All language subtitles for nuk231-class01

hello and welcome to nuke 2 3

1 compositing best practices

this is Victor Perez

and I will be your mentor for the following 10 classes

to show you how to improve the quality of your result

as much as the quality of the process

everything within the course

is going to be applied to nuke

so I'm assuming

you are already familiar with the subway

the first area I want to explore is the mind map

what's a mind map

well actually

is what you are doing within the note graph

so it's a way of a structure

an idea based on different concepts

if here for instance

what I did is just to create what is a basic comp

so I have 2 different streams

one for the CG

the other for the scan or the plate

and here in the CG area

I have two main streams

the one for the CG

and the other for the live action elements

okay so there are certain areas that they are sharing

like for instance

the crane uncertain

others that they don't need to share

for instance

the match grade

or the lens artifact

in this mind map

what I did is just to specify very clearly

what needs to be accomplished in the comp

in order to create this photo realistic effect

remember compositing is to put together elements

to look like they have been shot at the same time

with the same camera

under the same lights

so every concept in here is a technical step

so every idea behind this note here

has a correspondence with your technical skills

okay so once you have this idea in your mind

you are ready to start comping

but in the process of compositing

is not like opening

you can try notes

just to understand if this is working or not

before you start touching a note

I want you to have very clear

what you need to do with this comp

apparently there is a difference between the way

you create a mind map

and the way we are creating a comp

because of course

you know that

we are going to start the comp

using the terminals in here

so we have the final elements

and we need to process everything all the way through

to get to the final comp

when you are working on a mind map

you are starting with the final idea

and then breaking down everything

to get to the final stages that are

in this case

for instance

the elements

well actually

in the process of compositing

in the note graph

is exactly the same

the only thing is

you are performing the operations

from the last note

to the very first

but the map

in your mind

has already

all the steps in here

is just easier to start from the image

and process everything through

up to the end

okay in order to understand the concept of mind mapping

is going to be way easier

if we translate

this concept

to the note graph

but I want you to understand all the features

of the note graph

so every time we are going to read a sign

we understand what's the process

that is affecting

within the operation

in the note

because remember

every note within the composition

is representing an operation

but an operation

could be or not

a whole concept or idea

sometimes in order to perform a certain concert

we are going to need a few notes

let me show you an instance

here I have this

first image

yes a checkerboard

and here I have this great

which is performing

a beauty grade

and then I have another

which is a toe

that is performing a bass

and folk feature

of the feel negative

for instance

so each of these nodes

is performing an operation

and is conceptualizing an idea

or a step in the mind map

in order to accomplish

the whole shot

so in this case

just one single note

is representing a whole idea

the beauty great

the base on folk

but there are

other concerts

that are more complex

and they require more notes

so here in order to get

the chromatic collaboration

I got two notes

so that's why

I'm performing here a backdrop

instead of just pulling a label

within the notes

okay of course

you can put

the label in here

if within this concept

of the chromatic aberation

you have different steps

and you want to

separate each step

just in order to create

a more clear explanation

in the mind map

you are applying

in the note graph

so remember

simple concepts one note

complex concepts

more than one note

everything in here

is about being tidy

and synthetic

in order to understand

all the operations we are performing

on how the operations

are getting through the mainstream

we need to understand

all the symbology

you can get in a note

so let's start with the circles

with letters okay

so the first one we have in here is the e

E stands for expression

and means that at least

one of the knobs

inside the note

has an expression

an expression

can be or not

related to a link

to other notes

in case you get

another note

to be linked

you get this link arrow

which is usually

by the fault in green

and it has this

arrow in here

that is telling you

that safety

note that is

probably in there

is driving some of the knobs

that you get

inside this great note

so there is a call

which is a link

from another note in here

placing information

inside this

so that's why

this is the direction

of the link

but an expression

can be also

without a link

for instance

if you want to randomize

a value within a knob

you can access to that

randomization using

nuke expression

so that is going to place this E

without this

arrow of link

expression so

that's the e

then we have the a

a is for animation

and it's going to appear

as soon as you place

a key frame

in any of the knobs

that you have

within this note

okay just one

single key frame

one single knob

is going to create

this a to appear

okay so usually

when you are placing keyframes

within a knob

is because you want to animate that knob

so that's why

this is placing

a is here so

you have values

that are going to change

depending on

the position

in time you are

in the timeline

okay that's the a

then we have the m

m is for mask

and don't be confused with the m

and this arrow

that some notes have

when you have

this circle

is because the mask

is not being

catch from this arrow

is being catch

