All language subtitles for Nuke 102- CLASS 2- Advanced Keyer- Plate Clean Up Work

okay so in this lesson

we're gonna talk about image preparation

and understanding

you know that an image comes in

from the real world

with imperfections and all that fun stuff

we're not talking about tracking or anything like that

in regards to lens distortion

but there are certain

elements that we have to deal with

digital or film

you're gonna get film grains

if I go ahead and kind of zoom in here

you can see there's a noise pattern here

throughout the image here

and that noise pattern is not very

prevalent in the green channel

but you can see if I go to

there's a red channel

you can see the difference

green channels

pretty clean

if I hit B for blue

you could see that it's just pretty noisy right

so the big thing when you're talking about

taking something and keying it

or taking out the green here and putting a background

is to definitely consider a d grain

so there are a couple of options for this

one of course

is the relatively

okay degrain simple here

there are other degrainers that you can find

say through newkipedia and so forth

but the one that they do

use in the industry is a neat video

it's pretty much across the entire industry

that neat video

a 300 dollar plug in for nuke

is the industry standard in regards to degraining

for the sole reason that

the algorithm actually creates a

retains the sharpness of image

whenever you grain something actually blur it

neat video is computationally expensive

but in the midst of all of that

you get a sharp image here

which doesn't require any sort of

resharpening at the end

down the pipeline

um you'll eventually probably have to sharpen a little

bit up as you start to lose

the actual degrading of image through resampling

all the way through the process

but in general

this is $300 that if you are very heavy and intensely

using green screen stuff for your projects and so forth

it is the best investment

of all the plugins that you would purchase for nuke

this is the one to do it

now in our case

I'm just gonna go ahead and use the d grain simple

and we'll just show you the

kind of artifacts that that introduces

so I'm gonna go ahead

and take this shot with Sterling here

and go ahead and plug that in

and I'll go ahead and just show you

so you have the d grain simple

and you can see that it just basically does

an okay job um

you can see right here

that it's basically using the red

green and blue channels in the amounts for each

so you go to R or you can see that we have a

a green here amount

and if I just start to pull this up

we start to finally clean that image up

if I go to the green channel

now you could see

and I don't have to get too harsh with

the green channel because it's pretty clean already

so bring it just probably down

now go to B for blue

and you could start to crank that up to some ridiculous

now what does this do to your image

well let's take a look at Sterling here

as we kind of

hit d to disable this off and on

so I put my viewer to it

you can see Sterling is blurred up pretty heavily here

through the process

not too bad

cause he is a little bit out of focus already

but in general

we've gotten rid of the green to a certain degree

you know still some color noise there

skittles color noise like to call it

but in general

I mean it is what it is

you can use the d grain simple

um if you prefer

there's also the plug in for the d noise

so the d noise

go ahead and click

that is another option here

so we can go ahead and throw that in

and it's gonna ask for a sample here

it's gonna give you an error message up here

so I'm gonna take the noise

and plug that into this image here okay

I'm gonna go ahead and click on the d noise

and again you're still getting an

error message because it says that the clip

sampling area is too small

so I'm gonna go ahead and grab this

find a uniform area here

and allow the

to scan that and do a um

d noise so you can see

but take a look at this

go and put my viewer to it

here's the old

here's the new

so I can bring this down

so you can see this a little bit

I know you guys are watching this with a

YouTube compression

but there is a

a lot of noise taken out

which is essential for when you're doing keying

and this is only on the side of the actual mat side

not the actual d spill RGB side

but just the alpha that we're gonna be pulling

and you can see

if I go ahead and take a look really closely

we have had

a degradation of image

in the sense that it's very

very blurry

now um this is

somewhat computation expensive

usually you wanna write this out to a DPX sequence uh

just go ahead and write it out

you know you know just

dot you know

you can use whatever

token you want

but I usually do three hashtags DPX

and export this out

because you can see as I kind of scrub through it

in this case

I have a pretty fast computer um

but in generally

it can be competition expensive

so usually you

export this out

and then to make a right note

a read note

you just come over here

um under the right note here

and you just click on read file

so that makes it an actual

readable file

so it's basically turning the right note into a renode

so let's talk about cleanup

and when I talk about cleanup okay

we talk about denois

so we've denoised the plate here

so I'll just go ahead and give her this right note

and you can come in here and do a lot of things

for instance

you can do a roto paint to take

out these tracking marks

because Stirling actually crosses over

I use my arrow keys

there's parts in here where he does cross over here

so you can see

in this example here

you know we're getting the tracking down

we're getting this motion blur

so some people would come in here on a perframe basis

put a roto paint note in

and just come to the clone tool

and let's go ahead and just try to clone this out

