Page 590 - Kitab3DsMax

Part IV: Materials, Cameras, and Lighting Basics

and Rotate transform button. Spotlights always are displayed in the viewport as a cone with the light posi-
tioned at the cone apex.

Cross-Ref
Both Target Spot and Target Direct lights are very similar in functionality to the Target Camera object, which you
learn about in Chapter 19, “Configuring and Aiming Cameras.” n

Direct light
Direct lights cast parallel light rays in a single direction, like the sun. Just like spotlights, direct lights come
in two types: a Target Direct light and a Free Direct light. The position of the Target Direct light always
points toward the target, which you can move within the scene using the Select and Move button. A Free
Direct light can be rotated to determine where it points. Direct lights are always displayed in the viewport
as cylinders.

Skylight
The Skylight is like a controllable ambient light. You can move it about the scene just like the other lights,
and you can select to use the Scene Environment settings or select a Sky Color.
Area Omni and Area Spot
The Area lights project light from a defined area instead of from a single point. This has the effect of casting
light along a wider area with more cumulative intensity than a point light source. Area lights are supported
only by the mental ray renderer. If you use the Scanline renderer, these lights behave like simple point lights.

The Area Omni light lets you set its shape as a Sphere or a Cylinder in the Area Light Parameters rollout.
Area Spot lights can be set to be either Rectangular or Disc-shaped. Be aware that area lights can take signif-
icantly longer to render than point lights.

Cross-Ref
For more details on the mental ray renderer, see Chapter 47, “Rendering with mental ray.” n

Photometric lights
The standard Max lights rely on parameters like Multiplier, Decay, and Attenuation, but the last time I was
in the hardware store looking for a light bulb with a 2.5 Multiplier value, I was disappointed. Lights in the
real world have their own set of measurements that define the type of light that is produced. Photometric
lights are lights that are based on real-world light measurement values such as Intensity in Lumens and
temperatures in degrees Kelvin.
If you select the Lights menu or the Lights category in the Create panel, you’ll notice another subcategory
called Photometric. Photometric lights are based on photometric values, which are the values of light
energy. The lights found in this subcategory include Free and Target lights.

Cross-Ref
The Photometric category also includes a mr Sky Portal option that is used to focus lights coming in from an exter-
nal source. This feature is covered in Chapter 47, “Rendering with mental ray.” n

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