I'm trying to create an effect of lightning rolling through storm clouds with a moon in the background. So my setup is the moon in the center and I've got a spotlight on it with a yellow fill. Next I've got a 2 groups of clouds, one on the left and one on the right. My challenge is to give a dim light on the clouds. and then have a another light move left to right against the clouds to give it the effect. My problem is controlling the light. Is there a way to isolate the light to each group without affecting the other? I was messing with the shading controls and that works with limits.