In Photoshop, I tend to work with colors, shading, and lighting each on their own layer. While working on the highlight and shading layers, I turned the base colors invisible so I could see better. This is what it looked like.
I thought it was kind of cool, so I figured I'd share. Maybe it'll be, I dunno, informative for somebody or something.
What happens if, instead of it being empty, you darkened everything so it was practically pitch black with this as the only light? Slap up a dark blue layer between the colors and the light and burn it to the colors below?