Light Settings

Reference

Panel

Properties ‣ Light and Shader Editor ‣ Sidebar ‣ Settings

Next to lighting from the background and any object with an emission shader, lights are another way to add light into the scene. The difference is that they are not directly visible in the rendered image, and can be more easily managed as objects of their own type.

Common

Light settings for all renderers.

Cycles

Samples (サンプル量)

For the branch path tracing integrator, this specifies the number of direct light samples per AA sample. Point lights might need only one sample, while area lights typically need more.

Max Bounces (最大バウンス回数)

Maximum number of times light from the light is allowed to bounce. Limited by scene-wide bounce settings.

Cast Shadow (影のキャスト)

By disabling this option, light from lights will not be blocked by objects in between. This can speed up rendering by not having to trace rays to the light source.

Multiple Importance Sample (多重重点サンプル)

By default lights use only direct light sampling. For area lights and sharp glossy reflections, however, this can be noisy, and enabling this option will enable indirect light sampling to be used in addition to reduce noise.

Light Portals (ライトポータル)

Area lights can also function as light portals to help sample the environment light, and significantly reduce noise in interior scenes. Note that rendering with portals is usually slower, but as it converges more quickly, less samples are required.

Light portals work by enabling the Portal option, and placing areas lights in windows, door openings, and any place where light will enter the interior.

野外のシーンに置いては光線の大半がバウンスせずに空中に拡散していくだけなので、ライトポータルは野外のシーンにおいては無用です。

Jay Hardy による白い部屋のモデル。