation of luminance in the green

so you can see we have a variation in

say you know

the actual luminance

it's brighter over here

it's a different value

so if I were to click control click

you'd see the value of red

green and blue

are different than here

this is like point seven two

in the green

it's point five here

it's point o four in the red

over here it's point o two in the red over here

and over here

it's like point

o six and over here is like point o four in the blue

so there is a variance in color information

between these two areas

so key light is good for scenes where

there's a lockdown camera and

you don't have the camera moving a lot

where the background plate would actually change

so if you have a lockdown tripod shot

where the person's just walking along

and the camera doesn't pan or tilt or dolly

uh this is probably the best tool to use sometimes

for hair detail

um but again

you can get this done as well

with certain situations with IBK

uh coloring gizmo

which is the

most popular of all the cure

so I'm gonna take the key light

and click the little screen color here

and I'm gonna go ahead and hold down shifting control

and you can see

how it starts to do the disco here

where it goes back and forth

and I wanna hold down control

alt and click

if I hold down

shift control and Alt

this is on a PC

I'm sampling the original image if I

don't hold down that

I'm going to get this

and sampling the sample

so I don't wanna do that

I wanna make sure it's sampling the original footage

and ignoring what has been changed

so I went ahead and sampled this area

and usually

you wanna sample areas very close to the wispy hairs

and now if I hit a for alpha

you can see we have a pretty good reality here

you can see

the difference in luminance

it's all based on the pixel

value that we chose here

so whatever

the crominance value

RGB of what we chose here

is what it's keying

and you can see it just degrades over here

now if we choose this area over here

you can see it does

a really good job

but we might be losing some details

remember you can win the battle

but lose the war when it comes to keen

um you wanna have that yucky

mucky motion blur

and you wanna have these fine

wispy details

so you can see

just by poking around again

I have hit a

for alphata

look at my alpha

I can kind of

choose something

that's a good middle ground

but one thing you notice

if I go over here and go

all that looks good

you'll notice I've lost detail in

the hair over here

so if I click over here

you can see I've gained

and this extra

strand of here

so this is gonna require

a little bit of finessing

so I'm gonna

get kind of close here

and you can

see I've got

all these nice hair details

and at this point

we can go ahead

and just do a

couple things

such as screen gain

which is gonna

kind of pump that up just a little bit

you can see

it's starting to

eat away at the hair

which we don't want

we don't wanna tamper a lot with keys

I know it sounds kind of

weird but we

don't wanna

get too crazy

and then the screen matte

we're gonna go ahead

and click that open

and we can click

click the black

and we can clip the white

and you can

see it just becomes a crunchy nasty edge

so as these

two come closer to

each other is

black gets closer to white

these two bars

two little knobs get closer

you're crushing the values

you're basically saying

anything of a value of

2.95 in the

RGB or higher is being

turned to pure black

and with the white

anything lower than 5.95 is going to be turned into

white and it just crushes

the value you lose

you win the battle

but you lose the war

and you don't have

all those fine details

I'm gonna be

very careful with this

and maybe take

the clip black

and just inch it up just

ever so slightly

now there are other tools in here

which are used

here and there

like screen softness

you can see

it just softens

the edge a little

bit overboard

you can soften that up

if you want

if you're getting sort of stairstep edges

um and there's

you know d spot

black which just kind of

kind of does an erosion

you can see

you're getting these

very strange shapes

here uh again

heavy tampering is

is something that

you don't really wanna do too much

in this case

we're just dealing with

uh actually

getting the

cut out mat

I'm not worried about destroying

the image here

so with that said

we have this piece

of key light

that looks good

this this portion here

actually looks

very good now

what you would usually do with this

is do a region

per region basis when

you're dealing with

key light and again

it's good because it's on a lockdown camera

so I'm gonna

take this key

light paste it

put in my source

and I'm gonna

go ahead and

come in here

hold down shift

control and alt

resample my

actual color

and I'll go up here

by the hair up here

right so this is

I'll go ahead

and label this

call this top head

I'll take this key light

going to my node and label this

you know right side

which would be camera right where we're facing

and I'm gonna go ahead and paste another

one of these babies

come in here

and again choose my color

and again we get close

to the edge here and see if we choose

see it's very gonna be very careful here

there we go so this would be more of the top left

so go ahead and call that top left

here we go and last but not least

maybe we should hit up this corner at the bottom

so I'm gonna go ahead over here

