All language subtitles for 2. Layer and Channel Drop-downs

Now let's take a look at some of the Peripheral menu items.

At first they look like a bunch of archaeon symbols

so let's demystify them a little.

The first thing I'd like you to take a look at is the RGB dropdown menu,

right here.

If you don't see it, it might just be hiding itself,

and you can just slide the window to enlarge it a

little more and it'll come back.

So if you have this window slid, this is not the one we're looking for,

if you slide the window over, this is the tab that we're looking for,

it says just RGB.

Now I'll take a quick second to talk about RGB channels.

Each image that you're working with will contain four

basic channels by default: a Red, a Blue,

a Green, and an Alpha channel.

So if we go up here, we see that we can view our Red channel,

we can view our Green channel, we can view our Blue channel,

we can view our Alpha channel.

We can view the Luminance value, which is the level of brightness in a pixel,

or we can view our Matte overlay.

The Matte overlay is just showing the Alpha superimposed over the

image so that we can see what it's cutting off.

Now I'm going to turn that off by going back here and selecting RGB,

and I'm going to scan down here to an example that I've built

for you to talk about the RGB channels just a little bit so if

you haven't used them before, this should be helpful.

So right here I've created a full red constant,

this just floods the screen with a pixel value of one in the red channel.

This is a green constant, and this is a blue constant,

and then I've just made some squares out of them with Roto shapes.

So if we look at the red constant, I've got a little square of full red,

and you'll see down here that we have a full 100%

value of red in the red channel, and nothing in the green or blue channels.

Same goes for this green; we have a full 100% value

of green in the green channel, but nothing in the red or the blue channels,

and likewise the same with the blue: 100% blue,

0% green, 0% red.

Now, as I combine them, and combine them again,

what you'll see here is all of the squares overlapped,

and if we look here in the red by itself,

this is a full red pixel with no green and no blue.

Here we have a full red pixel, a full green pixel,

and a full blue pixel, and since all those colors are combined,

they just combine to be white.

Here we have no red pixel, just a green pixel,

and a blue pixel, and here we have just a blue pixel.

So if we go back up to the menu we were looking at before

and we look at just the red channel, you'll see this is just where red exists.

If I select green, this is just where green exists.

If I hit blue, this is where blue exists.

None of these have an alpha channel, they have different values of luminance,

so I'll go back to the RGB,

and now if we want to see the difference on the keyboard,

we can just use R, G, or B on the keyboard to see the difference.

So if I look at the green channel here, you'll see,

if I flip back and forth between them really quick,

you'll see the area that's affected by green.

Likewise, if I do the red, if I hit R on the keyboard,

you'll see the area affected by the red channel.

If I hit B on the keyboard for blue,

you'll see the area affected by the blue channel.

So just keep in mind that R, G,

and B can be great tools on revealing where the red,

green, and blue channels are interacting with your image.

So if we go back up here and we look at this picture of earth,

we see that this is where the red values are by hitting R on the keyboard,

this is where the green values are, and this is where the blue values are,

and if I hit B again, it just takes me back to the original image.

But you'll see that.

So if we see that there's a lot of blue in here because it's earth,

you see a lot of those values show up as white,

and we might get some reds here in these yellow desert values.

If I hit R, you'll notice that these values are very white,

and that is how you view the different channels in your Viewer.

So I'm going to show you a trick right now that you can use

your Viewer to view different parts of your comp all at once

using the ContactSheet Node,

and I actually didn't know that NUKE contained this

ContactSheet Node for quite some time, but it's become really helpful in my work.

So if you hit Tab, and type in ContactSheet,

and hit Enter, it's going to add this ContactSheet Node to our comp,

and I'll connect this at the end of the comp here,

and hit one on it to put it in the Viewer.

What it's going to do is it's going to take whatever you've

plugged into it and it's going to thumbnail them out here for

you to see all the different parts.

So you can pull out this triangle here,

and plug it into different parts of the comp,

and each one of these parts will show up as a thumbnail laid

out for you so that you can see as many individual pieces of

the comp as you want all at once.

And you can imagine how powerful that can be.

So for example, I delete this, and I hit Tab,

and add a new one, if we want to see what the end of the comp looks like,

and we want to see this earth without stars,

and we want to see what the earth looked like at the

beginning of the comp before it got its glow,

we could zoom in here and you can see the different parts.

In the next clip, we'll take a look at Viewer display modes.

NUKE has some powerful tools inside of its Viewer panel that allow

you to AB between two different pieces of your comp and see what

your work looks like on top to itself.