Join Brian Bradley for an in-depth discussion in this video Adding a spherical fill light, part of V-Ray 2.0 for Maya Essential Training.
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So far in our scene, we've been working with a single V-Ray rectangular light, and we have looked at one or two obvious basic options and controls. As we now need to add some fill light onto our character -- of course, a single key light is not particularly flattering at this moment in time -- and because we do, of course, need to become familiar with how to actually create V-Ray lights in our scenes, let's go ahead and create a V-Ray spherical fill light for ourselves. Now, to do this, we could come up to our Create menu, just left mouse click, and come down to our a Lights tool, and you can see, down at the bottom we get number of V-Ray lights that we can add to our scene.
Of course, we can use the exact same functionality using Maya's Hotbox. I am just going to take a slightly different approach, so we are going to make a number of V-Ray tools and controls available to ourselves on our Rendering shelves. So if we just come up to the shelf tabs, and we just select Rendering, you can see I have made little bit of room here by getting rid of a number of Maya's own light types, as we are not going to be using those with V-Ray. And if we just open up our Render Settings window, come down in the V-Ray tab, come down to the bottom to this V-Ray UI rollout, you can see, if we just look at instructions, that we have the ability here to add a number of all tools to our Maya Rendering Shelf.
In fact, if we just click the Add button, we can see all of those appear very nicely in there, and you can see the last three options are the V-Ray light types. Now, of course, all we need to do is click on the V-RayLightSphere option, and we get a V-Ray spherical light added to the scene for ourselves. If we just come over to Move tool, and select that, you can see we can now position our light in the scene, so I am just going to drag it around a little bit. Just move it into position. I am just going to pull it little bit further out here, just so it's not quite as close as our key light.
Of course, we need to make certain that in our front viewport, we have set things up, so I am just going to use the A key to frame things up, and let's just pull that up, and again use the A key. I am just going to line up with the top off this podium here, just so we're getting a little bit of interesting shadow play; a little bit of uplight from our fill light. And I am just going to position it roughly between these two pieces of geometry, just so we have got a guide as to where our fill light has been set up. Now, of course, at this moment in time, we don't want to take a render, because we would be competing with our key light. Really, when you are lighting, you want to test each light in isolation to make certain what kind of a contribution it is making to the scene.
So I am just going to go to the Window menu; pull up our Outliner. First thing we can do in here is just rename our fill light, just so we know which light we are actually working with. So let's add that in there, and now if we select our key light, come over to the Attributes Editor, and just disable that. We can now have a look at the render we would get with just our fill light in the scene. So let's pull Render View back up, and we would get this as an end result. Now, whilst the level of illumination, the level of fill light on character, is looking quite pleasing -- we have got this looking quite nice for ourselves -- there are, nevertheless, a couple of issues that we would want to deal with.
First of all, we are lighting the rest of our scene geometry. That is not really something I want in this instance; I just want our key light to take care of that. And the same is true of this secondary shadow that we're getting. Oftentimes, double shadows and triple shadows in a scene can be very, very confusing for the viewer, so we want to make sure that only our key light is contributing shadows in here. We could, of course, use functionality of our V-Ray light, so let's just make certain that we are selecting our fill light. We could come down and disable shadows.
That would be one way of dealing with that problem, but of course, we would find ourselves getting some lighting artifacts on this side of our character's hair, because we would have no shadow stopping geometry; we would have nothing blocking the illumination, and would be an undesirable effect. Really, to take care of both of these problems, we just need to use a little bit of Maya functionality. So let's come up to the Window menu, and let's come to our Relationship Editors, and we want to come to Light Linking, and I am just going to work with a Light-Centric option at this moment in time. Of course, we need to select our fill light. Then I am just going to left mouse click, and drag down these options, just to make sure that nothing is added in there by default. And now we can just select our head, eyes, and hair geometry, and they are the only options; they are the only pieces of geometry that will be included in the illumination and shadow casting of this light.
