Ok, so you’re Greg Toland and Orson Welles on the set of Citizen Kane. You’ve got your characters and blocking set, your lens is mounted and the angle is just right. Now what? Well, hopefully you’ve shed a little light on your scene. Now, this isn’t a discount to the effectiveness of good color scheming, but at least in respect to creating visual depth in a scene, most if not all cinematographers would agree that their weapon of choice is light. The science also says that the human eye is more sensitive to variances in light or “luminance” than it is to changes in color or “chroma.” Let’s boil it down. If we treat lighting like a game, the objective here is separation. Separation between your subject or subjects, the foreground and the background. So maybe you light the background with more intensity than the foreground. Or maybe the reverse. What about some combination of the two? What about the same intensity? What’s being lit now? The separation also takes place on the subject. Creating variance in luminance can be as simple as casting a shadow. The “chiaroscuro,” or treatment of light and shade changes based on the placement of your light. And, when used in combination with the objective of separating foreground from background, this can yield some interesting, maybe even dramatic, results. Here’s an exercise: go back and watch Citizen Kane. With every shot that catches your eye, pause it and take a look around. Where’s this light coming from? How intensely is it falling here? And from there, you can start asking yourself, why? Why light it this way? What does it say about the character, about the story? Light is a tool. Just like your tripod, just like your camera, just like your lens. But if watching Gregg Toland and Orson Welles work on Citizen Kane has taught us anything, it’s that maybe the lack of light is a tool just as powerful as its presence.