Step 10/14 - Scene settings
I used actually a Vray Sun plus HDR image as a background + A cylindrical Scene Background image. I placed Skyportals in all openings, minding to set subdivisions to 32 to avoid noise. Also the Sun size is a bit larger (2 or 3) to have smoother shadows, and its shadows subdvis are also 32.
The scene took 8 hours to render and was 1400 x 2000 px. I allowed such a long time only because it was a personal project, otherwise I would have set everything differently. My machine is a Quadcore with 16 GB of Ram, and a i7 – 2600 Processor , 3.40 GHz of second generation, 64 bit system. Irradiance map was set min -4 and max -4.
In the following image you can see VfR option parameters.