Illustrate Color & Light II: Color

1. Introduction and class structure: Hello, guys. My name is Denis Zilber, and welcome to our class two in Understanding Color and Light series. In this class, we will be focusing on color. Once again, a few words on class structure. This class also will be divided into three main subjects and each subject will be divided into three lessons. Each lesson, the first lesson will be a theory, second will be example, and third one will be the practice lesson, which will include our class project. In this class we will be talking about color of objects and what this color, what does it depend on. We will be talking about, once again about ambiance light. We will be talking about exposure, saturation and [inaudible] of color depends on ambient light intensity. That is more or less our program for this class. So, let's start with our first subject. 2. What does color of an object depend on?: Okay. Now if you work on the color theory, this is our spectrum. These are our colors. We have now colors. We have no more colors besides all these. You can easily unite them into one piece in this color wheel without any edges, but this is more or less more correct view of the spectrum. So, the theory goes like that. We have basically two temperatures of colors, hot and cold. All the reds starting from here more or less reds, oranges, yellows and maybe these up until this one are more or less warm. All these, this is neutral. Green can be either way it can be warm and also can be cold in some conditions. All these are called cold colors. So, according to certain lacking conditions, color can shift into warm or cold side of the spectrum. For example, if we have this red one when it's going more cold, when it's going colder it's going into purples. When it's going warmer it's going into oranges and yellows. Same with blue for example. Blue, any cold color, let's say blue. Blue color when it's going to warm, when it's shifting towards the warm side, it's going to greens, and the other way around when it's going to cold, more cold is going to to this to part. That is what we know before we start dealing with color ado. Just to know some terms. Warm and cold and neutral. Let's say we have an object. We have some object like this one, on the y background, this one. There is going to be some kind of sphere, light gray sphere. So, we adding here a y diffusion as we've seen in previous class. We're adding here also like absorption and the ambient occlusion, and some shadow, and here we go. We have more or less 3-dimensional thing here. What happens when we instead of white light, when we turn on some color light like blue. This one for example. Obviously, the white ball will also be blue because of the lighting because of the blue sliding and that is really obvious, really easy to understand but what happens when our sphere is also colored. Let's say will be red. Right now as we see it, we see red sphere on blue surface but we know that our surface is not blue, our surface is white and we also know that the blue liking is what made it look bluish. So, we need to adjust our red sphere to that extent, to that color, so it would look like red sphere on white surface with blue blue liking. What happens here is basically we're shifting our red color into more cold, into more blue part of the spectrum like here for example and also making it a bit darker because here this was white. It looks really bright, in here sorry and here it looks to be darker. So, what we do as I said, we were taking these red and we are making shifting towards cold part of the spectrum. Not here, but here and we are getting something like this and right now it looks much more I can show you. Okay. To show you the difference. So right now we have two versions, one version in this one we can easily see the difference between this sphere in the floor and we can understand how our brain interprets, and right now here we can easily see the difference between two reds in which right now we can easily see the difference between two red spheres and this sphere, more bluish, more cold one looks much more natural in this colored environment than this one. This looks like red sphere on the white surface with blue light on it and this looks like a red sphere on blue surface. That is a feeling that you need to develop in yourself. You need to understand the differences between the objects in with the same color in different lighting conditions. I'll show you a few more examples. So, these theory kind of maybe weird for your ears for a start, would be much more visible. 3. Playing with different lights: Okay. Now, in order to make things look more visual, more understandable, and more believable, I decided to create this simple scene in Maya, which is 3D software, and rendered with mental ray which is photorealistic rendering for Maya. Now, we have our default scene, we have basically one color for all the objects in the scene. We have one neutral elimination like in for this scene. Let's make things more complicated. Let's color things. Here we have four colors; basically we have white on the background, we have red, we have green, and we have orange. Pretty simple, pretty obvious. Let's add some color lighting, let's make things more blue, let's turn on our blue light. Okay. Now, you see everything changed, every object in our scene changed and shifted towards more blue part of the spectrum, here our colors would be red, green, and