the best we can

so I'll go ahead and again

I'm using a single frame here

and this will be a little bit tricky to pull off

so see if I can pull it up with my viewer to it

and you can already see how it's

it is what it is it's not

it's not the best

reality here

um and again

I wanna show you a little technique to deal with this

you can see how

crazy this can get in the process

now someone's gonna fly by

um the shot

and if you don't notice it

you'll be okay

but you got to be careful

very careful on this sort of stuff

when you're kind of cloning it out

cause obviously we got a little bit of blur here

um on Stirling

kind of coming through here

so there's a whole bunch of

ways of kind of cleaning this up um

one of the things you can do with

your Cologne tool is set the opacity down pretty low

and set the hardness down really low as well

so I can put the hardness to 0

and I can put the opacity to say

like point you know

one or something like that

and then I could just start to

kind of blend this in as best I can

and it's got to be consistent

so if I go ahead and d and disable

you can see it's okay I mean

would somebody notice if it flew by

for instance

I just go ahead and take a look

like here we got this

and then we go here

as long as there's no crawling around along the edges

and one frames

you know if there's more than one frame

then you got an issue there

so you got to be very careful with that kind of stuff

so anytime when Sterling actually crosses over

um here is gonna be

an issue to take care of

so same same thing again

I'm gonna have to kinda

grab from here and you

can do this after your key as well

I'm gonna show you guys the process of doing that

which I Learned from a

good friend of mine

Brad who uh

is since then working on

major motion pictures um

in the industry so he's a

he taught me a ton and I'm

very grateful for him

so a lot of

the techniques I'm gonna be teaching is this course

we're actually taught by uh

people that are in the industry that are

big shots that flew out to the island of Chicago for

a day or whatever

not a day I should say

but for about 2

2 months and work with me on some commercials

and they taught me

a ton of amazing stuff I mean

I thought I knew composite until I met these guys

and you know

it's kind of intimidating when

you're talking to somebody who just

walked off the set of

you know or walked off compositing on

you know Star Wars Episode 7

and since then

I've worked on

even bigger films um

so just learning from those guys has been

incredible so again

you can see how painstaking this is

and I'm just sampling the local color here um

as you can see

and I can also come in here

and paint a specific piece here instead of range

so for instance

Sterling disappears right here

and come right here

I can do a Cologne here for this

and this is set to a single

but I can also set this to a range

and set this from

current frame

which is frame 40

all the way to frame 93

so any actual paintbrush stroke that I

put in here

that's what it's gonna do

so I'm gonna go ahead and just

do my best to sample the local area here

like that and now you can see as I

scrub forward

it basically goes away

so that's a lot of work when you think about it

and some of these you know

usually have a darker color of green as a tracking dot

for the sake of 3D tracking and so forth

and that's you know

it usually will

go into the key

but it'll create

artifacts that swim along the

edges of your actual scene

so we're gonna be taking care of those with

another crazy technique

but before we even do that

um I wanna go ahead

and just talk a little bit about

the balancing of the actual green screen here

so commonly

you can do all type of techniques using gradients

if you wish

whatever you prefer

to actually set up

and balance out the screen

you can see if I bring

slam the gamma down here

you can see

very clearly that we have

two different shades of green here

we got a darker area

where we didn't have any

actual light covering this area on

the green screen

I did this purposely so that you guys

are dealing with

the worst case scenarios

and you can see

just by looking at it

it's like wow

this is a very

heavy difference in cromanence

and if you get too dark

then you're basically doing with black pixels

which don't key at all

if you get too bright

you're basically doing with white pixels

which won't key at all

if you're trying

key green so

you gotta be careful on whether or not your

actual color green is

too close to 1 or

too close to value 0

because that's gonna actually give you

all types of trouble okay

so with that said

I'mma talk a little

bit about this

sucker here

this is a PNP

screen clean um

I believe it's by Pixel Fudger

I think they're called

I'm not sure

the name of the

it's basically

if you go to Wikipedia

you can stall

but this is independent by itself

and should load up fine

but it's the

screen cleaner

and this is pretty cool

so if I take my plate shot

and plug it in here

and just put my viewer to it

and then wow

you can see a huge difference

now I'm gonna go ahead

and hit d to disable this

and you can see

I can actually just come over here to my screen color

and click and choose

a color that's

not too bright from

the original

and not too dark from

the original

so I'll choose a

screen color

of somewhere in

the middle here

I don't you know

like that so

now I'm gonna re

enable this

and I can see it's kind of taken that

and kind of

it just basically balanced it all out

but keep in mind

anything you do in

compositing

you start messing with

the image you are

gonna be giving

yourself some headaches

because you could be creating

artifacts along

the edges of

the character

you could be losing

detail like

for instance

in the hair

hair could be

kind of depleting

anytime you do

any digital manipulation to something

you get you

tamper with it um

or I like to call tamper

and God's domain um

you will definitely find that you're

you're doing something

the image that

you might lose

the original um

image and we

don't wanna lose

anything like these

motion blur areas

um and anything like that

so this did balance it

out a little

bit if I bring

the contrast down

still still a

bit of a difference there

but you can

see if I kind of turn this off and on

there is a little bit more

consistency through it

so again this is a nifty tool we'll be using throughout

our tutorials as a screen clean

we're gonna be using a lot of plugins that

you get through Wikipedia for free um

and just kind of go through that

so it also has

a mask and also a clean plate information here as well

so let me talk about one other way to do a clean up

safe for tracking dots and so forth

so we have our d noise

I'm gonna get rid of this roto paint for now

and let's move my screen clean over here really quick

and just move some of this stuff out of the way here

some of these shots

I just wanna stick with Sterling here

and if I take the denoys and I go

I'm gonna first create a roto

and the roto doesn't have to be attached to anything

can be off to the side here

and I'm gonna find all of these obnoxious tracking dots

that I don't like

so for instance

I'm gonna go ahead and roll around this

I'm gonna get as tight as possible on this by the way

so get as close as you can

but not too close

like that you could literally draw it if you wanted to

you can draw it around

and then I can come over here

I'm just gonna grab around this guy

like that who else is got a troublesome spot here

there we go all right

so I'm gonna go ahead and

this guy right here and again

I wanna get as close as I can

to these things

I purposely made this green screen an absolute

mess by the way

so I'm just gonna go ahead and jump over here

and how about some other troublesome areas

maybe this this little guy

over here is

could be a troublesome little piece

this is actual background

so I'm not gonna deal with it um

I could go ahead and just shoot for these pieces here

here we go and let's go ahead and shoot for this

what the heck of the shoot with this guy

see what we get

there we go

so I basically rode odor

created an alpha for all of our troublesome little

dot areas here throughout our shot

and we're gonna go ahead and

use a technique that actually uses a unpreemolt

premolt edge blur

to sort of shrink in or sample the outer areas

and kind of suck them in like a black hole and then

kind of blend this thing out

it's a pretty neat trick

so the next step we're gonna do here is

we're gonna take this and invert it

so we take this alpha image

you can see if I kind of look at it

so I'll putting alpha information

and we invert this

and let's go and take a look at it

there we go

so we got an invert and we're basically

the opaque areas are what we're gonna be affecting

in this case will be this weight area here

so we kind of take a look at throughout our thing

let me hit s for settings by the way

my full size format should be set to

my 4,000 by 2160

it's off the screen

but you wanna make sure that's 4,000 by 2160

otherwise you're gonna have errors

and also by the way um

I just wanna mention your project settings

uh my current folder is in my d drive

but you would go ahead and just click here and

basically put this

to the folder from which you downloaded off my website

so that all of these is basically basing the

referencing via that where the new script is

so it's really cool

that way when you load these files up

you know you're not getting errors

and having to repap this by clicking here

so um you should in theory

not have any problem

alright so I'm gonna go ahead and make a merge node now

and we're gonna go ahead and put that right here

and I'm gonna

plug this B into the original image and a into this

and I'm gonna set this operation to mask

so then take a look at it

so you can see if we take a look at the image

here's the original

here's this now right

so it's creating a mask

and I'm gonna add an edge blur

right here which obviously is gonna

blur the actual Alpha edge

and I'm gonna really crank this up to say oh

just try 22 for now okay

and then I'm gonna go ahead and unpremolt this

I'm gonna go unpremolt and click on this

and you'll notice nothing is happening

and that's because if we look at our original footage

and poke around here um

we don't have an alpha image of hit a for alpha

you can see this image comes in

uh this actual DNG image has no alpha in it

so we actually have to come in here

and turn on auto alpha

so it inherently creates an alpha image

so then when we get to the merge node

you can see we do have an alpha channel

now that the overlay is correct

and I wanna go to the edge blur

it's blurring the edge

and then when I come to unpremult voila

it is cleaned up a lot of the edge work here

as you can see

pretty amazing

now you don't have to have the denoys

actually at the

usually people take care of this beforehand

so for instance

I'll go ahead and plug

this guy in

and then at this point then you would add your d noise

this is just clean up work

so I'll go ahead and put this

source noise

and we would come here and we'd be good to go

you can see it's looking really really nice

now again it didn't solve everything on the overlap

so if we come over here and watch Sterling go back

throughout the process here

that didn't take us long at all to do by the way

but we have to be aware that

there is there's obviously gonna be

an issue here when we have overlap

so if I go ahead and poke around

again I can just hit a for alpha here and

kind of see where this is hap this is happening here

so you can see we're gonna have all types of weirds

if I can find a frame here

actually let's just go back to original footage

there we go okay