but the viewer in here again change the information

I'm gonna choose and get this area here

look at all the detail coming back

the man I kind of punch around so this would be the

bottom

left okay so

let's start to combo these with a key mix or

so here is a key mix

and what we're gonna do with this is

I'm gonna go ahead and put this to B

and a is what we're going to keep or in the mask

so a is what's going to be revealed in the mask

I'm gonna go ahead and hit the letter

ode and make a rhodonode

and this is the top of the head right

so I'm gonna go ahead

take this roto node

and let's go ahead oh

you know what

I had the gamma on while I was doing all those checks

let me go and double check my results here okay

so that's the top head

that's the right

let's go ahead and

maybe refine that a little bit

another thing we haven't done is actually denoise

our plate which probably be a good idea

but I'm not gonna do that

just for the sake of this demonstration

and so we have this right side

and then we got this top of the head right

so it looks like this area

so I'm gonna go ahead

and do my best to grab this area here

I'm gonna go ahead and hit the letter B

and add a slight blur to this roto

there always should be a blur on all your rotos

so a is basically being added to B

so anywhere else is the B input

anywhere in this roto will be whatever is an A

so if we put those together

you can kind of see the difference here at this case

I can go ahead and come in and here and

maybe extend this out here

right there

so you can see the blur

we don't have a blur there

the transition can be harsh

so if I go ahead and put this blur down and nothing

you can see you got that harsh edge there right

so I'm doing this kind of quickly by the way

just so you're aware um

so on top of that your daisy chain here

so you take the input of B

and now we're gonna add in this here a

and we just do one last adjustment here to this roto

but it's region per region basis right

so go ahead and get let's go

out that far

there we go what the heck

we'll crush some of these values over later

if we need to alright

so then again here once again

we'll take this key light will add another roto mask

so hit oh copy and paste this blur

plug that in

plug this in

and this is of course the top left

so that's this little segment right here

so go ahead and throw that in

there we go

and it looks like this

key could probably use a little bit work

I'm gonna put my viewer to it

and just come in here

and kind of get the best result I can

but still maintain those hair follicles

gonna be a little bit tricky

see the closer I get

yeah we're gonna lose some of this data regardless

okay so that being added on you can see there

I'll go ahead and just extend this out

and again I'm just

this is probably not as optimized as you would imagine

okay and then we have the bottom left right

which is this area

so again I'm gonna take another key mix

paste it B input a input

o for roto B for blur or just copy and paste this blur

plug it in mask it

and this roto I'm gonna throw down to this area here

there we go

so it looks like it only got a hold of this area

right here and I can keep going with this right

so I can say okay

um this area right here

I'm probably have to do a separate key for I'm just

being very careful to do very light keys on all this

I'll just make another one and this will be middle left

so do middle left

and we'll put that in

and we're keying based on a luminance change

crominance change for each individual area

so I'm gonna just hit this keyer

hit shift control and alt

click the little problem child area that I wanna get

get as close as I

can before it starts to get goofy on me

making sure I keep as much hair detail as I can

again copy paste

and you probably wouldn't use this many

you know key lights

sometimes you would obviously

and this is where IBK Gizmo actually

does a lot of this stuff for you

an autopilot

so I'm gonna go ahead and copy this here

plug it in and let's go ahead and take a look at our

last viewer

look at here

and then I'll just add in this area right here

so I'm just kind of adding in

little areas here as you can see and again

I'll just kind of bring this to the best I can out

obviously this will have to be animated

if it needs to be animated

obviously because the cameras not moving

you probably could leave these static

but if the camera had to pan or something

you'd have to animate it

so in general

I could come in here and create a merge node

and we'll go ahead and create a mask

so again I'm gonna hit 0 for roto

and I'm just gonna come in here

and mask around

make a garbage mask around our character

as best we can

and we're gonna have better

robust ways of doing this later by the way

and again I'll just copy paste this blur

B input a and we are going to set this to mask

so there we go

we got rid of all the gunk on the outside

at this point

we can hit the grade node

and come in here and maybe crush the

values a little bit here

we can come over here and play with say

play with the multiply again

you wanna set this to alpha by the way

so make sure this grade node is set to alpha

and I can just come in here and just start playing

my viewer to it

playing with certain options here

you can see I can play with the gamma

which will kind of eat into my um

thing here a little bit

I could also come over here to my blacks

start to crush the values just a hair