orange. Here our colors from the blue scene, from the blue lighted scene. You can easily see the difference between this color, this red, this one, and this, and this. You can easily see it in here, here it's in one part of the spectrum and here it's almost in purples. The same here, you have green is green and this one jump towards blues, jumps towards cold part of the spectrum. Same here, you have orange and here it jumps towards greens, towards the blue cold part of the spectrum. Same thing with yellow light, the very same principle works just perfectly in this scene too. All colors shifted towards warm part of the spectrum because of the warm lighting. Here we can easily see it. This was our initial neutral seen. This one was cold, this one got back to warm, not got back but it became warmer. This one neutral, cold which is here. Neutral, cold and once again warm. Neutral, cold, warm. Here the red light same principal works perfectly; neutral, cold, warm, yellow and red. Neutral, cold. Same green which is neutral right here. By neutral I mean not the color itself but our initial lighting condition. Here is we have white light which is neutral. So, that is our basic cover. What is happening here, we have same green which here becomes more cold, jumps here towards blue part of spectrum. Here it becomes more yellow. Just a bit. Now, just pay attention to these changes here, from here to here. If these even changes relatively to be initial condition on this beam so these more warm, more yellow than this. This one is more cold, and this shifted towards more towards red and became basically brown. Here, the same situation, exactly the same situation and we have orange, cold orange which became almost brown and once more orange, almost the same as initial orange and more red with more red tint of this color. So, based on these few examples, we have new rule in front of us. We have a really important rule that says that, color of objects depends on ambient light, not only ambient light because there can be many different situations with different lighting and different light sources. But color of any object depends on lighting conditions. In our case, in this lesson and almost in most situations, color of your object, any object that you paint, that you imagine, that you draw, will depend on ambient color and ambient light tint. That is really important to understand because, this understanding will allow you to paint shadows in the future, shadows correctly to understand what color of shadows depends on. Let's now switch to our class project and see how we basically implement this knowledge into our coloring scene. 4. Adding color to the scene: Okay. Remember this scene from our previous class? I took it as is and I made some little changes here. I made this carpet much, much darker because I wanted to eventually color the thread and I had to decide which color each object would be. So I decided that all these objects would be white stone, white marble and this carpet would be dark red. So I had to make it significantly dark. But besides this carpet, nothing changed. You can see and hear how we saw it in terms of light. Here, I just colored all the lights. Basically, this situation is absolutely natural and already gives us some kind of realistic rendering to the scene with only one colored light and all the rest is grey. That is correct. Physically speaking, that is more or less correct. Not exactly because this slide, if let's say it it has some more yellow to it, it would affect the ambient situation. I've put it this way. Ambient situation here in the whole scene. So the whole scene with only one white ambient light and one yellow light source will have much more yellow teeth but this is more or less a correct depiction of this situation. Let's now turn on our blue light. I decided that this scene would be dark, kind of evening scene so we will be able to see lights more vivid and more strong. So let's draw our blue evening light here. As you see, I use here a multiply blending mode which is in most cases, is not correct for shading objects. It is not physically correct. But in this particular situation, when we have mostly white and grey neutral color of most of the objects, it will work. It works well. Turn it on here and here and here and here and here and here and here. Now, in the next subject, we will see that this is not a correct picture but, this is let's say 80 percent or 70 percent correct picture because physically, it does all the job, it does calculates and takes into account all the lighting conditions. We have here since the previous lessons, we have here ambient occlusion. We have here all the ambient light diffusion effects and we also have a coloring effect on these objects from the ambient, from the lighting door, from the ambient light and what we have here, we have the blue light and it covers every object which is not affected by direct light by this open flame and it colors it with blue tint. Basically, what we have in almost any scene that you will paint or you will ever deal with, almost in any scene, you will have an ambient occlusion from from the sky from your room interior or any enclosed scene will have its own ambient light. You will always have these coloring tinting effect of when your ambient light gives a little tint to all of your objects in the scene. You can clearly see here, for example, in these red which is here when it's lit by the fire, it does look red more or less and here, it's almost black here. Why? Once again, because of the really dark and blue lighting situation in our scene. So basically, what we have to take into our toolbox from this particular subject, that in almost every possible situation, we will have our objects in our scene colored by the ambient light. In all additional lights, like here for example, all additional light sources, all additional lights and light rays, will be added on top of this ambient light. That is really important to understand that will give you a really physically correct and realistic approach to shading and rendering things. Let's switch to our next subject where I will explain why this scene is not perfectly correct. 