The shaders were quite simple: lots of fresnel effect for the glass and metal and then simple shader trees layered with a mib_color_mix node (Fig.03c).
Fig: 03c
Lighting & Rendering
At the beginning I wanted to try the new Mental Ray pass system, but after a while I liked the raw render from Maya so I decided just to use a beauty pass, an occlusion pass, and one pass for light fog, as well as some masks. I ended up with 16 passes (Fig.4a), mostly masks, because I wanted to be able to do separate color correction while still producing an image ready for animation without hand-drawn masks or retouching in Photoshop.
Fig: 04a
Lighting was really fun but also time consuming... I think I spent most of my time on this and on compositing. I rendered a lot of different versions with different colors and light rigs (Fig.04b) going back and forth between versions until we found a good combination of mood and details.
Fig: 04b
I used a technique I saw in a DVD from Jeremy Vickery (
www.jermilex.com) on the use of Ambient Occlusion to simulate bounce/fill lighting. All you have to do is to connect the output of the AO to the ambient color of all the shaders in the scene (Fig.04c). You have to think about it like this: the light color is going to light the non-occluded parts, while the dark one is going to light the occluded ones, so avoid pure black and pure white! I also put some orangish tones in to warm the image up.
Fig: 04c
After establishing the key + fill I started adding bounce lights for the sunLight and a lot of rim light to separate the objects from the background. This is a screenshot of the scene and a list of all the lights in the scene (fig. 04d). I also added some reflectors with a white surface shader to give that cartoony look to the reflections on the glasses.