In my scene, I applied a direct light with V-Ray shadows in certain areas to have some fuzziness in the shadows. I also colored the light and the shadows to have a pictorial result, not a photorealistic one (Fig.10).
I took the antialiasing "in catmul" and used the "linear workflow" of V-Ray, which allows you to have a more homogenous result. Then, I used the V-Ray pass rendering, which is indispensable for post-production. For the moment the 3D render was cold and impersonal, but allowed me to have a good perspective, volume, scale and direction of light (Fig.11).
Before I talk about going to Photoshop, let's look at the pass rendering (Fig.12):
1. Wire color: selection of each element to retouch the materials or the lighting independently
2. Raw shadow: work on the shadows separately
3. Depth: to obtain depth of the field or not
4. Reflection: working on the reflection of each element
The post-production stage was the part of this project I liked the most because it allowed me to really personalize the image. As I mentioned earlier, before the 3D rendering the image was too cold and impersonal (Fig.13). So I decided to destroy the too perfect part of the 3D with 2D work in Photoshop.
First I placed a sky in the background, in agreement with the concept art (Fig.14). Then I added some new elements to the image to break up the too perfect 3D rendering (Fig.15). I painted over the 3D to add a bit of dirt with the help of textures and brushes. A very practical tool to break up lines that are too straight is the Eraser.