So now, if we were to take a second render at this point, we would find that this is the end result that we would get. So much more pleasing; we can see just the exact effect that our fill light is having, and we are not affecting any of the areas of the scene. The final thing I want to do just to finish off our character's very quick and basic lighting setup here is just to add a little bit of texture to the lighting by just changing the colors a little bit. We are going to make out key light a little bit warmer, and we are going to cool down fill light. So with our fill light already selected, let's come to the Basic parameters here, and you can see, we can work with a couple of modes for changing color.
We could work with a straight color swatch; that is absolutely fine. As I oftentimes find myself trying to mimic real world light sources, so working with real world intensity units, and the Kelvin temperature scale. That's what we are going to do. We are just going to switch this dropdown over to Temperature, and I am just going to cool down the Temperature off our fill light a little bit. So let's set this down to a value of around about 7500. Of course, we need to open up the Outliner to select our key light. We want to turn that on, of course, and we are going to do the same: we are going to use the Temperature dropdown, but we are going to warm things up in here.
So let's set this to a value of something like 4750. As you can see in the color swatch, that really does warm up a light source. And now, if we were to take a render, this is the end result that we would get. So as you can see, we don't have any confusing double shadows, we've got very nice smooth area shadows, the hair is looking fine, we have got a warm light on the key side of our character's face, we have got this cool blue effect occurring over here, so all in all, things are looking as we would want them to there. And we've really demonstrated pretty much the basic toolset of the V-Ray light type to you.
We've worked with quite a number of options in there. One that we haven't really focused on too much, though, is this Intensity multiplier, and Units dropdown. Now, we just want to highlight to you the different options available in this Units dropdown, as the lighting units we work with will obviously affect how we are lighting our scenes; they will affect the intensity, and the illumination that we are getting from our V-Ray lights. Now, the default option is essentially just a straight color and intensity multiplier control; we are not working with any sort of real world lighting units here.
In this mode, the size of the light will affect its output, so a bigger light source in the scene will give us more illumination. The second option of Lumens gives us the total emitted visible light power measured, as you would expect, in the real world lighting unit of lumens. If we select this option, then the size of the light in the scene doesn't have an effect on its intensity. The values we give here, they give us a fixed level of intensity in the scene. Using the next option, we get a light intensity measured in lumens per square meter, per steradian. A steradian is just a measurement used when calculating solid angles.
When we use this setting, the intensity of the light will be affected by its size, so again, bigger light source means more illumination in the scene. The next option is an interesting one; one that can catch us out if we are not aware of how it is working: the Watts system. With this option, we get the total emitted visible light power measured, as you would expect, in watts. Now, we just need to keep something I mind here: this is not a value -- or this value doesn't give us the electrical power consumed by an object. So, for instance, a typical 100-watt lightbulb emits only between two and three watts as visible light.
So if we wanted to set our light in the scene to, in effect, mimic a 100-watt lightbulb, we would set this option to watts, but we would set the Intensity multiplier not to a volume of 100, but to a value of something around about two or three. Now again, this is a fixed value setting, so there is no relationship between the size of the light in the scene, and its illumination levels. The final option is, again, a real world measurement, measured in watts, per square meter, per steradian. With this particular setting, we again find that we have a relationship between the intensity of a light and its size.
So if we drop our light sizes down, we are definitely going to get less illumination in the scene. So, as you have perhaps gathered by now, the V-Ray light has really been designed to behave, in many ways, just like a real world light source. We can configure it to work with real world intensity units; we can use Kelvin temperature scale to give us a real world measurement for the colors. We can, of course, also configure it to work in any way that we want; that is the beauty of the V-Ray light type. So we have looked at the rectangular and spherical versions of the V-Ray light. What we are going to do in our next video is have a look at how we can take scene geometry, and turn it into a direct light source for ourselves.
- Installing and setting up V-Ray
- Using the DMC Sampler
- Understanding color mapping modes
- Adding a spherical fill light
- Working with the V-Ray Dome Light
- Using irradiance mapping and the Light cache
- Creating diffuse color
- Making reflective materials
- Creating translucency
- Ensuring quality with image sampling
- Controlling the V-Ray physical camera
- Creating a motion blur effect
- Compositing V-Ray elements