• Uses Ambient Occlusion (AO) to mimic a part of Global Illumination (GI)
  • Control over Diffuse and Tracing depth
  • Fastest Interactive Engine.
  • CPU + GPU
  • Used in both Production & Interactive Mode.
  • In many cases, it can be used for convincing final renders.


  • Supersampling: Improves antialiasing of the rendered image at the expense of increased memory.
    None: No Supersampling, Normal: 2×2, High: 3×3 and Auto: none for Interactive, 2×2 for Production
  • Tracing Depth: Controls the tracing depth of Reflective & Refractive surfaces.
  • Diffuse Depth: Sets the number of light bounces on Diffuse surfaces.
  • Extended Tracing: Extra tracing depth for Transparent & Translucent surfaces.
    Values defined here will be added to the Tracing Depth value.
    Total Tracing Depth = Tracing Depth + Extended Tracing.
  • Motion Blur: Globally enables/disables Motion Blur.
  • Displacement: Globally enables/disables Displacement for all the materials having Displacement active.
  • Relight: When on, the user can control each light separately during and after the rendering has finished.

Clay Render

All materials in the scene will be rendered as diffuse gray with respect to bump and transparency.

  • Reflectance (%): Increases/Decreases materials reflectance (from black to white)


Termination criteria are being used to stop the engine after a specific amount of time or samples.

  • Time Limit: Specifies the render time.
  • Sample Limit: Specifies the maximum number of samples.


  • Threads: Number of threads to be used while rendering.
  • Seed: Specifies the initial number for the random number generator engine. It is best to leave the default value (auto) and let the engine decide.
  • Priority: It is best to leave this to the default value (low). Low Priority does not mean low performance but is generally stable.
  • Network: NoneServer: Current machine + all network nodes, Pure Server: only network nodes
  • Server Port: Should be left at the default value, except if there is any other application utilizing the select port number.
  • Bucket Rendering: Helpful for high-resolution images with additional render layers when rendering with GPUs.


A list of all the Cuda-enabled GPUs will be populated in this place, allowing you to enable or disable them one by one.

  • Device Mask: Select between GPU + CPU, GPU only, CPU only.
  • CPU Threads: Controls the CPU logical core allocation for Enhanced Thea Presto performance in both Production and Interactive rendering.
    • Auto: Automatically handled by Presto.
    • Max (-1) (-2): Removes 1 or 2 logical cores.
    • Max GPUs (-1) (-2): Removes the total number of GPUs from the total number of logical cores. -1 and -2 will remove additional logical cores.
    • 1…x: Manual logical cores selection. This section is populated based on the type of CPU.


  • Use Extended Tracing in scenes with Dielectric materials instead of increasing Tracing Depth. High Tracing Depth values will increase render time significantly.
  • Some times you can create final renders just by using Ambient Occlusion (AO). If needed, start increasing Diffuse Depth to have some light bouncing in the scene.



Diffuse Depth controls the number of bounces of a light ray on diffuse surfaces. A value of 0 means that the scene will be illuminated only by direct lighting.

Black areas behind transparent surfaces can only be solved by increasing Tracing Depth or by enabling Extended Tracing. Increasing Diffuse Depth will not help in this situation.