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• So it should come as no surprise that it also plays a huge role in shadow colors

• Okay, so this video is a direct continuation of my ambient light and ambient occlusion lesson

• Мы видели, как огни окружения играют огромную роль в теневых значениях

• We're about to go full speed ahead from there. So if you haven't seen it, check it out first

• Let's recall our quick light ray diagram

• We have the Sun a light ray comes from the sun hits the ground and bounces back up.

• Oh yeah, and when these rays bounce they get progressively weaker. That information really helped us with our studies and breakdowns in lesson 1.

• But now we want to add color to the mix. So we've got to do a bit more analysis.

• Let's begin with the most fundamental aspect of how these reflected or bounced light rays interact with color.

• So let's redo this diagram with this green card here. When a light ray

• bounces off something, its color mixes with the color of that object!

• Light rays inherit other colors throughout their lifespan. Now as for the exact balance of these interactions, don't worry

• we'll get there. For now

• let me just point out something obvious: the world contains a lot of different colored objects

• So you can imagine there's a whole lot of opportunity for many subtle colors to bounce around.

• Let's start with just the sun, and kind of simulate the lifespan of its light rays. And I want to remind you:

• I'm only talking about color right now, not value. We'll bring value back into the conversation later.

• So the sun's rays come in nice and orderly and uniformly yellow like this.

• But when they bounce, the whole thing starts resembling the Wild West with colors coming and going from all angles and in all directions! And

• that was just the first bounce.

• These light rays will bounce again ... and again, and again - until they're simply too weak to be seen. And our little diagram here is becoming

• pretty cluttered. Oh, and by the way, I haven't even put in the sky yet.

• The sky is a giant dome throwing blue ambient light down into the scene.

• Those light rays are weaker than the sun's,

• but they bounce too, and when they do, their blue color mixes with the colors of other objects. Yeah,

• I know, it's daunting. But don't despair, I have some good news!

• You would literally have to be a computer program to keep track of all those light rays.

• In fact, we do have computer programs that do that: they're called rendering engines.

• I'll fire up a rendering engine in just a few minutes,

• but first let's take quick step into the land of color theory ... because something very important is happening here that I need to point out.

• So I've cropped in on our diagram.

• What I'm going to do is start sampling colors from these bounce light rays and

• painting them into this little panel that I've made down below here. Now. I'm only sampling the mixed colors.

• I'm not sampling the direct sunlight rays or the direct sky light rays. Just the resulting mixtures that have occurred. In other words, our

• simulated reflected light. And I say 'simulated' because the way light rays actually mix in real life is,

• shall we say, more scientifically involved than this. But this approximation will still allow me to make some important observations.

• Okay, the very first thing I want to point out, just aesthetically as I'm looking at all these ambient colors side by side, is that

• there is a pleasing effect to them. They feel

• harmonious. Or in other words,

• they just look like they belong together. That they have something in common that binds them. Which totally makes sense, right?

• They do have things in common!

• For example, the environment they all came from. Also the sun and sky light rays they all came from.

• It's almost as though the environment and the light source are the parents and these resulting colors are the children.

• Let's bring in our color picker so we can examine these relationships under an artistic microscope.

• So please watch this box as I start sampling colors. And I need to remind you:

• I'm still only talking about color right now. Not values yet!

• Okay ...

• so I'll start here and I'll just scrub through again. Watch the color box as I do this.

• Just kind of take general stock of what's happening. We'll go back to the beginning and just kind of run through this again.

• Now I noticed two things happening here. The first is the colors the hues themselves were all over the map.

• It was totally unpredictable where each color would end up. We found colors everywhere.

• And the second thing I noticed has to do with the saturation. That is, the amount of color present.

• The saturation level was generally within this range of the color picker.

• So even though we were bouncing around like crazy finding different hues,

• we were always within, you know, this kind of range in in here. And it's that aspect - this

• saturation aspect - or actually I like to term it the other way: the amount of gray in a color,

• that is a very important player in our ambient light discussion because grays link colors together!

• You see, it doesn't matter where the hue is on the color wheel.

• As we've just seen with our sample environment, the hue can come from anywhere but every hue or color you can think of has this

• gray area in common!

• And the closer they get to that gray the more naturally they can kind of weave, or

• modulate in and out of each other. And that's exactly how we can take all these colors and

• handle them without totally going insane! In fact, painting

• the ambient light is often my favorite part of any painting! It can be fun and

• expressive, so long as you have these principles in mind.

• All right. Let's now bring value back into the conversation and do some painting.

• You'll probably recall this sphere demo from lesson one. It dealt with both direct light from the sun and ambient light in the shadow.

• We're gonna do something similar here today, only this time we can't use a blank background like that.

• We need an environment to inform our color decisions. For the sake of demonstration, I'll use this photograph for my environment.

• I'll just drag my color picker in there so you can follow along with my color choices and let's paint a sphere into this scene,

• right on the path here. Now

• I will choose to make this a white sphere because white has no local color of its own. In other words, you know,

• its local color is perfectly desaturated and that's nice for our first demonstration

• because it allows all the color that goes into the sphere to be the result of either the yellowish sunlight rays or the

• ambient light colors that are bouncing around in shadow.

