As you can see, the original plate (top left) didn't make sense when the foreground car was added (top right). In several of the shots I had to reproject the background plates onto simple geometry, and crete a new camera with a new move (bottom left). Then when the same car plate is added it looks as if the car carries on straight down the road (bottom right).

Examples of some of the passes used for the cars (from top left to bottom right):
1. Original Plate
2. Reprojected texture on 3d car (stabilised)
3. Gradient (for removing studio reflections)
4. New reflections
5. Specular highlights and interactive lighting
6. Normals
7. ID mattes
8. Incadescence
9. Ground contact shadows

A quick comp to see how the passes work together

In some shots we either didn't have a background plate or they didn't match the car move. Above you can see the different layers that make up those shots (not final comp).