5. Light intensity equals saturation : Okay. Let's say we have a surface here or some object and we have an observer here, us or just an eye. We have light that is bouncing from this surface into the eye and we basically can see all the information related to this object, including its color. So, the more light we see, the more information we get from the object. Here, we have some of few light rays that bounce from the surface into the eye. But let's say this object is red. Red is my favorite color. Okay. So, basically, each time light ray hit the object and goes back to the eye, the eye receives a color information from this object. We or the eye sees this object as red. But let's assume we just turn off some of these light rays. Let's assume that we make this light less intense with some kind of dimmer or we just turn off some of the light sources. What happens that here we are reducing the amount of color information from this object to that our eye receives, and that means that we will see less red from this. We will get less red information, less red rays, less red photons from this objects, and we will see less red and that means that the less illuminated your object is, the less saturated your object is. Color saturation of your object will be tightly dependent on how much this object is illuminated. So, illumination equals saturation. Light intensity equals color saturation. Let's see in some more examples. 6. Correct saturation example: Okay. Let's say we have a sphere. Let's paint it red. Or you know what? Let's paint it for a change, let's paint it green. Nice warm green. Okay. So, what's happening here, we have a bright and a dark part of the object. Bright and dark side of the object. This side is lit by our ambient light, and this part is in the shadow. What I did here, I just dropped some gray layer was really transparent airbrush, few strokes of transparent airbrush. I dropped it with Multiply mode, and this is not correct. Why it is not correct? Because as we know, the less amount of light gets into our eye, the less color information we receive from the object. Multiply blending mode doesn't do it. Multiply blending mode just multiplies one color information, one color property on the- basically acts as two semi-transparent themes one on top of each other. It is not correct physically. So, what we should do here is, and you can see easily that this color is basically the same color here, but a bit darker. That is physically not correct, because once again, the less we see, the less we will receive, the less light we receive from the objects, from shaded part of the object, the less color information we should receive also as well. So, this color is not correct, this color should be- First of all let's put it this way and let's make it like this one, but just slightly a little bit into gray area, into less saturated area. So, our second rule would be our second in this class- our second tool in our toolbox would be that because of the fact that light intensity equals saturation, all shaded objects will be less saturated than objects which are illuminated by sunlight source. It's a rule, it's law of physics, law or our universe. So, the less light we have in our shadow, the less saturated it will be. That is really important things to understand because many young painters, young sketchers tend to oversaturate their shadows and the whole light and shadow system. Light and shadow feeling just fall apart and then it looks bad, just simply looks bad. So, you need to understand that shadow will be always less saturated than the illuminated side of the object. Let's move to our class project and correct the mistake that we made in previous lesson. 7. Adjusting saturation in the scene: Okay, let's now, move one by one and just correct our two saturated blue shadow here. I suggest we start with our basic ground plane. So, we will be able to see if it feels right or not. I would do this 30 percent maybe or maybe even 40. Yes, 40 is good. Once again, minus 40 and here minus 39, here minus 40. I have to say something. Here, we're talking about physically correct rendering. It is nothing to do with your artistic choices and your artistic preferences. You may choose to make everything over saturated or you may choose to make things really strong colors, really screening colors. It's your right of course, but in terms of physically correct rendering, that would be more. This situation, when your shadow is much less saturated, then your light will be much more correct. Yeah, almost. Okay. Here we have our scene lead more or less correctly. We will add some lighting effect to it later and we will definitely add some materials and lights in next class. But for now, physically speaking, this is the correct depiction of this light consideration. When we have our dark blue ambient light and we have decelerated the ambient light, and we have our yellow orange tint of our ambient light source, not ambient light but diffuse light source. That is how this image, this scene, probably should look like. Once again, it's not the end. Someday, we are done with this scene yet. Okay, let's move to our new subject which is going to be exposure. 