"We wanted it to be like dealing with real world materials: aluminum, stainless steel, copper and bronze. So we tried to use car and engine parts. But the problem in CG was that we had to adjust shaders quite a bit because in putting the light on any one of those robots, all the different metals did not respond shot to shot. It required a lot of adjustments: once we'd get it for a daytime exterior with a key light coming from behind them, when you swung around to the other side it needed a whole new adjustment, where it's frontally lit. That was custom fit for every lighting scenario."

Color too posed a problem. Depending on the time of day, color temperatures altered a car's look. For example, Jazz, the gray car, could have different shades of gray. "You could find photo reference but this was somewhat of a moving target, which is what made it so difficult," Farrar insists. "We actually recorded every single camera position as far as reflective environments, plus we had the Macbeth color chart, and we had to abide by that very specifically, even though we could cheat too. So we started out with a lot of reference photography of each of the cars, and you will see beyond that in some of the close-ups, that we wanted to have the metal flake that's in the paint. This was all done in the computer and it has to exactly duplicate what's in the real world, including the clear coat and the several coats of finish that go in a paint job and specific reflection and refraction.

"We used every bit of ray tracing but it's also a tribute to our modelers and paint people because of the layers of bump and paint. Of course, as we moved forward, we started throwing the robots or cars in the shots. Optimus is a good example. There was a particular shot where suddenly his chest, which is comprised of the firewall and the cab windows and windshield wipers, is front and center. So Ron Woodall, who's our paint lead, would get called in for more detail like the molding, scratches and oil smears. He and his team would provide a bump map so we wouldn't have to change the model itself.

Eyes posed a problem and ILM had to put an improved internal tube with lighting inside to get a better read. Bumblebee was the litmus test since he was the most emotive robot. 

"Now we did have to go back in for the eyes, which were a problem. We had specific designs from Michael and the production design staff. Those were 2D and as soon as went into 3D, once we tried to get the animation moving, especially the eyes, I was not happy. We couldn't get the eyes to look on and off access. If you did little eye darts, you couldn't read something that might be a pupil. We're used to what eyes really look like, so we put an [improved] internal tube with lighting inside, so you could get a better read, and we also put in what I call Norelco blades, which is a circular thing that ratchets around, and can open and close -- it's 50 or so pieces. This was so you could get some emotion, not including the hundreds of cheek pieces and the rest of the metal bars around the eyes, that can help mimic a wink or a blink or a wince. Bumblebee was our litmus test. I knew what the materials were, and once he looked realistic to me and was emoting, even the tilt of the head, we hit something terrific."

Farrar credits the Creature development team with not only successfully chaining the characters but also coming up with a more nimble Ninja fighting style. "Scott Benza did months of testing -- MoCap, keyframe animation simply based on reference tapes that we made ourselves for motion study. We wanted a much more interesting look for fighting rather than the old stomping style."