All language subtitles for 2月29日 (9)

everyone

this is just a quick tutorial on how to create a

3d reflection inside of nuke

so this is not the 2d trick method that we can use to

create some fake reflections

these are actually ray

traced reflections inside of nuke

so if you could just take a moment and

hit the like button and subscribe

as it really helps with the YouTube algorithm

and

supporting the channel and trying to get started here

the channel is pretty new

I don't have that many followers or anything like that

yet but I hope to produce a lot more content like this

so if you guys

could just take a second and just do that

that would be really big help for me

so this is the effect we're going to be creating

we have a sphere here that's chrome

and this is completely fake and it's inside of nuke

we're not going in Maya

or blender or anything like that

and this effect is achieved entirely

in the re render node inside of nuke

so how do we do this

actually the setup is not that complicated

and I can actually provide you guys the

project file if you want to have some assets to play

with so I'm providing you guys with this footage here

just a little

astroturf area with a bench and then we have

a sky picture

and then we also have a 360 picture

and just a picture of the opposite angle

so

I'm gonna teach you guys

two ways to actually create this reflection

there's a cheap way

and there's kind of the right way

and the reason I like teaching both ways is because

you know sometimes you're in a pinch

and sometimes you don't have all the the

rendered assets that you need

or you might not have you know like a 360

picture like this

so what I'm teaching you how to do is

even if you don't have a

360 camera

or you are receiving this footage from somebody

else you'll still be

able to create reflection

for those shots using these techniques

using the kind of hacking

composing way

and as a composer you want to always be thinking

how to get the result no matter

what you have and being resourceful

so that's really important

so without dragging that on too long

let's get to actually how to create this effect

so

what we're going to do

first you need a 3d camera track

so I provided you guys

with that in the script file

so you guys don't need a 3d camera

track this this tutorial is not about

3d camera tracking if you need to find that

I have other information on that so

if we just start with our shot here

I'll just go over here so the track is here

I've basically

tracked this scene

and I've placed a card

on the ground plane of this scene

so again if you don't know 3

tracking I do have other tutorials out there for that

but if we just look through our camera let's just

merge this over

so we can see

and this put as a wireframe

so I'm gonna put a wireframe shader

just to show you guys

that there is in fact a 3

track scene here

so this is just a

the wireframe texture it just creates this kind of

you can see the polygons of your geometry

and I'm just putting that onto the card that I've

placed on the

ground plane so that's what we're going to start with

we have a ground

and a 3D tracked scene with a camera

so what we actually need to do

to make a convincing reflection is

we actually need to project

this footage onto the ground

around the object that we're reflecting

so if we look at our footage here

we see that this sphere is actually

reflecting the graphs that's sitting on and everything

around so all we need to do is

we put that ground plane into

3d space and we're going to reproject this

plate that we're filming with so this

video that we're looking through

we're going to project that onto the geometry

so that's the first step

so we're going to create that card

and that's been given so you guys start with the card

next thing we need to do is we create a sphere

so I put a sphere here

and just put it into 3d space in the right spot

so just a basic sphere and if I hit play here see

once we get once it caches

that this this video is kind of playing through

and it's kind of

the caching is not that great in nuke when you're

playing it for the first time but you can see the

video is rotating around

and projecting

that image onto the card so we're just using the video

a normal Project 3d node

we've hooked in our camera

then we plug that texture into a card

so now it's shooting that video out

from our camera

onto the card

next thing we're going to do is we want to put

a reflection node

on the sphere

and the other thing we need to do is

a normal scanline render

won't work for this

we're going to delete the scanline render

and I'm gonna create a node called re render

you guys might be familiar with this node already

but this tutorial still gonna be useful for you

because it's gonna teach you how to mix

projections and still get a reflection

so if you guys already know how to use this

still useful tutorial I think

so we're gonna plug in a ray render node

and we're gonna look through that result

and what we can see already is if we actually see

that this is already