so we we currently have you know

this scene here

let's go ahead and see how the it resolved

the detail didn't do too bad actually

what it's doing is

basically taking the information from above here

and here and kind of sucking it in

so you can see it's done a pretty amazing job

let's go ahead and take a look at other problem areas

so let's go ahead and find a frame where

his hair is maybe

overlapping here

here we go so just poke ahead

there we go

so we got that

let's see how that resolved it

okay it did a decent job

you can see we got this sort of wisp here

so what I'm gonna go ahead and do is

add a roto paint to just do some slate work on here

less work than I would have done before

so let me go ahead and put the dot node here

by hitting dot period

and now I can go ahead and take this Roto node

and just do some slight

perframe based

clone works again

I'll make this

big I'll put my hardness down to zero

and see if we can

kind of clean this up again

I'll put my opacity down to something

maybe like point one or something

and see if we can kind of clean this up

just briefly see

I didn't have to do a lot of work

but it's enough that the audience is not gonna notice

if I go ahead and play this through right

they're gonna

they're gonna just assume it is and it's a chatter or

sort of like moving edges around the corners here

there's a little cartoon called Doctor Katz

you should look it up on YouTube

K a t Z and you'll see

how if you see chattering along the edges

it's a failed key

it's also failed paint work as well

so that's it in regards to clean up

we got we have

plenty of other stuff we're gonna do in regards to

quote unquote clean up and making our plates look good

in fact one last technique I wanna show

you guys is actually we're gonna

get involved with a little bit of the keying already

and we're gonna talk about the most

popular key years IPK

gizmo color

and also key light

but this is a little process I'm gonna show you guys

that actually cleans up even further

so I'm gonna

I've got my de noise now

I'm gonna definitely have to do this

after my de noise

I'm gonna use keying to

kind of a rough key

to basically clean this up even more so

I'm gonna go ahead and pull this in

and the IBK color

if I go ahead and click on it

you can see if I just go ahead and try to build this up

we're gonna talk about this key a little bit

but basically it actually tries to create a

clean plate from the backing region

it's doing the same thing

kind of what we're dealing with over here

in regards to sampling localized areas

but again I'm just gonna come over here

currently have a size to sixteen

and let's see if I can kind of

basically gobble up as much of those

outlines of our character

I have the sector green

and the IBK color

as you can see

if I take a look at the original versus this

you can see what it's done

it's sampling

uh this area

and it's basically is if uh

Sterling got out of the way

out of the actual shot okay

um if I go to the gizmo

so you plug in the color here

to the gizmo

IBK gizmo again

you can get these by typing IBK

gizmo or color

and then you plug in the foreground here

you can see we get a key alright

that's all we're really doing here is pulling a key

so hit a for alpha

we have a key

um again pretty rough on the edges over here

next I shuffle out

the alpha channel

so if I go ahead and take a

look here um

now if I look at RGB

you can see that we've flooded the alpha

channel to the alpha

now I've inverted the image

uh which basically inverts the outside

and now I'm gonna go ahead

and what I'm gonna do is I create a constant

you just type in constant right here

and I'll just double click

and then I'm gonna put my viewer to the d noise node

and I'm gonna click on

an area here that

you know just

just generally the green screen area right

so what's going on here is it's gonna be taken the

background plate

or the clean plate created from the IBK color

and it's going to

minus from that

and what you see here is

the difference data between this flat

constant image

and this image here okay

so here you can see the difference

and now if I do

if I take that difference

and here is the actual file itself

you know inverted the mat

I can multiply that on top

so B for background a for top

and then I plus it

now we can see if I put this viewer to this plus sign

and go back to my d noise

look at the change that we have created here

um pretty amazing right

there's a huge difference

have we lost detail

yes we have lost detail in this process

you could see right here

we've lost some motion blur artifacts

we also have maybe introduced a little bit of a line

here um what else can we say here

so you can see all this

kind of half transparency stuff has kind of disappeared

we still have some motion blur

uh you can see here

we've lost a little bit of detail in here

it's sort of like flooded out almost

seems like this area has just been kind of flooded

uh with a green

it's it's kind of eating away at some of the juicy

motion blur and the motion blur the depth the field

the wispy here is all that stuff

is the important stuff that we have to hold on to

but this makes for one heck of a key

let's look at the difference between the original right

and the finish

so let's go ahead and take a look at it

guess see a whirl the difference there

so this is this can be good for running gun situations

obviously we have to mask this area out

and this is a little bit of problem area

but we've cleaned up a majority of these issues

we still have to do some paint work on

the intersections where

Sterling actually walks in front of the

these little points

but in general we've done some work now again

manipulation is dangerous because this manipulation

s starts to affect your edge

but these are just

some common ways to clean up your plates for keying

so just be aware of that