from the mainstream

so as soon as

you activate the mask

within this great

is going to appear

in here the m

and is going to disappear

this triangle

that you get

to expand to create

the new arrow

for the mask

we will see

another lesson

when is better to use

the implicit

method of masking

and when is better

to have the arrow

on the side

okay the bottom

finish here

you understand

that there is a mask

and together with this

you are going to get

here what's

the channel

you're using

for the mask

and don't look

at the first

don't look at the last

look at the

one in the center

that is the

one that is

telling you

what's the channel

you're using

for the mask

the other two groups

are representing in here

what channels

are you modifying

with this note

and in here

in the case

of the grade

and other color

manipulation

nodes you get

the channel

that you are

dividing by

and multiplying by

these channels

okay so this is

the concept of

un premotification

and then pre

multiplication

as you know

every color

correction you

apply through

a premupplied element

needs to be

performing in

a non premupplied status

and then after

the color correction

you prem multiply again

so in order to

avoid to add

a couple of

notes one on top

and one below

you can perform

that operation

within the great

or any other

color manipulator nodes

okay another circle

that you getting

here is the v

b stands for views

which means

in this note

you are getting

one string with

more than one view

for instance

in an steoscopic setup

so this is just

telling you

that in this note

you are performing

both eyes okay

um because I

apply a split

in one eye so

I'm getting

a different

modification

from the left

and for the right

eye this red

square appears

which means

at least one

of my knobs

within the node

has this split

between the left view

and the right

view okay then

we have the sea

clearly C is

for clone okay

which indicates

that this note

is a clone of other note

and where is

the other note

well is pointed

by this lining

here the brown

by the fault

of course you

can change the colors

of these and these

by using the

properties but

to be honest with you

I don't think

that's a good idea

because it can

get confused

so just stayed with

their standards

is going to be

way easier so

clones are different from

expressions

because in an

expression setup

you get a master

and a slave okay

so any change

you perform to a

knob master

is going to

be reflected

automatically

in the slave

but if by any chance

you change the slave

by another expression

or something like that

is not going to modify

never the master

so this is uni

directional okay

while the clones

are vidirectional

so any change you are performing in one note

is going to be replicated in the other note

and pay attention to the mask

for instance

because that is a quite common mistake

if you getting here

a string that is having a certain mask

and in here you are missing that mask

if you apply to this note

this mask stream

this other note is going to contain an error

because he's searching for a channel

that is not existing in its stream

so pay a lot of attention

when you are working with cloning notes okay

so those are the sequels in there

another important thing is this gray square

with the X in the center

which means that the mix in the note

and every note has a mix

just to deal

the intensity of the effect

that by default

is at hundred percent

and it's a normalized value

so it means that 1 is full effect

at zero is no effect at all

and then the more you are going towards 1

the more you are applying the effect

so as soon as the

the mix is not at 1

this X is going to appear

which indicates that there is a certain level of mix

between the original and the effect okay

then we have the name of the note

and this is something I would like to spend award

you should never change the name of the note

in case you want to put any comments

use the label instead

because in here

you can write whatever you want as long as you want

you can insert spaces

and you can start with numbers

but with the name of the note

first of all

the name needs to be unique

so there are no other notes in this script

that can be named great 1

okay so when you are applying setting operations

like for instance

Python calls

you need to call the note by name

so never touch the name

use the label instead

then we have the color codes in here

what's this color well

it's going to be really easy for the first three

so red channel

green channel

blue channel

then we have the white for the alpha

then we have this purple for the deaf

and here we have the magenta

and the cyan

which stands for U and V

in this case

is the forward set of channels

and in here

we have the green

which is other layers

so of course

you cannot put a color code for each layer

because practically

you have infinite amount of of layers

so those you have in here are the most common

and then for other channels

you get this green

but can you see that they are squares

and then we have rectangles

what's the meaning of that

well when you get a square

it means that

the operation that you are creating within this note

is not affecting this channel

or this channel

or this or this or this

is only affecting the channels that are rectangles

and for the square

the tiny ones are just bypassing

okay so in this grade

as you have in here

is just been applied to the R

G and B channels

and nothing to the rest okay

in this case

seems a bit redundant

because in the grade

you have this particular line

that is telling you the operation

but in other notes

like for instance the blur

is going to be quite handy to understand

in what channels are you applying the

blur operations

for instance okay

then you have the postage stamp

okay the postage stamp is something that is

allowing you to see a thumbnail within the script

okay there are other tricks to display images

and I'm going to show you later in this class

if you want to display the postage stamp