and then of course you got

you can try multiply

it's not actually it's not gonna do any good

unless you have a weight clamp

so again just a little bit of detail

you can see if I do a little too much

I'm gonna start through all these fine here to details

but sometimes there is a compromise in that

so now that we have an actual alpha here

I'm gonna go ahead and use a copy note like this

and we're gonna go ahead

and bring in the actual footage itself

so I'm gonna go ahead and take this

and put this as the incoming RGB information

and then the a is going to be the actual oops

I'm sorry yeah

that's right

a is the alpha information and B is the RGB information

and we're basically reformatting what is

RGB and what is a

so if I go ahead

and plug this through to the original image like that

and we can go ahead and hold down control

make a couple downloads

to kind of come around to the opposite side here

here we go

so now you can see if I take a look

here's the original footage hit a

here's my alpha

and I could pre molt this

so type in make a pre molt

so I multiply the alpha by the actual um RGB

so it cuts it out

and there you go

now just by looking at this

you can kind of go and say wow um

this could use some you know

coming to grading here and crush the uh

you know this area

but we have

so much of this green here in the actual object

and if we were to say put this um on a background

if I were to go to my constant here

and let's choose a color here

let's choose something like I don't know

something brownish like that

and if I would emerge this B for background a for a top

you would see

that we got a green Halo around the character

now the key light

is actually good on its own as a

what's called a d spiller

and usually within keys we have

the area that we key out

and we're not worried about the red

green blue information

and then we have the area over here

which would be

dealing with d spill

which is getting rid of the green out of the

reflections because a green screen behind this actress

is not only gonna cast green on her face

around the edges of her

um around her hair

um it's just gonna pollute it because it's light

it works again

it bounces around like photons and just you know

white areas absorb or

white areas reflect and black areas

absorb so you're not gonna see a lot of

green in her black shirt

but you will see it probably in

her face a little bit so

key light on itself actually works as a good d spiller

so I'm gonna come over here

plug in my source

and I'm gonna set my screen color on this

1 to 1 for green and voila

we have taken out

the green spill now

usually I come in here with the alpha bias of the red

cause her face is red

and I'll bring this up to 6

okay you see

as I do that

there's less

there's more green being taken out her face

and also her hair

see the difference

see that just by bringing this up one

you put this to maybe point five

five if you want

you don't want her turning into a

um a strawberry or a blueberry

which happens is you

kind of fiddle with this stuff a little too much

you can see she's starting to turn into a blueberry

if I go too nuts

so having a alpha bias 1.6

I find is a good kind of balance again

if you need to push it

you still see there maybe some green tinge in her skin

and that's something

get through

using maybe a hue correct

but we're gonna get in that later lesson

so this would be the redefined RGB

okay so we're gonna go ahead and plug that in

notice that the background information here

is unbelievably

uh actually um

ridiculously dark right

so we've lost the luminance because we basically

taken the green channel out

so one of the things we can do with that

is actually come in here and use a merge node

and we're gonna extract

uh by clicking here for a

B right here

and we're gonna extract

you know minus operation

so hit minus

the green information

this is the green

information that we tore out of the scene okay

so you can see there's a lot of it in

around her face here

in her teeth

cause her teeth are reflective

and along here

and here you can see the shirt isn't

doing that because black absorbs

a lot of the

light coming and bouncing around

so with that

now I can go ahead and hit m for merge

I'm gonna hit sat

for saturation

I'm gonna come over here

take the saturation ring that done to nothing

so now it's just black and white information

but it is lumens information that we lost

and we're gonna re

introduce that

by putting a merge note from B to a

we're gonna set this merge note to plus

now we have re added

the missing

luminance information

but yet she is not green

so there is our final

commonly called the d

spill or the red green

blue information

and this is our alpha information

we merge that together with a copy node

and now when we merge this together

we have a nice

looking background now

um I don't wanna jump any further than this

because I obviously wanna

get into the other tools such as the gizmo

um and the prime at

but a quick fix

for the fact that this hair is gray

cause the luminance values are different um

and also the color is different

is you can kind of cheat this by going back to say

your key light

and adjusting

the red color influence

so usually I put this to point zero one

on the d spill

and as I start to increase this

go back to the actual image here

and just see what we're doing

you can see

as I do this

I start to reintroduce a little red