8. When it's too much light: Okay. Now, we already know what happens when we reduce the amount of light that is illuminating our object. We see it more desaturated or less saturated. On the contrary, when we increase the amount of light which is illuminating our object, like this, for example, twice, I don't know, 10 times more. Obviously, if we have some object which was, once again, red, for example. If we turn off the light, we will see it as black. We won't see any light, we won't get any color information from this object. When we turn on the light, we will see that it's red. When we start illuminating it with more and more light, we will see it brighter, and brighter, and brighter until we get to some situation when we may even get to the white color. The amount of light will be so big that we will see it as red; we will see it as white. What happens when we want to show in our image a bit more wider range of color? Because, right now, what we have is pretty much narrow range of the color going from really dark deep shadow or almost black to the full saturation of any color, not just red, and from the full extent up to the more brighter, brighter, and brighter to the white. But what happens when we want to show that our brightness or our color intensity is much greater than this white? In this case, we will use a glow. A glow on top of the white will show us and will show the viewer that our color is much brighter, that our colors is almost blinding. If you are going to look directly at the sun, you probably need sunglasses because you don't want your eyes to be blind. You don't want to lose your sight. So, that is happening because the light density is so great. So, in order to show this effect, you need to add a glow to your object. We will see it just in a minute how we do it. 9. Making things really bright: Okay, let's say we have a wide sphere on a gray surface and we want to increase the amount of light in the scene twice. For example, this surface is like a 40 percent brightness and I wanted to be 80 percent. Be much, twice brighter than it is now. But, we have a problem because our sphere here is 89 percent brightness and we can't jump over 100 percent because it's the maximum here. So, like if I do it 99, it will be like this, in this corner. So, we basically have to show that we have to increase the amount of light in the scene while showing the relative brightness of all the objects involved. We have two objects here, we have a sphere and the ground plane. And we have to show the audience, the viewer that our sphere is much, much brighter than the ground plane. So, what do we do? Okay, let's increase them on the right. Okay, let's make this instead of, once again it's under 40 percent, let's make it 80 percent. Right now we increased the amount light, that means that our shadows would be much more transparent because we have much more photons, much more light rays that are bouncing around the scene and therefore all the shadows will be less dark. So let's make it like this one. We will also have some diffuse light from the backlight, diffuse backlight which will be bouncing from the floor onto the sphere and this will look like that. Okay. And we also we'll have this sphere itself much more, much more illuminated. But it is still not the desired, not our target brightness because it was like 87 percent, it became 100 percent, 98. It is still not twice as intense as it was. So what we need here is to make a little trick. It's a trick, it's not the actual increase or intensity. It's a trick, we will be adding a glow to this scene. Like this one. I just take some white color and with the airbrush just paint it on top of the sphere. So right now, we have two, the same situation with different lighting conditions. This sphere here is overexposed. It's exposed too much more light and therefore it's glowing. So that is a trick and that is explanation why in fact we need this trick. Just to show objects that are illuminated, more intense way. So, that is our trick that we do when we have too much color of the theme. Some objects which are bright initially, which are initially bright will have that glow, and you can easily see how it is still white, the sphere itself is still white but it feels like much more white than this one and much more bright and much more, and it feels like glow. It feels the like exactly what we wanted to show, the overexposure of this part of the scene. So, that is our exposure effects that we use. Let us see some more examples. 