you can go to the properties in the note

postage stamp

and you can select

what's the frame

you want to display in this postage stamp

okay so in case you want a particular frame

where your image is clear

you're going to select in here where

then there is another thing you can apply to the note

which is this input

you can hide it

this is something that

to be honest with you

is not 100% recommended

because it's confused

so sometimes

if you hide the input

as soon as you deselect the note

the input is gone okay

so a good thing about that is going to prevent

that arrow to be disconnected by mistake okay

but at the same time

is becoming a bit mysterious

where this note is coming from

okay so I don't recommend that

then you have another thing

which is this catch

that is displaying this yellow line here below

so with this

what you kiss doing

is catching this operation

so in case you deactivate

or reactivate the note

the process of the viewer

doesn't need to refresh

discount line

so it's going to be already catch this operation

so it's going to be

really fast to display

every time you are disabling this operation

so those features you are displaying here

are all the possible flags

you can see

within the note graph

to understand how the note is behaving

we have been discussing

the question of the channel processing in here

so you get the rectangles

and the squares

but sometimes

you can just understand that

certain channels

once they have been used

you don't need that anymore

so every time

you don't need a channel anymore

please delete them

because it's going to make your come to go faster

especially when you are traveling

through the 3D space

using projections

and so on so

in case you get

like in here a beauty

and you already finished doing your operations

with the beauty

for instance

imagine I want to create

an ambinoclution effect

so I invert

now I apply the ambinoclution

and now I know

that this ambinoclution

he's not necessary anymore

and I'm not going to even use

the death channel

in this case

or any other channels in this stream

so the healthier solution

is just to go here

and then remove the channels

so in the remove note

you have two options

you can keep or remove

I prefer when I don't want to use

more than the RGBA set

just to keep

undefine it here

the RGBA set

so as you can see

in the symbolging

here you get

RGB alpha that is not process

said that is not process

and other channels that have not been process okay

but after that

and just keeping the red

green blue and Alpha

okay so there are no other channels

that are just playing around in my script

okay so in case you want just the classic 4 channels

you're going to use the keep

and if you want just to remove one channel

you go and you select what's the channel in here

is telling you what's the operation

which is removed on what's the channel you are removing

okay so it's going to be really releasing

so imagine that sometimes we want to emphasize

this operation

so we can use that backdrop

in my case I'm using a present backdrop

you can find it on Wikipedia is free

or you can create your own

the important is you preserve a certain thunder

just to get all the notes

with the same kind of operation

with the same color of the backdrop

and using also uh

icons for instance

that I find quite useful when you are far okay

so I understand that this is doing certain operations

okay so in case that sometimes you see that

your text is in the center and is not quite aesthetical

just to read

you can just replace that by removing this center

what's the meaning of this center

well this major than minor

than science

is actually defining the orientation of the text

within this backdrop note

so if I remove that

by default the text

is going to run from the left side of the backdrop

in the case of the sticky note

for instance

is the other way around

a sticky note

when you have different lines

is center so if you want to specify

that the sticky note is starting on the left

you put it in there

so now the sticky note is justified to the left

you cannot justify fins to the right

at this present time

and version of milk

okay so you can't in the center or to the left

and in case you want to add an icon

you can use this formula

so I'm going to put in here

open and close that

and I'm going to put

I m G

s r c

equals

and a double quotes

and I'm going to put

the name of a note that you have in here

for instance

transform okay

so by putting the name of the note

is going to apply its icon in the toolbar

okay so transform

dot PNG because all icons in there are PNG

and in this case

is this playing the icon of the old transform

okay so in case you want to to put another

maybe let's put the light wrap so light

wrap okay so

you can put any icons up the same way you can

specifying here

the path for any image you have in your hard drive

other things that I like

is to put the sticky notes with the same colors

that I'm using for the area I'm pointing at

so for instance

if I want to

put a sticky note that is looking at these resources

I want to use these

same color okay

so there is something here that is

linking everything

is way easier to understand

when the colors are semantical

remember when you are creating your script

you need to be clear

not only for yourself

but also for the people that maybe one day

needs to open your script

in order to perform any changes

that happens frequently

when you are working in the industry

that you start working on a comp

and then you are assigned to other shots

and then a few weeks later

you finish that shot

the client is requesting some changes

so probably by that time

you are busy doing other shots

so maybe the production is going to assign someone else

to change that script

so if your script is a mess

that poor artist

that needs to change what the client is requesting

is going to take

way more time to understand what you did

than to perform the change request

so be kind because probably one day

you're going to be the guy

that needs to change from someone else's script