so that it's actually changing to match her hair color

see that I'll go to the plus sign

just so I can see

you know everything together here

but you can see the difference here

you can see that

now again I can really push this if I want to

by dragging this pretty high

and this might start to change her skin tone

but this background image is matching to her hair

as you can see

so again there's a lot of things you can do

you can also come in here and bring down the

intensity of the mix here

but I just wanna show you

by making some slate alterations

of the color information

and go over here to the merge node

now it's matching up a lot better

as you can see

we still have

you know color differentiation here between what is

the back plate and what is not

because the information of the gradient of the alpha

is still showing the back plate

what's behind her which is

all determined by how we actually did our d spill

so you can see we've matched her up pretty good

and if I just go ahead and scrub through

obviously in this circumstance

you always want to put your viewer to the last

merge node and put your second viewer to the

your original plate

you always do this

you always always go back to your original plate you

you wanna go back and forth

look to see what you lost

and you can see we lost a ton of information here

so you can see here

we've got all of this information here that's been lost

oh my goodness

how do we get that back

well again it depends on the key that you're using um

one last trick I Learned from my good friend

uh working in the studio was

where you actually color correct the background plate

okay so this right here

let's go and take a look at our background plate

here it is right

it's just this stupid constant right

what you can do is actually put a grade note in on this

and what you can do with this is

we'll go ahead and take a look at her hair real quick

I'm gonna hit R

G and B and we can see the green channel

is where we get the highest amount of contrast right

so I'm gonna do an old type of Kia

which is called just a regular Kia

so these are used a lot in kind of pulling out

um luminance base keys

as well as ground shadows so I'm

gonna go ahead and put that into the original plate

and I'm what it does is if I put this from

uh you know

we're not gonna deal with luminance here

but I'm gonna go ahead and put this to

uh based on green here right

it basically takes the green channel okay

and floods it in to the alpha

so if I go and take a look

I hit a for alpha

you can see what we have here

so I'm gonna go ahead and crush the values a little bit

in here and this is basically a gradient

of the values from 0 to one

here we go now

we also gotta invert this

I'm gonna invert it

and let's see if we can

play with this other bar

you pull out this other bar here

and it's kind of clipping that

you can see it's gonna be very hard to extract this

all these fine wispies

but we're gonna grab whatever we can

and the white is the area that's gonna color correct

so I'm gonna go ahead and make a dot node here

so we can extend this

bring this down here

and bring this baby all the way down here

there we go

and I'm gonna go ahead and plug this in

before I do that I'm gonna go ahead and add a mask

so I'm gonna merge this

cause I don't wanna color correct everything

so this will be the incoming image and then

the a will be a mask or roto that I will create

and that roto will be only around the hair areas

and this case I can only isolate this area for now

I'll have to do individual keys that are

just like we did with key light

based on the luminance of these different areas

but I'm just gonna use this area for an example

I'm also gonna grab one of my old blurs here and

paste that in

there we go

that way we just have and I'll put this to mask

so now you can see we just have this area cut out

and I will use this as the mask for the grade

for the background

so now you can see if I take a look

and I'll take the grade

and start to multiply this down

look at all the hair detail

it has come back in that little area there

so now I'm gonna go back to my merges

my original

and my end of the

end of the line

front of the line

and you can see we've retained all this information

based on a hack where we've color graded the background

now we've color graded it

unfortunately

in a color that is black

so you can come into this

multiply here

click on the 4

and play with

if you wanna make it more like the color over here

which might be a little bit more red

so you can kind of

play with that a little bit

so you can go ahead and see the difference

between that

you can see a huge world difference that this can do

to retain values that you couldn't get out of your key

due to quite the variation of a green behind

the actress

so a lot a lot of stuff I'm thrown at you okay

so the next thing I wanna show you is the prime at

so the prime at

let's go and drag this baby over here

and it will bring our actress here

primats are usually used for creating cores

um which is very important to understand that

despite all of this keying that we did

if I go ahead and take a look at her actress here

you can see if I pulled it down

she is you know

slamming the gamma

she is still transparent here

so if I were to sample this area here

you can see the

the actual value is point nine

nine eight okay

so that is technically unacceptable in regards to um

an alpha input that you can play with here