kind of working this effect is sort of already working

we have a

sphere that is reflecting the ground around it

so we can see that

if we just disable the reflection and enable

it's actually ray tracing this reflection this is

so the difference between the scan line and the ray

trace

Scanlan render is

good for like elements and smoke effects and

some lights and stuff like that but if you're going to

create a reflection or

some actually

physically accurate shadows you need to use the

re render node

so okay so we're already most of the way there

but we want to make this a lot better and and

something that's important about

reflections is that they need to be spatially

accurate so if we

if you were looking at this ball

you would think that well

maybe we would be

reflecting more of this bench

and this bench is right next to the ball so

you know we should be seeing some of that

actually in this reflection

but the problem is we're projecting this entire

image onto a flat plane

so it can't accurately this ball

it can't accurately reflect

what's sitting next to it which is this bench

so what we can do is we need to start building

a simple model build of the geometry that sits around

this sphere

and we can do that just inside of nuke

so we're going to

just expand this a little bit

and I'm gonna create a cube node

and just plug that in

and I'm gonna scale it down because it's huge

our scene is kind of tiny

so I'm gonna scale it down

and I'm going to

set the divisions to 1 and 1 because I don't need

the cube to have a bunch of subdivisions

it just makes it harder to grab inside of nuke

sometimes

and what I'm gonna do is I'm gonna plug the same

Project 3D node

that's giving

our car detection

I'm gonna plug that straight into the cube as well

so now that image is being projected onto the card

and onto the cube

so if I move the cube around

you see that the texture is changing

that's because

we're not applying the texture as a texture

to the cube we're applying as a projection

so that just imagine that that video

is starting in the camera and being projected out

and it's wrapping around our geometry

so our goal with this is we need to kind

of line it up with

where it is in the real world

so the

easiest way to do that is to look at the projection

and line it up to the ground plane

so if you look at where this thing

starts on this flat plane

it's right here on this

card so all we need to do is take the cube and put it

put the front of the cube on the front of the real

box here so I'm going to line it up

and just slide it over until you start to see

that the box lines up so something like this

and

just gonna keep moving it

and you see

there's still you know a little bit of an edge here

on the ground

you see how the edge doesn't line up with the cube

so we know we just need to like

rotate our cube just a little bit

so I'm gonna take the cube

just rotate it in the y

so I'm just slightly rotating it

if you look at this edge as well you see this is the

if we look at the footage

this kind of curved wire is the edge of that cube

so in our 3D we're just gonna

take it and rotate it so that that

edge lines up with our fake edge

so I'm gonna rotate it like that

and just

line it up here

and one thing we can do

to also make this a little bit better is

I have a

lens distortion node provided to you guys as well

and we're going to undistore

our footage that's coming in

so that's just going to help a little bit

with and there's very little distortion on this so

it's not going to make a big impact but

that is something that is kind of necessary

depending on the camera you're filming with

so this was filmed on iPhones very little distortion

so next thing we're going to do is

that's sorry my Wacom mess up there a little bit

okay so we got that

cube lined up and we're just gonna shrink it

in the Z a little bit so I'm holding

command and shift on a Mac

to make sure that we have these scale

selectors there

I think it's that would be control shift on Windows

but I'm just scaling that into place

and making sure

at the bottom of our projection that is lined up

it doesn't matter if the

cube is sticking through the ground a little bit

you're not going to see that anyways

and then just scale it up

until it starts to hit the edge of the wood

so now if we rotate around you see it

actually lines up with the real world

so now if we

scrub through

we see that that kind of sticking

that image is sort of sticking

it's not 110 percent you know it's not a perfect lineup

but for the sake of this tutorial

it's gonna

it's gonna do good enough for our reflection

so I'm gonna copy the cube and I'm gonna do the same

exact thing for the other side

so I'm just gonna copy it

plug it into our scene and plug it into our project3d

and just slide this over

until we hit our other

little side of our bench here

and that's what we're gonna get

we've got something like this

and lastly we're gonna duplicate that cube

plug into our projection again

and we're gonna move it up this time and scale it