• The first thing I'm gonna do is

• establish a basic value block in to determine where the light and shadow families go. And of course

• I want to remind you that when you have direct light like the sun in this case, all those bounced light rays

• we just looked at? We don't perceive those in the sunlight! Remember from lesson one that direct light visually overpowers ambient light.

• So I'm just taking a light value, tinting it generically yellow, and that's really all I need to represent the sun.

• Now the first thing I like to think about, especially when I'm painting an outdoors scene, is where is the skylight coming in from.

• It's pretty obvious. It comes down from above. It's weaker than the sun, but still has some strength.

• So this shadow is going to both lighten and get tinted blue in the areas that are exposed upwards towards the sky!

• So when that sky light comes down, it's

• gonna hit this area of the sphere and it's also gonna hit this area of the cast shadow.

• The skylight will probably not get in here because it's way too deep of a crevice. If you remember lesson 1, that's where the ambient

• occlusion goes. So for now, let's just start by applying the ambient light from the sky to our painting.

• What I'm going to do is kind of pick a generic color for the sky. Now

• this is probably going to be too light if I went super hard with the tablet ...

• but because I'm using a tablet I can just press softly and

• mix these colors on the canvas as if this were an oil or acrylic

• painting. I can also sample, say, this color here ... mix it a little bit ... sample this color here ... mix it a little bit ...

• So even at this early stage

• I'm already starting to build up that intricate weaving of ambient light that is causing multiple shadow colors to occur.

• And I'll just show you a little closer.

• If I start sampling through these ambient light colors, you notice that we are starting to have those relationships

• of grays! I've painted the most blue up here,

• so the most saturation I'm getting is here.

• Which is still very low and therefore remains bound to the other colors. And down here by comparison,

• just based on the block-in I did, is warmer grays. But next to that blue, those grays that looked just dead before

• actually have some meaning now because they're playing off each other! That blue gray against this yellowy orange gray. In my judgment,

• there are two more areas to consider.

• The first is: the sun would be shining down here and hitting the ground all in here and those light rays would bounce up,

• giving a little more illumination to this area of shadow as well as more saturation.

• And then lastly, of course, we'll have to deal with our area of ambient occlusion,

• which will happen down here as we know from lesson 1. So I'm gonna tackle the reflected light coming up from this path.

• But which color do I choose? Well, I know that the sun is generally this kind of yellowish orange color,

• I also know that when it hits the path, it's going to lose a little bit of its strength.

• It'll also lose a bit of its color as it inherits some of the path's color. And the path is kind of a neutral

• earthy color, like a toned-down sienna color, maybe somewhere in this range.

• So what I'll do, I'll just pick a color that's again fairly grayed off - so it remains linked to all the other colors -

• maybe maybe a little darker. After all it is a shadow. We don't want to ever forget that!

• It's a shadow. And I want to remind everyone: I'm not a scientist!

• I don't I'm not trying to think of the exact scientific blending! I'm just trying to get some color in here

• I'll adjust this as I go, I was trying to get some color in here that is

• motivated by the environment! Now watch this I'm gonna switch to the smudge tool.

• I really like the smudge tool because it does a great job with soft edges and when you're talking about

• ambient light, soft edges are really appropriate because that ambient light is coming from everywhere. It's a soft effect in real life ...

• so we use soft edges to help mimic that in our painting. Soft edges also help you to transition between multiple colors.

• Now what I'm gonna do is just handle this transition area here. And I'm darkening this area a little bit,

• starting to think about ambient occlusion.

• I'm also using a slightly more reddish color just to continue on with these, like, sienna earthy colors of the path maybe bouncing into this

• part of the sphere. I

• might also want to try some greens! Like, maybe some of these greens from the environment

• might be coming into our sphere just very subtly. After all those greens are pretty far away.

• So they wouldn't dominate the reflected light.

• But just a little bit of influence of them will help inform this passage of grays.

• Another word for grays, by the way, is 'neutrals.' You might hear other people call them 'neutrals.'

• And then, while I have this brush selected, I'll just, you know,

• keep working the transition until there's a statement that I find interesting and aesthetically pleasing.

• And I am pushing the colors a little bit just for demonstration purposes. And on that note,

• I'm gonna push for a little more blue in the shadow.

• Just cuz I'm looking at the shadows in the background and I'm seeing that there's a cyan quality to them.

• Probably from the blue sky mixing with the green trees. But I don't have to repaint anything. Because I'm using grays,

• I can really just paint over these colors that are there and they will mingle. So if there's one takeaway here,

• it's that there is no one shadow color. There are multiple shadow colors across the same object!

• Going to some warmer neutrals here for the ambient occlusion,

• and again,

• the reason I'm keeping it warmer is because there's not gonna be enough skylight colors here to cause any

• blueish grays. Since the path's local color is warm, I'll just keep this warm. Don't worry,

• we'll talk about local color more later on. And then as a last effort

• I will grab an airbrush and set it to multiply mode.

• I'll pick a warmish color like this to contrast from the blues and just start to address my ambient occlusion area.

• Hopefully you remember from lesson one how soft ambient occlusion is.

• Here's a photograph of a sphere that demonstrates this kind of softness that I'm talking about.

• You can see that where the sphere meets the ground is more or less invisible to us.

• It's lost.

• And the reason it's lost, again, is because there are very few light rays to give us any information there.

• So as painters we soften these edges to imitate that lack of information.