it's it's 1.05% or lower is what is

allowed in regards to transparency

um for the most part

especially out here in this area here

kind of sample here

you can see the value is like point zero three three

that's that's fine

even though we do see noise here

it kind of translates itself into

not being seen in the plate itself

but if you get values in here on the black area

that are above point zero five

then you got a problem

so it's sort of like the middle ground

even though you see gunk up here

like let's sample this

so the average is point zero two right

so that is actually acceptable

that will not probably be seen in the final output

and we can test it just by looking at it right

if you see sort of noise up there in your shot

then you know you gotta deal with it

but in general

it's it is what it is

so it's again

let's go back to our prime at

primats are just very destructive

in the sense that it's almost like

creating key with a permanent marker

if you make one mistake

it's hard to go back

and I just find that the undo button is a bit buggy

so I'm gonna go over here

plug in the foreground

and take a look at it

now this is what I call three dimensional Kia

what does that mean well

if I come over here to this nice little color wheel

I've put in the scene for you

put my viewer to the roto here

and double click my roto node

you'll see it

the key light was using a variation of luminance

and crominance

to pick out an area

but the great thing about a primat

it's a 3 dimensional key

it almost like works

like a wormhole

um if you wanna talk physics

where it can jump to different areas

that are not connected

usually as you increase the area that you want a key

it kind of grabs everything in the middle

as you extend it out

but here's a way where I can actually grab

and again this is the gradients of

the tolerance of what it actually picks up

um actually gram stuff that's

outside of that sort of diamond

so to speak

so it's really cool

it's a three dimensional Kia

so let's go to the prime at here

I'll just double click it

and again you have this option

your operation

this stuff is very

dummy proven

go here to smart

select background color

and just like we did with the key light

you're gonna come over here and click a color and boom

we've got a starting point

so let's go ahead and hit a for alpha

and sample near there

and now all I do is go to clean background

and clean foreground

so I just go to clean background noise

anything that should be transparent

I'm just going to hold down shifting control

and gobble it up

as I do this

and you can do it by grabbing a whole area

but actually make you

it's starting to make your edge a lot crunchier

so I find that just

clicking once in a while

instead of clicking and dragging like this

uh can kind of save your key

so with that

I'll go back to my clean foreground noise

and bring down my

slam my gamma here

and I can come in here and grab

the center area is like crazy

now you can see what's going on here

it's starting to harden up my mat really badly

okay and that's just the

the reality

of this whole thing

click on viewer here

and you can

see the actual three dimensional representation

of what is being keyed out in this in the red

green and blue channels here

in the three dimensionals space

if you wish

just it's nice eye candy

but it really doesn't help you very much

so now you can see

everything looks relatively

you know blaze

um you know

if you were to merge this on a background

the edges would be a little bit harsh

so if you were to compare

the edges of what we create with the prime at

versus what we have in regards to uh

we do with the key light

you can see the amount of detail that's been lost

the good thing about the key light

or the prime at

I should say

is it works as a great tool

for actually creating cores

because it still maintains the edges

but allows for a hardened center

so you usually would come in here and again

clean this up a little bit more

you probably grade it a little bit

so you can come in here

and grade this oops

do another green

but a grade

and again you'd set this to the alpha channel

and you come in here and crush the blacks a little bit

so you can see as I crush

the black starts eating into the mat

crush the whites

ever so slightly

and now you have

you can slay on the game

you see we have a pretty solid

center there

but this actually has access as a core

that if we were to hit m for merge

we could actually after this

merge this on top

so I'm gonna merge that on top of um

the footage here

so I'll just bring this over here really quick

so here is our

you know key light

which has holes in it

and if I take a comparison between the two

you can see this is a little bit skinnier

now this could be troublesome because these areas

you know obviously

these areas of the semi transparent areas

and this is fine

um in general

you might also wanna come in here

and play with the gamma

as you can see it kind of eats in a little bit more too

um you can do that

you could also use a lookup tool

which I'm gonna go over later this

and I'll go ahead and set this to

let's put it as well

let's just plus it now

I wanna show you what happens when you plus something

you get values that are above value of 1

so I'm gonna go ahead and

put in a quick clamp node here

like this and now those values are no longer that

they're limited between the normalized values of 0 to 1

