Original subtitles

[Autogenerated] in this module compositing efficiency.

We showed the methods for efficient work flows in the ways

that you can add and remove channels,

create better storage of both additive primary color passes and

non color data passes that store values and a single channel by

packing them into new renders at hold data in all four rgb a

channels in the first clip, we're going to go over the copy nut.

We're gonna find out about how copying channels,

layers and channel sets and how to move them around.

Within our cop, we're gonna learn about adding and removing channels.

We're gonna use both of these techniques to make a multi

layered single e xar file that will contain all the render

passes in all the channels.

Then we're gonna learn about how to pack the channels to be more efficient,

looking for redundancies and extra layers that really are

single images instead of triple channel images.

And then we're gonna use all these techniques to composite the helicopter shot.

So now let's jump in the nuke and look into further details of the copy node.

Now, here we see the copy note.

The copy note is designed to copy an Alfa from the A m put to the B inputs Alfa.

That's its default state.

But let's first.

Before we go into this that's going understand how

channels are represented in the viewer.

Let's hook up our viewer to this beauty pass.

Now what we see over here is RGB and a ____.

This channel drop down will show us our channels or what is sometimes

referred to his channel sets or channel layers.

We can either set this to none, which it will then display nothing.

RGB, which will Onley display the RGB or RGB Alfa or Alfa or other layers.

Now the other layers dropped down these air Other empty channel sets that

are available than nuke but do not contain any data.

Now let's go back over here We have our read files bringing in

the beauty and we can see that it has red,

green and blue but no Alfa.

And just like over here in the viewer for Hetty a key and I flip over toe Alfa,

we don't have one.

But what we do have over here is RGB image that is an Alfa.

But it to also has no Alfa Channel.

But the Alfa is represented in RGB space.

So for a moment,

let's throw down a shuffle note and we're gonna shuffle one of those channels.

One of these are G M B's into the Alfa Channel,

so let's choose the red because it's the first available channel.

So that way this Alfa right here, which is represented by the white box,

can be brought in as the A input and then copied to the B input over here.

Now, by doing this,

what we will see is will bring up the properties and you can see right here

that the A copy is copying the channel of rgb dot alfa,

which is this little box here.

And it's copying it to rgb dot alfa of the B input, which has nothing, sir.

Image coming out of the copy nut should now have an Alfa when I hit the a key

or we can hit em to overlay the Alfa on top of the RGB.

I did this thing where I put a shuffle node to shuffle the RGB into that.

Now we could remove this and get rid of the shuffle and

reconnect it and get the same results.

But this time it gives us an error because it's missing the input

channel because this does not have an Alfa.

So what we need to do is we need to copy the channel either Red, green or Blue.

I'm gonna select Red.

So now it's copying the red to the Alfa and we can see

the map overlay now works again.

And if we have a we have an Alfa Channel Copy nodes can do just that.

They can copy a single channel from the from the A M put

into the what the B input container is.

We can also additionally copy additional channels so

we can select this and we can say, Hey, we want to grab also the Green Channel.

Where do we want to put the green?

Well, we want to put it in the Red Channel.

So what does this do?

Every actually re colors thean image because And this

is just kind of like a shuffle.

Even though that shuffle and shuffle copy existed,

we can also kind of do similar things with both copy as well as shuffle.

There's a lot of things that kind of overlap in nukes notes.

So let's turn that back off.

We don't need to do that right now, Layer.

Copy is a way of copying an entire channel set over very quickly.

So that way we can not only just copy an individual channel,

which is what these air for, but this way we can copy an entire layer.

So let's set that up.

All right, So I have a ambient occlusion pass over here,

and we have what we just already did to combine the

Alfa with the non Alfa beauty paths.

We're going to take another copy note, so let's create another copy note.

And But this time, we're going to set it up,

so we're gonna copy an entire layer.

Now, I'm gonna take this over here, and we're gonna create a brand new layer.

So we're gonna copy the red of this input,

and we're gonna send it to a brand new layer.

So let's create a new channel and we'll call this a Oh,

that red, create new layer.

Say yes.

So now this is copied this into a brand new layer and weaken.

Also, tell it to copy the green copy of the blue.

So let's go ahead and do that but we're gonna have to create those

additionally as well a o dot green new you blue.

And now we have our rgb a There's Alfa and if we go over to the drop down,

we should be able to see a Oh, and there it is.

There's a Oh, now, it took more work than we really need to to create that layer.

Copy.

So let's create a shortcut.

What we're gonna do now is we're gonna get rid of that

and we're going to create a new layer,

and we're going to do so by using a shuffle now.

So I'm gonna shuffle the ambient occlusion into a

new layer that we will call a O.

So now it takes the rgb a It shuffles it into the a a layer.

But now let's go back to RGB A.

Go back to here and we're going to create a new copy.

We're gonna copy A and B and we're gonna disable the channel copy,

but we're going to use layer copy.

We're gonna copy that layer ao includes that.

So now we've created a new layer and we copied it into the image stream.

And now you can see it is present in our image stream.

Now, in the next clip,

we're gonna go look at adding channels and removing channels.