so if we create some kind of standard

everything is going to be easier for everybody

another thing that is interesting

is the shape of your notes

and the shape of the note

and even the color

is telling you

semantically

in what area of the composting its belongs

okay so let's start with the classics

the rectangle

that is a 2D processed note

so every stream that you have in this note

is just a 2D process

usually the kind of the notes are not compatible

so for instance

I cannot connect

the grade to a card

but you can connect the card to the great is

depending on what's the information

that particular note is expecting

of course each note is different

but by the shape

you can understand

in what area of your composition you are

so notes with the round sides

are 3D notes

so as soon as you connect the viewer to that note

the viewer itself is changing to the 3D view

the same way

you have the scene

which is the quintessential note of the 3D

okay then you have groups

the groups are hexagons

okay so you can recognize

because both sides

are kind of a point of an arrow

okay and within a group

you can put whatever you want

I always liked

when I'm creating groups and gizmos

to create some kind of coral reminding

so when you have

for instance

a three notes

your 3D note is going to have the same color

as the other classic 3D notes okay

why other notes

like for instance

notes like this

that are handling channels

are the same color as

for instance

the shuffle

so colors are really helpful

to make a semantical sense of the composition

the difference between a group

and a gizmo

is that the group is kind of a bag

containing many notes

while a gizmo is just behaving as one single note

so you need to get that gizmo install

already in the system

and that is creating many problems

so what I always suggest is

when you are working in an environment

where you are sharing your scripts

just remember

always to convert

your gizmos

into groups

the easiest way is just to go in here

right click

Edit Note Group

copy gizmo to group

okay so that is creating

a replica of that gizmo

but now that's a group okay

keep that in mind

then we have a relatively

new group of notes

which is the

deep image compositing

which is half 3D notes

and have this kind of shape

so it's not

a completely

2D is not 3D

but is something in the middle okay

and that makes that

you cannot combine

this note with that

or with that

okay is just a separate area

of capacity

so in each area

you can convert

from 2D to 3D

for instance

in this case

you don't need nothing special

but if you want to

convert these 3D

element into a

to debut so pixels

you can use a scanline

render so that

as you can see

as soon as I place

that is giving me

see the rectangles

that are advising me

that this is a

to the process okay

with the deep image composting

you have exactly the same concept

you go in here and then you go to

for instance

deep to image okay

so in here you get again the rectangle

so that is up to the processor

in here I can attach a grade

because that is converting from the deep image process

to the to the normal process okay

the input and output

are designed to create groups or gizmo

so they are going to define any input of the group

but every group can have only one output

so you cannot get more than one output in the note

is something that makes no sense

because in any case

you can attach as many notes as you want to one single

okay so you don't need to represent that

with several outputs okay

so for each group

you can express just one single output

and by the way

the number of this input note

is what is going to define this name on this arrow

so if I change within this group

the name of this input

and instead of being one

I can call it

source for instance

now the name of this arrow is source okay

so whatever you put after the input or by replacing

everything is going to be display in here okay

so input and output

of course we get the dots

which is very

very important

and the dot is not only for arrows

you can also call the dots by pressing command

and you can place labels on each dot

so here you can say from

input okay so you understand that this note

it's coming from this input here

so this note

of course in this case

is quite useless to put something in here

but in the case you get a very

very far note

probably is going to be a good idea

just to place in here some kind of labor or note

yes to remind yourself where is this dot coming from

okay you can

just in case your arrows are getting over

you can do that

so you can place spaces

and that is going to layout the text below the arrow

okay so that's another recommendation

then we have another kind of notes

which is the particle

okay so he's having this round it areas uh

in here okay

those are the main areas of

uh compositine that you can get in nuke

and remember

the shape is telling you already what kind of operation

and not only

also the color

is telling you what kind of operation within the

to the process

for instance

you are performing

so everything that is a light blue

in this case

is performing a color manipulation okay

while they notes that are this yellowish

are rights or supposed to exporting out information

okay so when we are structuring a compositing

we know that sooner or later

we are going to use a note for sure

which is a merge

so a merge is the sign to put together two images

so that is going to define the flow of or script

remember that the structure of a script

must be as a tree

so everything is flowing down and straighten

so you get everything coming together

from every single area

just to be at the end in one single note

which is the great note

okay so remember the mind map

everything was starting from the center

okay so in here the structure is a tree

so everything is just going down

to converge in one single note

so there is a easy way to preserve this logic

by respecting a rule with the merch

which is every time you're using a merch

put your B input on top

which is called the mainstream