down in the y

and then scale it

in our X

and and just shift it over

so what we're doing is we're creating the

top part of the bench

and yeah nukes nukes um

transform tools still not the best

they really need to fix it but you know

they do not think it's priority

but yeah so this is

sort of close here

so you can see we're starting to basically rebuild our

real world in the CG

all right this is pretty good

so this is going to give something

to our sphere to reflect

so we're basically building the CG world out

just so that we can get it a reflection

of those objects in the proper way

and since this is closer

it's going to reflect differently than

something that's very far

so if we just take a look at a ray render again

and we go back out into the 2D

I'm going to close all this

now we can see we start to see

some of our pieces actually wrapping

and being close

so if for example I take the sphere and I move it

we're going to see as it gets closer to that

object it's actually reflecting it

so if I put it really really close you see

it's actually

you can even put it inside of it like that

and it's reflecting the edges

which is a pretty cool effect

so you

can do all kinds of stuff with this you could create

even a basic window

you can use the same technique and I'll show you guys

that

briefly after actually I'll just show you right now

it's very simple

so the same technique you could take

a plane

or sorry a card

and plug it in

let's close everything just to see we're good

so this is the same

principle of what we're doing

but a very very simplified

version is just a reflection

a card

and then just taking another card

I'm going to take the

actually sorry I'm going to take this 360 picture

they're not sphere instead so let's take a sphere

and we plug this picture into it

and we'll plug that into a re render

just quickly

you guys don't have to follow along with this one

it's just to demonstrate the principle

and let's pretty C node

scale up that sphere so it's big

and if we reduce the size of our card

we're gonna see what's happening

here so this is kind of hard to see

so I'm just gonna reduce size

so here's our little reflective card

and here's our camera

so that is automatically going to reflect whatever is

opposite of it

so if we're looking at this

it's hard to see a little bit but this

this card here is reflecting the sphere around it

so you understand

if you have a 3D camera track and you have a window

you can just stick a reflective card on that window

and then put another image

opposite of it

so it doesn't matter what image you use

so if you don't have

for example this 360 photo of the place that you filmed

it doesn't matter

you can still do this

and just take a different

photo that looks like it would

be something that would be behind the

glass at your filming

so that's essentially the principle

but we're doing a more advanced version

which is actually building it out into

the actual spatial scene that it is

so we can continue to build this

I'm not going to build out the whole thing

I'm going to switch over here to

what I've already done

so this is what I built out

and I just put this little barrier here the wall

you can even put the plant you see the plant is not

built out here this little pot for the plant

you could put a cylinder and build it out if you want

so that works for the foreground stuff

it works for all the stuff around

directly around

and that's going to give you a pretty good reflection

as it is

but next thing we need to do is

we need to give it something to reflect in the sky

so if we look at this

what we have just done and we just look at the result

we see that we have like a black sky

there's nothing to reflect

and so what we need to do is just any

picture of a sky I just took a 2d picture

and kind of grated it up and

put it on a sphere so if I zoom out look at that sphere

this is all it is just

straight on the sphere and I transformed it

to kind of scale it

so that's all we got

and now if you look at the ray render

we can see that we filled in that black

with the sky so this is the kind of like quote unquote

cheap version

and this will get you

if you don't have the

360 picture or anything like that

this is still gonna work for you

and you can still get a reflection

but I also did take this

360 picture so this is just better

because this is actually going to give us

everything else that was actually beyond

so we have our close objects that we modeled

so we have this bench and we have this little

wall here and everything but we have these really

objects that are further away

like the sky and the house

and the chairs

I don't want to model all those things

because they're so far away

from the camera

but if you do have a 360 picture

you can use that instead

so I'm gonna switch it over to that

because that's gonna give us a better result

so if I just take a look at that result

you can see that's a much much better result

and if you want to learn how to take 360 pictures

you can do it with any camera

