All language subtitles for 06. Generating deep holdouts

in this lesson

we will be discussing deep holdouts

and the workflow associated with it

in our previous lesson

we deep merged everything together

and it seems like a simple and obvious way to do things

but in the reality of production

things are never done this way

the reason they're never done this way is because

on real shots

you have a lot of elements

a lot of frames

and that means that you have a huge amount of deep data

the effect of this is that

when you're trying to composite

it takes forever

so we won't be doing things this way

and I'm gonna show you the solution

the solution

is to use

deep pulled outs

you can do this two ways

use deep pulled out or deep merge

using the hold out function

so let's find one here let's say for example

this character Grolo

what we want to do is

make a holdout mat

that allows him to be composited together

seamlessly as if

he was never rendered as a complete element

so what we want to see is what we were seeing before

when we deep merged everything together

but we don't want it to be deep

what you can do

take for instance

vegetation vegetation large 1

because the vegetation

in this element is in front of Grolo

Plug Grolo into the main

let's view this

and now we can see

switch to the alpha channel so you can see it clearly

now you can see that

the foreground vegetation has been held out

if I swap this probably won't see much of anything

let's pick a different element

maybe the background one

there we go

so in this case we can see this is Grolo held out from

vegetation large 2

so the way that we do this is

we want to take all the elements

except the element we're trying to make a holdout for

merge them together

and then subtract the whole element from them

so for example

we'll just take this deep merge set it back to combine

pick everything except the character

press y look at it

so with RGP

so here we have everything except the character

now we have just the character

so we're gonna subtract

this these combined volumes from this volume

plug the character into main

plug everything else into holdout

we end up with

is this which actually

ends up looking pretty similar to the first example

but that's just because of

where the character sits in the

in the scene

and what we need to do is do this

for every single element

we need to go through

and merge everything except the ground

and then merge everything except the trees etc

and then we end up with

holdouts that we can use for each individual element

I went ahead and did this already

so if we take a look

this is what it looks like

got everything down here

a lot of criss crossing pipes

but that's what it looks like

when you connect everything to everything else

in every combination

so if we take a look at what we've got

we've got the deep

we've got the AOVs

we recolor in this particular case

we compare here

this is actually a bounding box of 1922 by 18 by 1082

instead of 1920 by 1080

the deep had two extra pixels

in horizontal and vertical

so I just used a quick deep reformat to format

just to crop that down

we merged everything together

we made a held we made a holdout from it

so this has been held out

we go and look now we can see it's not just the beauty

it's the diffuse color

lighting raw specular

all of the other AAVs are held out as well

so what we're gonna do

is we're gonna go ahead

and render these out as precomps

then we're gonna render out every single channel

into one XR per element

we have now reached the end of the lesson

we've Learned how to generate holdout mats

from deep images

in the next lesson

we will learn how a pre cop work flow

will speed up our script