and then the a input is coming from the left

to the right

okay so using this

everything is going to be very very clear

even if you are looking at this picture

you know very clear

that this image is coming to be mixed

with this mainstream

and why the B is the mainstream

what I call the base

is because by the fault in the merch

is the input that is getting the meta data

and also the range

but not only

is the only input that is going to preserve the format

in case you get different images with different formats

the format that is

being preserved is going to be the one on the be input

even if you are not going to lose

the area that is outside the format

you are going to preserve the final format

as the be input

and this is something you cannot change

okay so in here

of course you can limit your boundary box

and we are going to dedicate an episode just for that

so you can decide

how do you want your boundary box

but the format

the final format of the image

is always going to be the one from the B side okay

then you have this mask input

okay so the mask is the input

that is going to come from the right to the left okay

and of course

sometimes happens that a note requires more inputs

than those three that you have in here

the only rule I can give you to forbid something

is that you never

under no circumstances

just black a note from below something

like an arrow going up

this is really

really wrong

so never ever

have an input that is going from below the note

if you have this situation that sometimes

in order to preserve one image

for different purposes

you can do this

even if he's not

aesthetically the most beautiful thing you can do

he's always going to be

way clearer than getting the input from below

so the inputs should be always from the top

or at least from the side

depending on the purpose of that input okay

when I said to preserve the structure of discrete

I can suggest that always

you can get

your flow from top to bottom

okay so yes

apply this concept in here okay

try not to get arrows going up

because that is going to be a bit confusing okay

and by the way

right now you can see that you have these

arrows that are highlight

why is because I have selected a note

that is beam process over

over and over this

if I select this

everything that is anchored

that note is going to be processed

for instance

in this case

this arrow is not being processed

because he's below this dot

so he's not in the process to get the merge

so every time we are selecting a note

he's highlighting all the notes necessary to process

the image you are going to display in this note

okay so that is going to help

in case you want to move

all the notes that you are viewing with the process

you press command or control

if you are in Windows

and you move that

okay so that is going to move every note

that belongs to the process

that you are getting inside this note

that you selected okay

so the pointing here is to use

as less notes as possible

so using a copy of your read

he's not wrong

but he's not optimized

instead of doing that

he's way better

but you just get

a narrow here

and you just get this point

so the process is going to be exactly the same

of course you can get a post

this is stamp as well

so this note

is just going to give you

the same aspect

but I don't like much

to use that

because it's getting a

the aspect of being another read note

okay some people also prefer

just to hide the input

so I'm going to press Alt H

so that is going to behave like that

okay but again

this is something I don't like much

I would prefer

to use a dot

I have that

instead of having

the second read

no that is just going to create

a second recall to the hard drive

just to read the pixels

that are contained anyway

in the same image

in here okay

use as less notes as possible again

um with that

what I mean is

if you want to perform uh

color operation

that can be accomplished with one grade

is going to be always easier

just tweak one grade

done applying

a correction

for one note

and then applying

another correction for the correction

of the note

and then another correction

and then another correction

because one day

when you are going to need to change

something in there

every change you're going to apply

is going to be another patch

to another patch

to another patch

that is just

going to over process something

that is going to be simpler

if you get just

one single process trick

this doesn't mean that you cannot

use as many notes as you want

of course you can

and you should

but use your notes wisely

don't spend a note

if you can accomplish

the same task

with a note

that you already have

in the stream

okay so the economy of the notes is going to help

as well okay

and be clear then

there are safety notes

that are known to be

really slow

so for instance

remember that

in the 3D space

you don't get

any lens distortion

because the beautiful cameras

are not using lenses

so in case you get

a scan line render

and then another scanline render

so I'm not using the process on

on top and yes

putting the instances

if you use two scanline renders

to prefer certain different operations

and then you need to apply

the lens extortion

if you do this

that is not wrong

but it's not optimal

so instead of using this warflow

okay you can use this other warflow

which is way better

which is using 1 lenses

torsion at the end

so for instance

every time you are creating a recursive process

something you are using for several notes

just ask yourself a question that is

can I use one process for everything

or do I need to separate that process for all

notes instead

so if you can apply one single process

you just go with that

at the same way

if you can perform the scan line render

instead of having two separate scanline renders

for the same scene

or for two different scenes

just go with one single scanline render okay

the same happens with the grain

if you need to apply grain

many times I've seen people using this

and this is just making everything slow

even if you are copying and pasting