or you can go ahead

put this to say screen

just usually a nicer way of working

and you can see the values are still normalized

so screen is actually preferred

but you see what it did

is it filled in these areas here

so now if we kind of look at her again

you can see we have a nice core

so it fills in the center

so that's why primat is a really good tool to use

um through this whole process

and I'm just gonna organize this just a tad so

you guys can

have it look you know

take a look at this

I do have the start and finish for all these files

so you're not like

what did you do

you know I could just go ahead and show you

so let's go and take a look at the final result

and there she is looking all joyful

we still have some green in her face

and these are the subtleties

you gotta keep an eye out for

as you can see here

and we'll get into

how we're gonna be dealing with that a little bit later

but as of right now

that's just a quick example

now the final cure

I'm gonna go ahead

and show you guys

is the IBK Gizmo IBK color

this is the most popular in the whole process of uh

keying and so forth

so sometimes it's hard to explain

what in the world this does

so here is our actress

I'm gonna go ahead and add a d noise while I'm here

so let's go ahead and add a d noise

put the d noise in the source in

sample of my area

and now we have taken out the noise in the shot

so go and take a look at before

and after their noise is gone

we blur the image a little bit

which we can sharpener later on

um which if you sharpen too much

you'll get black edges around heavy contrast areas

and it's not good so again

anytime you tamper with the image

you're tampering in God's domain

and you're fiddling around

and it can degrade the image and make it more synthetic

so we have the IBK color and the IBK gizmo

so what does this do

well I'm gonna show you using a roto paint node

what the heck this does

so what it does is it takes the original plate

and it take it

this is gonna sound really goofy

when I kind of describe it

I'm gonna take a smear brush here right

and what it does is it basically does this

it's basically taking the sample color

you know how we had different luminance values

all around her

head because it's darker over here

as it is lighter over here

basically what's doing is it's just doing this

it's choosing an edge and then eroding it

in from that edge

as you can see here

so imagine go ahead

make this crazy big

it's doing this

so it's moving the sample color here

which is most likely the color that should be sampled

and it moves it in to the characters center

and what we're basically doing is a process as if

we got rid of her completely okay

so I keep doing this till the sun goes down here right

so if you were to take a look

the difference

it was almost as if

it's a fake backplate

or I should say clean plate

and clean plate

usually if you have a shot

if you're on the stage and you're VFX supervising

and the shot is a lock off shot

meaning it's a tripod shot

lock down tell your

DP to shoot some footage with the actor out of the way

and that footage can be used as a clean plate

um but this creates the artificial clean plate

which is if we told the actress

get the heck out of the way

and we shot some footage

so you can see it looks as if she disappeared

I could keep doing this till she disappears

as if she actually is um

out of the shot is all it's doing is smearing in

the the pixel

values around here

and then it's using a difference keyer

the difference between the back plate

and the original

and taking the character out

so when I like to call it a difference keyer

okay so with that said

let's go ahead and create that so

we don't use obviously

a smear brush

we use the IBK color

which we're gonna plug into our d noise

this thing by default is always set to blue

I don't know why they just set it to green

because most people use a green and secondary blue

but it's set to green

and I think that's because

the old software used to use blue screen more than

used green screen

switching over from film to digital or whatever

um so you can see

the image you get is this very

very odd image here

where she is

um basically

it has an outline

hit a for alpha

it's actually choosing an alpha so this is

the best that it can do is basically keying out

you know basic green here

and what you have to decide here is the size

as you can see here

by default 10 is usually fine

and then you have darks and lights

so this is basically in the same way we were doing

keying with key light

um defining out the tolerance of uh

brightness versus contrast

I'm gonna put this to point zero one

and I'm gonna start dialing up this one

until it kind of

chews up everything

we wanna get

even those hair wisps

if we can now

if you do this

it starts to explode off to the side of the screen here

as you can see

it's like oh crap

that's not good

so I wanna kinda wait till it explodes and stop

and I'm gonna go to the lights and put a value in there

on the greens

and I'm just gonna start fiddling with this until

I can get something

there we go

now the next step is in a row that just

basically a row just

erodes in or dilates out

the actual alpha edge

so now I'm trying to get

trying to get

all these hair details as best as I possibly can okay

so go ahead and

fill with this a little bit

you see if I pull it

I can over crank it 6 7 8

scenes with heavy hair

lots of hair

and not hard edges

