Lighting

Setting	Description
Show Area Light In Primary Rays	Makes area lights (Sphere Light, Rect Light, Disk Light, Cylinder Light) visible to the camera. This has no influence on their visibility in reflections or refractions (e.g. behind glass)
Shadow Bias	Configurable offset to apply to the shadow ray origin along the surface normal. Helps reduce self-shadowing artifacts in low polygon geometry.
Use First Distant Light & First Dome Light Only	The renderer will ignore all lights in the scene except for the first distant light and the first dome light (the ordering determining the 'first' light of each type is not user-controllable)
Hemisphere Sampling	Select how to sample the Dome Light. Options are: Upper & Lower Hemisphere: Samples the entire Dome Light sphere. Use this option when scene objects should receive light from "below" (below the horizon) Upper Hemisphere Visible & Sampled, Lower Is Only Visible: Use this option when light is mainly coming from "above" the horizon (the upper half of the Dome Light sphere) Use As Env Map: select this option to uniformly sample the Dome Light. This may lead to highly noisy renders (slow convergence) when the Dome Light contains small, bright spots When using HDRI sky textures, it is recommended to use one of the first two options, to improve convergence speed of the render
Baking Resolution	Select a 'power of two' texture resolution to use as a starting point for the texture generated when baking the material bound to a Dome Light (if any)
Dome Light Texture Resolution Factor	A factor applied to compute the final texture resolution for a Dome Light texture. This applies both to Dome Lights with a material bound to them, and those simply using a Dome Light texture, which might need to be converted to format different from its input format (e.g.: a cube map may be converted to a lat/long texture, or vice versa, depending on the renderer's choice)
Dome Light Material Baking SPP	Number of samples per output texel at which to bake the dome light (i.e. evaluate the Emission function of a material bound to a Dome Light, if any). For example, baking a procedural cloudy sky to a texture may require multiple samples to reach a certain image quality

Show Area Light In Primary Rays

Makes area lights (Sphere Light, Rect Light, Disk Light, Cylinder Light) visible to the camera. This has no influence on their visibility in reflections or refractions (e.g. behind glass)

Shadow Bias

Configurable offset to apply to the shadow ray origin along the surface normal. Helps reduce self-shadowing artifacts in low polygon geometry.

Use First Distant Light & First Dome Light Only

The renderer will ignore all lights in the scene except for the first distant light and the first dome light (the ordering determining the 'first' light of each type is not user-controllable)

Hemisphere Sampling

Select how to sample the Dome Light. Options are:

Upper & Lower Hemisphere: Samples the entire Dome Light sphere. Use this option when scene objects should receive light from "below" (below the horizon)
Upper Hemisphere Visible & Sampled, Lower Is Only Visible: Use this option when light is mainly coming from "above" the horizon (the upper half of the Dome Light sphere)
Use As Env Map: select this option to uniformly sample the Dome Light. This may lead to highly noisy renders (slow convergence) when the Dome Light contains small, bright spots When using HDRI sky textures, it is recommended to use one of the first two options, to improve convergence speed of the render

Baking Resolution

Select a 'power of two' texture resolution to use as a starting point for the texture generated when baking the material bound to a Dome Light (if any)

Dome Light Texture Resolution Factor

A factor applied to compute the final texture resolution for a Dome Light texture. This applies both to Dome Lights with a material bound to them, and those simply using a Dome Light texture, which might need to be converted to format different from its input format (e.g.: a cube map may be converted to a lat/long texture, or vice versa, depending on the renderer's choice)

Dome Light Material Baking SPP

Number of samples per output texel at which to bake the dome light (i.e. evaluate the Emission function of a material bound to a Dome Light, if any). For example, baking a procedural cloudy sky to a texture may require multiple samples to reach a certain image quality