Headlights
This headlight shows a lighting situation that is not dealt with by a default light. This kind of headlight has a light bulb in its center that is then bounced off a highly reflective surface. This creates a spotlight effect where the beam of light emerges, not from o point, but from the face of the light fixture. To achieve this effect in Mayo, you can use the Decoy Regions you learned about in the Light Effects section of this chapter. Put a spotlight behind the light fixture, then make sure...
From RealWorld to CG Cameras
To better understand how Maya's CG camera works, it is helpful to compare it to a real-world cornera, fl real-world camera is designed to take bouncing light ond focus it onto the camera's film. In this way, cornera controls are closely linked to lighting controls. Maya deals with lighting and cameras separately. Below is a short description of why real-world cameras and CG corneras work differently. The first comeros used o hole punched in a box to focus the light onto o bock plote. This small...
Shrdow Limit
Light Radius and Shadow Rays define the softness of o Roytroced shodow. When working with Raytraced shadows, you should also set the Shadow limit attribute. For example, if you have o shadow-casting object with several transparent surfaces behind it, followed by an opaque surface, you would expect to see a shadow on the opaque surface. In order to see this shodow, set the Ray Depth Limit on the light to a value that is the number of transparent surfaces 1. Be sure that the Shadow limit in the...
Outdoor Lighting
For daytime outdoor lighting, your key light is the sun. A directional light is a good choice for this light because it has parallel rays. In an real outdoor scene, light will bounce which illuminates oil the surfaces a little. Some low-intensity directional lights pointing up from the ground can help create this effect. Shadows ore sharp and clear during sunny parts of the doy, while cloudy or twilight portions of the doy create less pronounced shadows. On o cloudy day, you have less...
Camera Effects
In a real-world camera, the camera causes various effects including motion blur, depth of field, and lens flares. In Maya, these effects are not automatically created. You must consciously turn them on to add them to a shot. Another real world effect is lens distortion. This distortion is a result of the curve of the lens that causes lines ot the edge of an image to bend. In Maya's pinhole camera model, this distortion does not occur. In real life, the camera's shutter speed is often slower...
Soft Lighting
when lighting a scene, you can create a softer, more diffuse look by choosing the appropriate light type and by softening the edges of the shadow and the penumbra. Lights that emit from o single point, such as spotlights and point lights, render with hard edges and strong shading. Lights that emit from more than one point, such as an area light, give a softer look as the surface shading ond shadows become less prominent. Multiple spotlights and ambient lights can also be used to create a...
Zooming pnd Dollying
When you want to animate the camera getting closer or farther away from the scene, you can choose between zooming, by changing the camera's Focal Length, or dollying the whole camera. These two approaches yield quite different results and it is a good idea to explore each technique. The purpose of this shot is to get closer to the street front. Using both o zoom and a dolly, you con see the different woys in which the perspective reacts. Chonging the comero's position with o dolly gives you o...
Fog pnd Optifx
Fog ond Opti-FX, such os Glows ond Lens flares, let you mimic the woy in which light reacts with the atmosphere, the camera's film back, and with our eyes. When a scene is rendered, Glows are calculated at the end ond composited onto the rendering while fog is rendered os port of the scene. Fog and glow ore covered in more detail in the Effects chapter of this book. when you apply Fog to o light, a shope is attached to the light thot is mopped with o volume shoder. This gives the oppeoronce of...
Casting Shadows
One of the most dramatic aspects of lighting is in the area where there is no light. Shadows add dromo to your scene while helping to anchor characters and props to the ground. If your character leaps into the air, you know what is happening because the shadow and the character no longer touch each other. In Maya, there are many factors that affect the look and quality of your shadows. You can choose from Depth Map and Roytraced shadows which offer different levels of quality and speed....
Dmop Filter Size
This value blurs the Depth Mop as the shadows are being rendered. This helps soften the edge of the shadows and create better anti-aliasing. The appropriate Filter size value depends on the resolution of your maps and how the shadow is focused on your shadowing objects. If you increase the Filter size, your render time will increase. If you increase the Dmap Resolution, you need to increase the filtering to get the same softness, which will olso lengthen render time. Very soft shodows con be...
Intensity Curves
This curve goes from on Intensity of 5 to 1 with o dip in the curve neor the middle. Correspondingly, the illumination diminishes ot that distance. The Intensity jumps up and down to put the focus of the lighting on the center sphere and the bock-ground. Other objects ore not offected. Another way of controlling the decoy on o spotlight is to use Intensity Curves. These curves let you specify the intensity of o light over distance in 3D space. You can use actual measurements fromi the scene to...
Light Effects
To create professional lighting effects, you have a number of tools at your disposal. You con turn on Barn doors or texture map the light's color or intensity to create Gobo effects and you can also use Color and Intensity curves to affect these attributes over distance- These effects offer you the kind of control a lighting technician needs to fully control the illumination of a scene. It is important to take your lights beyond the basic default settings if you want to achieve a professional...
Dmpp Resolution
This value determines the size of the Depth Mop. The higher the resolution, the more accurate the details of the shadow will be. As the resolution increases, the rendering time goes up. Therefore, you should make sure that your Dmap is focused as tight as possible on the shadow-casting object before increasing the Dmap Resolution. The Dmop Resolution ond Filter Size together define the softness of the shadow's edge