Unity recently added support for Path Tracing using Octane so I decided to give it a try. I was in the beta program for a few months and it turned out the A320 CAD model in Unity caused quite a few problems due to the large amount of materials used. But eventually it did work.
Here is a sample render. Right click->View Image to expand. (WordPress really has to make this easier)
Although it works pretty much out of the box, I discovered a few issues:
-All materials appear slightly more rough when rendered with Octane. Unfortunately there is no global slider available to fix this issue.
-The render buffer appears to be pretty low bit depth, causing white highlights to be over saturated or the entire scene looking too dark. It is not exactly HDR as you would expect. This is a common issue with renderers and is described in detail here. This could be easily fixed by Otoy but unfortunately this is yet to be addressed. You can work around this problem by saving the render as an 16 bit EXR and then modifying it in Photoshop but that solution is less than ideal.
-Currently there are a few bugs which require some workarounds. This includes GameObjects with disabled MeshRenderers still being rendered and spot lights casting shadows.
-A model designed for realtime rendering does not necessarily look good with Path Tracing. This is not the fault of the Path Tracer but due to the fact that flat geometry with detail in AO maps is not rendered. Have a look at the screws on the FCU and you can see that it lacks AO. I did not try enabling the AO maps (not sure if that is possible) but that would make other geometry look worse due to quality issues. My AO mapse are just not designed for close up renders.
Even with the current issues, it is still an easy and quick way to get a nice looking render. And it is free 🙂