you know you can take an iPhone

you can take an Android phone

and there's a lot of apps even to take 360 pictures

and any of those are going to

work for getting a reflection map

and you can plug that straight into your sphere

okay so this is working pretty well

you notice that

all these weird things are happening in the background

and that's just because

we're kind of looking at the picture that we place

behind

so what we want to do is we don't want to be

our final image we don't want to kind of

output through this ray render

we just want to get the ball

we just want to get the ball out of the ray render

so what we need to do is just off the side

create a scanline render I'll just do it separately

to create a scanline render plug it in the same camera

and then I'm going to plug the object

into the same sphere that we're

wanting to keep

and this scanline

render is just going to give us an alpha

of that ball

and we can use that to mask it

out from this re

render result

because we don't want all this weird stuff

and we don't want to reproject our whole environment

we just want to because that's going to actually

distort and blur our image a little bit

we want to have control

so what we do is we just mask that out

and then we have just our reflective wall

and this allows us to just

a over B merge it over our image so here's our

background and here's our re render result

that was we stenciled out

add our max to out and that's what we got

we have a reflective sphere

and lastly what we can also do is

another technique

so what we want to do also

makes it a little bit more convincing

we want to add what's called ambient inclusion

and we can do this inside of nuke as well

with the ray render

so if we just take a look at what that is

it takes a second to process there

so what this is doing is is creating a contact shadow

between the two pieces of geometry

inside of nuke so

that makes it a lot more convincing you see it

before and then after

it really feels like more of an object is there

so how do we create

an ambient inclusion this is very simple

so we can just take the same setup we did

we take our reflective

sphere the same geometry be used and just copy it

and we copy our ground plane so we just take those two

pieces of geometry

and we plug it into an ambient occlusion node

so you can just type it in ambient occlusion

and make sure you have it plugged into you know

like a constant or something like that

and we can just take a look at the result

if we look at the render

it takes a little bit of time to process that

and again so

you need to use the ray render node for this as well

not the scanline render

if you plug in the scanline render

this is not going to work

so the ray render is good for reflections and good

for this ambient inclusion pass

so this is a pretty good result

and the last thing we need to do is

if I just go back to frame

I'm going to go back to the starframe here frame 55

just to show you guys a problem that you might see

so we see that our geometry

if I so at the start frame here

we see that our geometry is kind of ending here

like the card is not long enough

so we're seeing the edge of the card

so either you can scale this card to be really

really huge

or you can just merge a white constant underneath

to just fill in that black hole

that's in the back there

and that's going to allow us to do a multiply

so if we do multiply

it's going to get rid of all the white

and keep the dark areas

and we see that that gives us our nice shadow effect

and lastly

what you can do to make it a little bit more realistic

if you want is I did a luminance key of the highlights

of the

ball we have

did a luminance key

and I pre multiplied that result

so we just keep the brighter areas of the sky

and I did an exponential below

and just screen that over

just to get a slight glow on the surface of this

chrome ball

to make it look a little bit more convincing

again if you were

doing this for real and you wanted to do the full

proper way of doing this

you would of course need

to make sure you have your lens undistort

and lens distort at the end

of your re render so redistort

so that would be something

that you want to make sure you do

and also you would put grain here as well

so you match your film grain

to make this more convincing

but this is just a quick tutorial on how to

make your reflections work

so that's basically it

hope you guys enjoyed

I'm gonna put the link in the description below

if you want to download the project files

and it's a pretty straightforward tutorial

and

the other thing I want to introduce you guys too is

I have a website here it's called Gumroad

Com Composing Academy

so if you type in this address gumro

com slash composite Academy

I have like a little email list I'm building up that

I'm gonna be releasing like much larger classes

on my own website and kind of off the side

so if you guys want to

keep up to date with that kind of stuff

that would be great

if you're interested

so yeah that's basically it thanks