Glass Render-Settings
If you are experiencing long render times using glass surfaces, select the mesh and disable enable_internal_reflections in the Advanced section of the standard_surface shader.
Refraction Depth
Correct transmission_depth settings are important for achieving realistic glass and water effects. Bear in mind that higher values will increase render time.
By default, Arnold uses a transmission_depth of 8.
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| 2 | 4 | 8 (default) |
The scene below contains many glass surfaces. Increasing the transmission_depth reveals more detail in the refracted glass.
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| 2 | 4 | 6 |
Total Depth
When increasing ray depth settings, make sure that the total depth is set high enough to include the transmission_depth .
The total depth specifies the total maximum recursion depth of any ray in the scene (diffuse + transmission + specular < Total).
Final Render
Here is the final image. The transmission_depth has been left at the default value of 8. Higher values may be required to reduce further areas in the splashed water where the render appears solid black.
The scene file can be downloaded here.