Octane Daylight Environment Light
The OctaneRender® Daylight incorporates accurate environmental illumination using sun and sky models and integrates usage of "HDR / Texture Environment" textures.
Octane has a powerful DayLight Environment node to simulate Sky and Sun lights. User can select how to set the Sun direction, using the geographic data or using the Sun angles.
Longitude / Latitude: These parameters can be set to get realistic sun settings for the specified geographic location.
Month / Day / GMT Offset / Hour: These parameters can be used to accurately place the sun in the sky according to the date / time for the sun at the current longitude / latitude
Turbidity: The Turbidity can be used to adjust the sharpness of the sun lights shadows. A low value creates sharp shadows (like on a sunny day) and a higher value diffuses the shadows similarly to a cloudy day.
Power: The Power slider can be used to adjust the strength of the light. This can affect overall contrast and exposure level of the image.
North Offset: The North offset slider can be used to adjust the actual North direction of the scene. This is useful for Architecture Visualization to ensure the direction of the sun is accurate to the scene.
Sun/Sky Model Parameters
Model: This specifies which daylight model to be used as the current environment. The old daylight model lights a scene with spectral radiance assuming that the sun is moving over the horizon at a constant distance from the object. The new daylight model is used to simulate full spectrum daylight with the sun hovering at a varying distance from the tangent plane providing more sky color variation as the sun moves along and then bears shorter rays as the sun moves closer to the normal plane.
Sky Color/Sunset Color: These settings are used by the new daylight model to customize the spectral shade of light. This can affect overall mood expressed by the image.
Sun Size: This allows users to control the sun radius in the daylight environment.
Ground Colour: Controls the color of the infinite ground plane associated with the Sun Sky systems.
Ground Start Angle: Controls the infinite ground plane's height and position.
Ground Blend Angle: Controls blending the infinite ground plane with the horizon.
Background Texture
Texture: This allows users to connect a texture that will be used as the background and ensures that objects in the scene accurately reflect it.
Heading and Pitch rotations: This allows users to rotate and align the HDRI image
Importance Sampling: This toggles the importance sampling of the sky texture – similar to the importance sampling in the texture environment.
There are three (3) options, generally used when you have a HDRI Image loaded as a backplate:
Backplate Visible - Turns the backplate visibility On/Off
Reflections Visible - Turns on Reflections for the Backplate
Refractions Visible - Turns on Refractions for the Backplate