Arnold core features
Arnold GPU supports a set number of Arnold features, including arbitrary shading networks, SSS, hair, atmospherics, instancing, and procedurals. See here for a detailed list of Arnold GPU features and known limitations.
C4DtoA features and known limitations
Arnold Object Mask tag is not supported
Arnold Custom AOV tag is not supported
- Light linking (Include/Exclude objects on the Project tab) is not supported
- C4DtoA specific shaders from previous versions (prior 2.5.0) are not supported (e.g. when loaded from a previously exported ASS file via an Arnold Procedural):
- mesh_light_material (visible mesh light)
- c4d_vertex_map (Vertex Map)
Recommended NVIDIA drivers:
The very first time you render with the GPU, the GPU renderer has to create a cache of shaders. This can delay the time to the first pixel for your first render.
To avoid the one-time delay, we recommend that you run Pre-Populate GPU Cache before you do any renders. Note that pre-populating the cache can take up to 15 minutes.
The cache only needs to be re-populated after installing a new Arnold version, updating to a new NVIDIA driver, or changing the hardware configuration of GPUs on the system.
Selecting a Render device
You can easily switch between CPU and GPU with a single click in the System render settings.
Matching Noise on CPU and GPU
Matching noise can take a little experimentation because Arnold GPU uses Camera (AA) sampling only. We recommend you also use Adaptive sampling. Here are some guidelines:
- Set the Max. Camera (AA) in the range of 30 to 50 (depending on the scene, you might go closer to 100). In general, the max samples should be a large value. A large max samples means that the quality is controlled by the noise falling under the threshold, instead of by clamping to the max AA.
- Set the Adaptive Threshold to something like 0.015 or 0.02. For a noise-free render, lower the threshold value, maybe even as far as 0.010.
- Set the Camera (AA) samples to around 3 or 4. One of the few reasons to go higher with AA is for motion blur. The higher the number of Camera (AA) samples, the less of a speedup you'll get from adaptive sampling.
All textures must fit in memory. We recommend you use tiled and mip-mapped TX textures. If you're running out of memory, you can set a maximum resolution for textures in the Render Settings.