Been fooling around with compositing renders onto real photos:

I'm almost there with this one, but the shadows aren't quite right- faint shadows actually show up brighter than the road. To build the render layer, you lay down a plane under the cars that accepts shadows and creates an alpha channel, then you use the alpha mask to lay it on top of your background photo. I think all I need to do is change the color of the plane to match the r   [... read in full]