Lighting is complicated, to say the very least. While there a numerous things that make lighting difficult, one of the most overwhelming aspects of lighting is just how many different tools there are. Without a practical knowledge of the various tools at your disposal and how to use them to sculpt light, your lighting can never reach its full potential. However, breaking the process down into small pieces and learning one tool at a time can make it far more manageable. Today, we'll look at one of the most underrated and under-utilized lighting tools, the flag.
Flags, also known as cutters, are pieces of thick black cloth, usually duvetyne, that are stretched over a metal frame. They are typically used to completely block light from falling onto a certain part of the frame, which is accomplished by manipulating the position of the flag in relation to the light by using a c-stand. Although flags have a staggering number of uses on a film set (courtesy flag, anyone?), there is one application that is absolutely crucial to effective cinema lighting: creating meaningful contrast within a scene.
Here's a video tutorial from Lights Film School, which also has a fantastic educational blog that's certainly worth perusing. In the video, they break down some of the best ways to use flags to increase contrast in your scene.
In this video, contrast is being added to the scene in two ways. First, one flag is being used to cut out light being cast onto the background by the key light, which is meant to light the actor. This is, by far, the most common use of flags on a set, although if you're short on flags or c-stands, barn doors can accomplish a similar effect (although I find flags to be the most versatile and effective method). The second way that contrast is being added to the scene is through flagging off just a small portion of the light on the actor's face, which creates a far more dramatic look than if the light was hitting him directly.
When using flags to block out light from a hard source, one of the most important things to consider is the distance between the light and the flag. If a flag is too far away from the source, it will create harsh, hard-edged shadows that will look unnatural and give away the placement of your sources. Unless you're going for an incredibly moody noir look, this is something that you should avoid. Instead, try to keep your flags within 8-ish feet of the source, so that the shadows from the edges of the flags are softer and less defined. This can create nice gradients of light that are extremely pleasing to the eye.
In addition to blocking out light directly from a source, flags have another wildly important use in film and video lighting, and that is to create negative fill.
Unlike the previous instance where flags were used to block direct light from falling onto a certain part of the scene, the process of using a negative fill is about subtracting ambient light in order to create contrast. Most often, negative fill is used in scenarios where natural light is in play. In these scenarios, it is often far easier and more convenient to subtract light from the scene than it is to add it. In order to control the amount of contrast that a negative fill provides, simply move the flag closer to the subject (for more contrast) or farther away.
Flags are an incredibly useful tool in the process of lighting for film and television, as they are one of the best ways to introduce thoughtful contrast into any scene. Through practicing and mastering the various flagging techniques discussed here, the effectiveness of your lighting will increase manifold.
What do you guys think about these flagging techniques? How have you used flags (or any light-blocking object) to better the lighting in your work? Let us know down in the comments!