Lighting the dungeon was kind of complex. I used 22 lights (some of them, instanced). For the outside, since it's a night scene, I used a dark blue for the environment and a light blue Direct light for the moonlight (it's a common mistake to think there's no light at all at night). In order to see a silhouette of somebody walking by outside, I placed a streetlamp with a Spot light and volumetrics on (Fig.14).
On the inside, the main light source is the halogens on the ceiling, which are Photometric lights, using the well-known IES file "1589835-nice". Some other lights are: another Photometric light on the stairs, with a warm orange tint, a huge VRaylight coming from behind the camera, and both lamps (the Tolomeo on the left and the right-hand corner one). And the rest of the lights in the scene are the ones that come from the screen of the monitors and the LEDs of the Tsunami cases (VRaylights for the most part) (Fig.15).
Something important I should say: I used a VRay Physical Camera and so all the light multipliers shown in Fig.16 depend on this special camera. Here you have the camera and V-Ray render settings (Fig.16 - 19).
On this occasion, in addition to the render, I generated an Ambient Occlusion pass (AO). To do so, I used a VRayLightMaterial, with a mix map (black and white), and VRayDirt as the mask. There is a nice tutorial about this on the blog of the great master (and my friend) Juan Siquier: http://siquier.blogspot.com/2006/08/aaoo-pass-con-vray-15-rc2.html
I used Eyeon Fusion for post-production. I'm quite new at using it, but the more I use it, the more I like it. It's highly intuitive and you have a great level of control over every filter through the tree-node. So I imported both passes (Diffuse & AO), merged them, played a little with the opacity, and added some color correction, brightness and contrast, a slight chromatic aberration and vignetting (Fig.20).
Well, that's all. I want to thank everybody that has somehow helped me throughout the process (especially Alejandro Suárez "Jan", Javier Núñez "Ja3D", Jorge Amigo "Joalamber", David Bastidas "Kh0rne", Juan Siquier, Alejandro Martín "R|P", and everyone at #3DInfografica on IRC Hispano). And of course, thank you all for reading this Making Of. I hope you've enjoyed it and found it helpful. Best regards (Fig.21).