Environment tab

This tab collects all the details for specifying the surrounding environment of your scene. You can set a specific environment for Global Illumination calculations, specify an environment for reflective or refractive objects and the background itself.

Environment

Environment
Select from the following options.
None

Black.

Camera Background

Uses the environment from the current camera.

Sky Light

Uses a specified color/texture for the entire environment.

Image Based Lighting

Uses a specified LDR/HDR image as environment.

Intensity
Controls the intensity of the specified environment.
Visible in Background
Shows the environment in the background of rendered frames. The alpha channel will still store transparent in areas with no geometry coverage.
Visible in Reflections
Shows the environment in reflective surfaces.
Visible in Refractions
Shows the environment in refractive surfaces.

GI Environment

GI Environment
Select from the following options.
None

Black.

Camera Background

Uses the environment from the current camera.

Sky Light

Uses a specified color/texture for the entire environment.

Image Based Lighting

Uses a specified LDR/HDR image as environment.

Intensity

Controls the intensity of the specified environment.

Sky Light

Sky Color

Specify a color for the Sky Light environment. Suitable to select a constant sky color, or plug-in a procedural sky like a ramp or a more complex shader network.

Image Based Lighting

Image Based Lighting is both an algorithm to light a scene with a LDR/HDR image, and a simple environment for images. The IBL is by default set to act as a simple environment.

Image File

The image file to be used. You can use most image types, but you should of course use an HDRI image if you can, like EXR or HDR.

Turn Light Dome

The sphere that the image is projected on can be rotated around the up axis. The amount of rotation is given in degrees.

Swap Y <-> Z

Swap the up axis. By default Y is up.

Visualize

The HDR image will be visualized for reference as a sphere inside the Maya scene view. This sphere can only be turned around the up axis and is connected to the Turn Light Dome option. It is not visible in the rendered image and should be disabled before rendering.

Blur for GI

Pre-blur the environment image for Global Illumination calculations. Can help a lot to reduce noise and flicker in images rendered with Final Gather. May increase render time as it is blurred at render time. It is always cheaper to pre-blur the image itself in an external application before loading it into Turtle.

Light Emission

Emit Light

Emit direct light from the environment by creating a number of virtual directional lights simulating the environment image. An alternative to this, which often is faster, is to use Final Gather instead so that the final gather rays extract light from the environment map.

Emit Diffuse

To remove diffuse lighting from IBL, disable this check box.

Emit Specular

To remove specular highlights from IBL, disable this check box.

Samples

Sets the number of virtual directional lights created if Emit Light is enabled. This will affect how soft the shadows will be, as well as the general lighting. A higher number of samples, gives better shadows and lighting but increases the render time.

Intensity

Set the intensity of the lighting.

Specular Boost

Further tweak the intensity by boosting the specular component.

Enable Shadows

To create shadows, use this checkbox (also dependent on Ray Tracing Shadows).

Banding Vs Noise

Control the appearance of the shadows, banded shadows look more aliased, but noisy shadows flicker more in animations.

Photon Emission

Emit Photons

Enables photon emission from the environment map.

Caustics Photons

Number of caustics photons to be emitted into the scene.

Global Photons

Number of global photons to be emitted into the scene.

Photon Energy

The total photon energy.

Related topics