10. Adding glow to the scene: Okay. Back to our class projects. Right now, we have a really dark scene with a really bright light source in the middle of it. At least, it's supposed to be really bright. We want to show it's brightness and we want to show that it's glowing. We want to show basically that it is a fire, not just something that is relatively bright. We want to show the viewer that this part is emitting light. So, we need to show it's brightness and it's overexposure. What I did here, I just placed few orange color blocks. Let's go this way. Color blocks with screen blending mode. In most cases, that does the job just perfectly. Orange or it can be even more yellow, which is not exactly what I wanted to achieve or even the red, which is not all. Obviously, not exactly what I wanted to achieve. Sometimes if you have, for example, some colored light source, you can make it, I don't know maybe green if you want and it will work just fine. In our case, it's supposed to be yellow-orange. So, let's leave it as orange here. One more thing that I should do here is, not that I really should do, but I can do and it will work also not bad. Right now, our flame here is colored. We have some gradient form from white to yellow to orange here and it's okay. But if we want this flame to really glow, we should probably eliminate all these color information. So, I painted with white and just drop orange color on top of it. This in screen blending mode and I also drop one additional colored layer with basically the same color, same orange, which will represent the light dispersion in the air. When you have a light, and you have a high humidity air, and the light is being dispersed through the air, you'll see much more significant glow. Here, and here, and here, yes. With these layers, you can play around as much as you want as it really depends on how much light do you want to see in your scene. We can make it as big as this. It's really, really hot light. So, that is our, by the way, if you want, you can adjust your eliminated sides of your objects according to this brand new light intensity, for example. If we turn this off, it looks we're dealing not bad. But if we turn them on, we will see that this one, we have much more light in the scene. So, all of these objects maybe some tweaks and maybe they need to be, I don't know, maybe more bright like this, for example. Or maybe we should add some more light, some more white light color here just to keep up with the new light intensity. Here it is. Well, it's plain white. Once again, I'm doing it because we significantly increased the amount of light here just by adding some glow. We showed the overexposure over the scene of this light and therefore, basically, all the lights in the scene would have to be more intense in there. All the lights would have to be adjusted according to the new lighting situation. Okay. That is more it for this class. We will in a minute talk about things to pay attention to. That is our exposure subjects, that is more or less it, and let's move to our conclusion, and eventually, to another class. 11. Things to pay attention to: Okay, guys, that is it for this class. Just to summarize it. Things to pay attention to, things to think about. First of all, there are two basic rules that we learned in this class. These are really important rules. If you want to understand light, if you want to understand how to paint, how to render your illustrations of paintings correctly in terms of correct physics lighting, you need to understand the two things that we'll learn here in this class. First is that, all objects in your scene will receive a tint. Sometimes, it will be really significant tint color from ambient light, from all the light interactions in your scene, in your university you're trying to depict. That will basically define the color of your object. So, there's no such a thing as red, or yellow, or green, or blue, or white. There are always white, yellow, blue, green, and red in some certain lighting conditions. You will have to take all these lighting conditions into account, and that is really, really important. You have to think about it. You have to understand it. You have to see it in your imaginary picture when you imagine something before you start painting it. You have to decide on your lighting conditions in your scene. Once again, it has nothing to do with your artistic freedom. It has nothing to do with your artistic choices. You can just throw away all these scientific stuff and draw as you like, as freely as real as you like, as crazy as you like. But, if you want to imagine an object and paint it correctly in terms of basics, in terms of light, you need to think of lighting conditions this object is currently in. The second thing you need to take into account, and which I think is one of the most important things that you need to think of is that, amount of light or light intensity equals situation. That means that all objects which are placed in the shadow, which are shaded or all, but all not eliminated parts of your objects would be much, much less saturated than parts that are illuminated. So, these are tools that you have from these class. Please think about them, think them through really, really carefully, try to understand, try to feel them. Observe things around you, observe different lighting conditions and different situations around you. Just look at objects around you, and you will see all these principles in the book. You will see all these principles actually working, and all these physical principles are true. So, as soon as you understand them, as soon as you see them, as soon as you've learned to see them around you, you will be able to implement them into your workflow. So, that is it. I hope you enjoyed the class. I really hope to see you in the next class, which will be dedicated solely to direct light and reflected light. Bye bye. 12. More Creative Classes on Skillshare: