You can also use a Phong node instead of a Specular node to drive the gradient. The difference is that Phong calculation is strongest when the surface points at the light, whereas the Specular calculation is strongest when the surface, if it would be a mirror, would mirror-reflect the light into the camera.

Phong is on the left, Specular is on the right.

Probably the Phong type is more correct, but either works in general. Whatever you have in C4D - if you can use it to drive the diffuse color gradient, do it.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)