are a little bit tricky

you might have to introduce a mask

which I'll talk about

I'm gonna demo later on

where you actually introduce

more to the roto by

adding in more alpha

via Roto note

but the hairs are tricky

I would actually come in here

and roto this area in and

add it to the Alpha mask

cause it's no good

so you can see what it's gonna do

it's gonna take the pixels on this

where this line is at

smear them in

so you can see the patch black is gonna do that

so I'm gonna go ahead and drag that in

and I can over crank this to ridiculous

now I'm gonna talk about the daisy chain

version of this later on

but I basically brought this to a patch 20

so let's take a look at the original image

let's take a look at the shot

it's almost like we told the actress

get your butt

off the stage

and there we go

now we're gonna have

problems over here with this hair okay

cause it's gonna

use the difference between this and this

and do the key okay

so here's the IBK gizmo

I'm gonna plug in my clean plate

which is this

or if on set

I told the cameraman

get the actors

out of the way and film

and he gave me some B roll footage

shot temporarily in a different time

I plug this in here

because it was a lock off shot

and now I'm gonna go ahead

and put this in my foreground

and take a look

I hit a for Alpha

now again by default

the IBK gizmo is set to blue screen

you have to set this to green screen annoying

but look at this

this is like everything we did here

right but done

all at once

with this node

because instead of

instead of sampling

this area this area

this area this area

this area this area

this is basically

using a difference mat

to get all the details for us

all at once

let's take a look

at the difference

of what we created here

versus here

you can see

the difference

look at how much detail

is in the IBK

I've talked to many of my

students that are

big time VFX

guys now and

you know they are

there are still

this is the best cure

so it saves time

and why is this good

well I did a

commercial with

Sam Jackson

the Capital

one commercials

I used to do

and you guys

can look them up if

you want Chasm

Snow Globe also

tiles they're

all on YouTube

and so forth but

Sam Jackson is

moving through a scene

and he is basically

he's moving through a green screen stage

and the luminous is changing behind the

actor so this

wouldn't you know

a moving shot is not good

for key light

whereas a moving shot

is great for

the ever changing

background of

the character

in say using

the IBK gizmo

so with that said

you can see

obviously we have some noise patterns here

if I sample it

the values are

at point zero

zero four right

those are acceptable values

actually not

even though we can

see the noise

um those are still

acceptable values to be used

and overlaid

even though you

people usually will come in here

and you know

they'll add a grade node

they'll set this to alpha

and then they'll start

coming in here

and crushing

the blacks until

you know lose

all the detail

but look at all

the hair detail

you're losing with that

see that we've

won the battle

but we've lost

the war so again

I'm going to maybe do a

just a little

bit of clean up

and even bring in

the white point

not as far as like point

like nine 90

cause we still have holes

in our character

as you can see

this doesn't fill in

the holes in

the character too much

on this case

actually it does

does pretty good again

I might bring this

I don't wanna bring this too crazy

maybe point nine

seven or something

did a pretty amazing job as you can see

now we would probably come in here and do another um

let's create a merge node

and we're gonna create a

oh for Roto

and let's just make a quick garbage mask while we're

here so just go through like that on

steal one of those blurs over here

paste that baby on and set this to mask

there we go

and again just blow this edge if I want

there we go so pretty cool and again

it gives a beautiful absolutely beautiful result

from which if we were to swamp this out right

so go ahead and swamp out the a here for this input

really quick

so basically doing all the work that Key Light did

except this time we're gonna see the result using uh

the actual uh

IBK coloring gizmo

and look at that

all those here details are there

now hair can be

a bit of a pain in the rear end with the IBK gizmo

because you really

to collect the hair can be tricky

so I usually introduce

some manually animated rotos to cover up

all the hair when it comes to this area right here

so even though

you know this

this is the quick way of doing it

I'm gonna show you the daisy chain version

which works even more effectively

than the whole process

so that in a nutshell is all the keys again

you wanna denoise it

you can also use this screen clean tool

um but again

um you gotta

don't get too crazy

cause you'll start to lose details and the highlights

or as far as the motion blurs

and the actual wispy hairs

but you can see how just these tools alone

and now this is still not gonna cut it

we're gonna get into crazier

even more powerful cures and d spills to really make

everyone kind of blend in

we gotta talk about graining

regraining image

I'm taking you guys all the way to the professional end

so that if you were to show up at say

the mill or

any one of these studios

you would be ready to do keying at the very least

that's just one element of composing obviously