and you don't need to change anything

but even when you want to change things

you're going to tricking here

and then copy and paste and go there

so again is going to be way easier

that you apply one single process at the very end

okay so the economy of the notes is also in here

um in this case

I'm using just the regular grain um

lenses torsion

but when you get a very complex script

and you are using other tools

you will see that every little counts

when you are talking about optimization okay

so the main thing now is to keep

the order with the merch

okay because the marriage is the one that is

getting the directions of my tree

in terms of composity

so everything should be like a tree

so in case you want to put

this is skyline render over that

is skyline render

which is your mainstream

I'm going to put in here

mainstream to create a simulation

what if I want to put actually

this mainstream over the secondary string

of course you can change

by pressing shift X

you're going to swap your inputs

so now the a input is in here

and the B input is in there

so you want this to be over that

but this is breaking the rule of the mainstream

so for that purpose

we have another

merge operation

that is going to be way better in this case

which is the under

so in this case

we have like

the reverse inputs

operation for the over

so that's why we have another

and another

so we can preserve the B input in here

and the a input in there

so the result is going to be exactly the same

which is this is going to be over that

okay but the point is

you get always the

being put as the mainstream

okay so in case you get different resolutions

or meta data

or something

like for a particular interest

you need this to be on the B input

you can use the under instead

it's time to start the misdefine

all the operations within the merch

so let's have a look at the merch operations

and before to start with the operation itself

I would like to analyze the note

because in here

you can specify

what channels from the a input

are going to be combined

with the channels

of the B input

of your choice

okay so here

you can specify

everything that is coming from each stream

okay and then

you have in here

the also merge

so in case you want to apply

the same operation

to other layer sets

you can apply in here

remember that the mats are going to be apply

following that rule

you are specifying the operation

so in case you use

for instance

a multiplication

and you get

a channel here

that everything is going to be black

in the other side

in the other input

everything is going to become black as well

or even if the channel doesn't exist

in one side

in the other side

is going to be considered as zero value

so that thing

needs to be taken in consideration okay

then you have the output

the output is just going to display

what's the channel

you want to perform

in the operation of the merch

so if for instance

I bypass the red

and I have a look at this

have a look at

the red is exactly

the same as the being put

so in this particular case

the red is just being bypass

okay so this is

in case you want to

apply something

just for the alpha

or any other layer set

you want in here

okay so by default

is in the same layer set

that you have

the a and the B inputs

so the classic

rgba okay so

let's start

now with the operations

so I divide

every note in here

into groups

okay so in case you want to have a look

at the operations

you have all of them in here

and if you want to learn

how to read the formulas

you have in here

all the legend

to understand

how to read that okay

but the two main groups

I separate the merge

are the commutatives

and the non commutatives

what's the meaning of that

in the commutatives

the a input

and the B input order

is not going to change

the result so

if you get a E here

or a in here

and the B in the other

is not going to change

so for instance

in the plus

as you can imagine

is just adding the value

pixel per pixel

from one image to another

remember that the merge

what is doing

is taking every single pixel

and combining

with the equivalent pixel

in the other input

with the operation we are specifying here

so in the case of the plus

if I swap my

inputs by shift x

as you can see here

the resort is not changing

except in the

channel thing here

in case you bypass

for instance

the alpha so

if I go to the alpha

in here he's going to take

the alpha of

the B input

so he's going to be bypass

in the a input

so nothing is coming

from the a input

in the alpha

okay so that's why

is taking in consideration

the mainstream

the B so always

I'm going to preserve

the B string on top

and the a coming from

the side okay

and I'm going to leave that

by fault so

plus is adding

the values from

one input to another

this is like maths

so the plus operation

is a commutative

so a plus b

is the same

as B+ a now

the multiply

the multiply

is exactly the same

as the plus

so is just multiplying a times B

which is the same as

B times a okay

so you have in here

the explanation

now you have the screen

and what's the screen

well here below I put you another operation

that is going to be easier to understand

which is I invert the B

I invert the a

I multiply then

and then I invert the result

yeah that's the screen

so the screen is actually an inverse multiplication

okay so here you get everything

do not get confused

when I said an inverse multiplication with the division

which is a completely different operation

okay so all screen

multiply and plus are called automatics operation okay

then we have an addict met mean

which is an average so he's

getting as many inputs as you are connecting here

so if I connect another

like in there

see that I can get as many inputs as I want

but if I disconnect that

the main input is going to be always the B

so you can get as many A's as you want

and then in terms of the average

you know that is the saying where your B or your A's

that everything is going to be like

the adigmatic average

okay so he's just adding all three values

