A classic SF corridor

Hi people.
It’s a great classic: the SF corridor. Here maybe not so SF, but surely unusual and mysterious. Like some kind of prison. The presence of an open toilet area make it think « what is this place? » The small locker slightly opened with a red light inside, suggests that something is going wrong. The red color is cutting nice onto the green tiles wall.
It started with a simple test with only the wall with the bathroom sink, origin of the scene’s name. And then, why not continue with the rest?

Great thanks to Cynicat Pro who for his study of PBR (Physically Based Renderers) group nodes. I highly recommend watching these explanations, I learned a lot.

The final render is composited in photoshop. Layers: combined, AO, Emitter and mist. The mist helps alot to give the impression of the distance from the point of view to the far wall. Then many areas curve adjustments, like in digital photography.

Original render size: 4800 x 2700
Geometry: 315’570 faces, 60 lamps
Rendering time: 7 h 30 (CPU, iCore 3 GHz)

The large number of lamps is because I use 2 or 3 lights (with different parameters) for each light source. It helps to mimic reality that is always more complex that can predict Blender. I find that Blender is making a good global lightning but needs to be tweaked to feel more real.
I wonder if even with the big software renderers, the professionnals work hard to refine the result.

An early stage of the scene:

To show the importance of compositing to add depth and finetuning details:

Some material nodes.
This one for the dark grey metal frames along the corridor:

My custom ceramic tiles texture, based on the Brick Texture. I faced one big problem: the procedural texture generate perfect harsh mortar lines. When used for the bump mapping, it son’t give many shine borders between tile and mortar. We need some value here. A blur option will be great because without it we cannot make the tiles borders round.
But I found a workaround to smooth the bump:
Bake the Ambient Occlusion texture, open it in photoshop, blur edges and open it back in Blender. Works perfectly. I also correct the ground tiles in the far area.