and divide by the number of inputs you are in here

in this case

three by the fourth

as you are going to see in your script

is just two

okay is just creating an average

then you have the geometric algebra

the geometric operation

is quite similar to the multiply

the difference is in the progression of the values

in the multiply

the progression of the values has a constant difference

which means

the difference between each stage of this line

is a constant number

that we are adding to get this line

so the progression of

the decreasing intensity of the light

using the multiply is linear

and remember that the light within the new workspace

is always additive

so the multiply is actually representing how the

decay of light is behaving in a linear workspace

while the geometric progression

which is this one

is not having that constant difference of a value

instead you get a ratio

so the ratio between each stage of this curve

is actually a division

in other words

what you are getting in the geometric

is more or less the same operation of the multiply

but you are preserving the light in the brightest areas

if you have a look at the graphic in here

see that the progression of the multiply

which is this one

is totally linear

while in the geometric progression

the bright areas are still preserved

still the geometric progression is not as light

should behave in a linear light worker space

but these can help sometimes

when you don't want to lose that amount of luminosity

when you are applying to multiply

then we have the hypothe

the hypothe is exactly as the theory of Pythagoras

okay so in here you get exactly the same maths

as you can figure in here okay

the sum of the square of a and B

okay and then the square root of the result

that's the diagonal of the triangle

now in here we have a comparative

so the max and the means so is yes

keeping the maximum value from both size

I need here the minimum value from both sides

okay so it's comparing both inputs

see all those operations that I put in here

our commutative so is exactly the same

that you get the a input or the B input

the result is not gonna change okay

then we have in here the non commutatives

okay so in here

it makes a difference if you connect a or B

in one side or another okay

for instance

minus minus

is different

if you from this a

you subtract this B input

what if I want to perform a minus

but I want the B input to be this particular image

so I want to reverse these inputs in here well

for that purpose

you get the from

from a minus are exactly the same operation

but with the input in reverse

I put a note here just in order to remind you

that minus and from are the same

okay so if I reverse now the from

so now the a input is on top just for

demonstrated that this and this are exactly the same

and as soon as I revert that to the original status

this and this are not the same

okay so minus I'm from

then we have divide

and for divide

we have no correspondence from the B and a

okay so if you want to divide

these needs to be always the bean booz

okay now we have probably the most famous

which are the layering operations

the main operation of everything is the over

okay so for this instance

I get this star and this circle

so I put this star over the circle

okay really easy

and now let's put the other way around

let's put the star under the circle

which is exactly the same as the circle

over the star

okay so over and under are the same operation

with the inputs swapped

okay then we have the mat

the mat is very similar to the over

with the exception that the aim put

has not been promoted by

but see it's having an alpha

so this image that has an alpha

is going to be premortified

at the moment you are placing the over

of course doing this is exactly the same

as placing a pre multiply note after this red star

and then placing it here and over

but with this

with this mat

you are just earning one note

that you don't need to use

remember that the less notes you use

the better okay

so that's the mat

then we haven't hear a strange couple

notes that are kind of dark

so many people is asking around

why is this

this join and specially the conjoin over

so let's spend a few minutes with this

the this join

over has been the sign when you are working with CG

that has been hold out

in order to put elements in front of other elements

okay so when you have

for instance the star

and you get the circle

okay so imagine that you want to put all together

if you use an over and you put that and that

look what's happening

see because of the whole doubt

the areas of motion blur or antielius or soften

are getting

not enough density to cover one with the other

so in order to preserve the consistency of that edge

they created the

this joint over

so when the image has the holdout

this is going to fill the gaps

okay so q place that

and now everything is perfectly uniform

with the value of 1

as you can see here

okay so that is the

these join over

okay as you can imagine that these join over

has to establish

so you can put the B here

the a here but the result is not going to change

intense of the edge

because it's just taking and feeling the gap

from the intensity of both sides of the layer okay

so that is the

this joint over

the sign for holdouts

and then we have the conjoin over

the conjoin is a specifying areas of semi transparency

so in here imagine that these stars

is having a certain amount of transparency

as you can see in the alpha

is having a 50% opacity

so when I apply this 50% transparency

to a holdout in the other shape

you're getting here

this 50% of opacity

but now this is just creating that

if I put in here

this over now I'm getting the 50% of opacity of my star

but is mixing with a very strange holdout from the back

so it's getting a jelloish effect

because my image behind is not uh

transparent in that areas

that I needed the start to be completely transparent

so I want to display the background

to be semi transparent

not the back element in here

so if I use the over

I'm mixing the semi transparency from both

while using the conjoin over

is just going to preserve that amount of transparency

okay but from the a input

so in this area

as you can see here

now is performing that the image

the circle is completely opaque

and the image that is in here

in the star

is getting my 50% transparency

that is getting over my uh

circling here

so it's kind of a strange operation

but he's just mean to perform

holdouts with semi transpirencies

okay so in this case

as you can see

is just preserving all the soft areas

and the semi transpirencies in all pixels

okay so that's is the conjoined over

then we have the 8 up

the 8 up is going to limit the area of the over

just to the inside of the mat of the be input

so whatever you are going to put on top

this is going to be on top of the B input

and nothing outside

okay this is the a top

then you have the sure

so everything that is overlapping

is going to be transparent

everything that is not overlapping

is just going to be mix

okay so you just giving me this effect

of course you can play around with the images

and giving you

so you can just understand

more clearly

the formula you have in here okay

then we have competitive okay

the competitive is just making a difference

in this case

which is the more difference you are getting

from the a input to the B input

the higher is going to be the result value

so in this case

for instance

have a look at this pixel

this square here is just going to be black

and in here is black as well

so the result is going to be no difference

no difference is zero

zero value is black okay

so everything in here that is getting the same value

he's just going to display black square

the more is the difference

for instance

in here which is black and white

the difference is going to be a high value

the difference

in other words

is going to be kind of a minus

but the result is always going to be positive

so in case you get a negative number

in the minus operation

automatically

that number is going to be change in the sign

so it's going to be a positive number

so remember that

the difference is going to be very helpful to spots

differences between two status of a comp

then you get

the exclusion

is just calculating the variations from 0.5

so everything that is aligned to 0.5

he's going to display gas at 0.5 value

so the differences are going to be from 0.5 to 0

or from 0.5 to 1

so is kind of a difference

stabilize to the 0.5 okay

very helpful

when you want to apply

in combination with overlays

or embossed effects okay

then you have masking

and with the masking we have four options

and to be honest

is actually two options with the reverse of the inputs

so in is going to be using from the B input

just the alpha so the mat

and then is getting the a input

just to be display inside the mat of the B input

which is exactly the same as the mask

with the difference in the input

so if I do this

as you can see

this and that are exactly the same result

okay remember that in the masking operations

you are using the mat from one of the inputs

the one that is performing the the mask okay

so in the in is the B input that is getting the mat in

the mask is in the a input

and everything is inside

and then the other way around with the out and stencil

so everything is outside the B input mat

or in this case

outside the a input mask

okay so they are a couple okay

so when you want an input to be the main

you put it in the B

and depending on in what sense you want your operations

you use one or the other okay

then you have the color lighting

this is quite classic

like in Photoshop

this is the Color Burn or the color Dodge

so this is just getting things darker

and this is getting things brighter

using the bean boots okay

then we have the combined ariimatic

which is for instance

the overlay

overlay is going to be stabilized at 0.5

in terms of value

so at 0.5 is just doing nothing

so everything that is overlay by a constant of

0.5 is just not changing

so let me just

this plain an example for you so here you are

here you are

constant 0.5

so the image is not changing

okay and with the overlay

is there supplying a multiply when he's going below 0.5

and a screen when he's going evolve 0.5 okay

hard light is exactly the same as overlay

but with the input swap

so what was in the overlay

the a input

is now the B input

what was in the overlay

the B input

is now the a input

but at the end of the day

the maths in here are exactly the same

so is a multiply when the a value is below 0.5

and a screen when the a value is above 0.5

which means that things that are dark in the a input

are getting darker

and fuse that are bright in the a input

are getting brighter remember

overlay and hard light are exactly the same math

with the swap inputs

and the soft light

by the definition of the mineral of milk

is not as extreme as the hard light

so it's very similar to the hard light and overlay

but not as much strong as it was

they multiply in relation to the geometric

so you are not losing that much amount of light

and then we have the last operation in here

which is the channel replacement

which is the copy

copy is just taking the channels from the a

and placing them in the be input

so the be input in here

is just been overgrading by the a input

it can sounds a bit silly

but believe me

makes sense

when you want to take certain image

and just place in another certain format

in the same position

okay so you are using here

maybe just a few channels

but mainly what you want from the bay input

is not those channels

but the Automator data

or the format and other features of the main input

so here you are

all the operations that you have available in nuke

and remember

if you master the operations

everything is going to be way simpler

because you don't need to create workarounds

with your inputs

or with any other notes

just to perform the same operation

so that's all for this class

if you have any comments

questions or suggestions

feel free to post them in the forums

until the next time

this has been Victor Perez for FX PhD

thanks for watching