Chapter 12
Lighting and Exposure—Beyond the Basics
In this chapter, we explore lighting and exposure more deeply. We will look at concrete strategies cinematographers use to light a variety of common documentary situations, as well as aesthetic factors that filmmakers consider and some of the technical challenges that cinematographers face while trying to achieve a specific look.
When you first start out, movie lighting can seem somewhat mysterious and tremendously time-consuming. Once you have learned to control your image through lighting and exposure though, countless expressive possibilities become available to you. And the more you work, the greater your technical and aesthetic repertoire.
Basic lighting setups represent the building blocks of the cinematographer’s craft. Knowing these fundamental setups, which combine directionality, quality of light, and function, will help you to understand how to create certain visual effects and also help you determine an answer to the most basic question: Where do I put this light?
Once in a particular location, one of the first things to consider is directionality. Where is the light coming from? And where do you want it to appear to be coming from? Even when you are simply shooting an interview on the street, with no artificial lights, you can control the light by positioning the interview subject to face one way or another so the sunlight falls on them in a specific way.
It is always helpful to remember that the range of light placement options is three-dimensional. You can place your lights anywhere in the imaginary globe that surrounds your subject: in front, behind, along the side, high above, below, near, far—at any angle and any distance, as long as the lights stay out of the frame of the shot (although this, too, is not an absolute rule). Here are a few basic lighting angles, with an indication of the resulting effect created by each one. Remember, don’t just look at the direction of the light but at the throw of shadows as well (Figure 12.1).
■ Figure 12.1 The placement of lighting units determines the angle of illumination and the angle at which shadows fall. Pictured are five standard angles along the same horizontal plane: frontal (A), 3/4 front (B), side (C), 3/4 back (D), and back (rim light) (E).
- Frontal light is illumination that comes essentially from the angle of the camera. Because the light rays duplicate the camera’s angle of vision, most of the shadows are not visible to the lens as they fall straight back. Frontal light has a flat look resulting from this absence of shadows.
- Move the light along an arc, away from the camera, and shadows start to appear and become more prominent as the light moves farther from the camera position. A 3/4 frontal light is a lighting unit that is positioned at 45° from the camera. Notice the shadows cast by this light. This light position is often raised vertically by 45° as well. The presence of some shadows that create facial modeling makes this a useful light position for interviews.
- Move this light another 45° away from the camera so that it is now positioned at a 90° angle from the camera and we have a sidelight. This light comes directly from the side of the subject and has the effect of dividing the illuminated object in half, with one side lit and the other in shadows. Sidelight maximizes shadows and therefore texture as well.
- Moving this light another 45° away from the camera, we have a 3/4 backlight. The area that this position lights is mostly hidden from the camera, but we do see bright highlights on the top and side edges of the subject. Notice how this angle causes the light to illuminate the shoulder and hair, and cuts the light side of the figure out from the background while allowing the other side to blend into the shadows. This placement for a backlight is so common that it even has its own nickname, a kicker. This light is also commonly raised vertically by 45° to catch slightly more of the hair and shoulders.
- Finally, move this light another 45° from the camera and the light is now 180° across from the camera, illuminating the subject’s back. The camera can see only a small sliver of illumination around the top of our subject, as the front falls completely into shadow. This light is commonly called a rim light, and must be placed carefully to avoid flaring the lens.
In addition to the horizontal angles, you need to consider the dramatic changes in shadow and mood as you adjust the lighting unit’s height (or vertical angle) from high angle to low angle (Figure 12.2).
■ Figure 12.2 The vertical angle of a lighting unit can dramatically change the look of a subject. Pictured are a high-angle frontal (left) and a low-angle frontal (right).
Let’s look at a few basic setups documentarians commonly face, and at some strategies they use for lighting them.
■ Lighting Interviews
One area in documentary where lighting plays a large role is the interview. The documentary interview can take many forms from highly formal to “off the cuff,” in locations from a bedroom to a studio with a full lighting grid. Most approaches use some aspect of a strategy known as three-point lighting.
Three-Point Lighting
While the term three-point lighting refers to a specific lighting setup commonly used in interviews, in a more general way it is a good guide to the role different lights can play in any lighting situation. In any three-point lighting setup, the key light provides main illumination of the scene, the fill light takes care of shadows, and the backlight will help separate the subject from the background. The function of the lights is more significant than their specific placement. Sometimes two of the three will create the lighting effect you want, and at other times available light from, for example, a window can take on one of the three roles. Three-point lighting in its classic form employs a key light (positioned at 30° to 45° from the camera and at a 45° vertical angle), a fill light (usually opposite the key), and a backlight (usually a 3/4 back) (Figure 12.3).
While it’s a useful formula, it is important not to think of three-point lighting as a rule that must be observed in every shot, and it’s especially problematic to think that one should always light people with the three-point lighting scheme. It is useful, however, to understand how each of these lights functions in more detail.
■ Figure 12.3 A typical three-point lighting setup consists of a key light, a fill light, and a backlight. On the bottom you can see the effect of each light in isolation.
Key Light
The key light is the primary source of illumination in your scene (Figure 12.3, bottom left). Often the key light is a hard and bright light source, but it’s not uncommon in documentary to see soft keys, where the gentler shadows are kinder to the human face. The job of the key light is a base illumination, and to create depth by casting shadows (known as modeling). For formal “sit-down” interviews that look more constructed, the audience will not expect realistic lighting quality or placement. For scenes in which a more realistic look is needed, for example an observational scene where the interview is more impromptu, the key light should be a motivated light source, which means that when positioning this light you should consider the logical “real” source within the scene for that illumination. It might be that you actually use the sun streaming in through a window for your key light, or you might place a light to simulate the sun streaming in from the window in a naturalistic way.
Fill Light
As you can see in the directionality examples (Figure 12.1), a hard light (like most key lights) casts sharp and dark shadows. When lighting people, a hard key light will create nose and chin shadows and sunken eyes. A fill light is a soft light that is positioned to fill in some, but not all of, the shadows created by the key light (Figure 12.3, bottom middle image). Using a fill light is not mandatory, but it is commonly used in most lighting setups. Often in documentary interviews, the fill light is provided by a reflector bouncing the light from the key back onto the subject (Figure 12.4).
Typically the fill light should be placed at an opposite angle to the key light, which makes sense, given that it has to fill in the shadows that fall exactly opposite the illuminated area.
The degree to which you decide to fill in those shadows varies depending on the look you are after. You can choose to keep shadows quite dark, but fill in just enough to see some detail in the shadows, or you could almost completely fill the shadows with soft illumination, flattening out the image to create a bright image in which almost everything is visible. The critical factor in determining the density of the shadows is the intensity of the fill light. The stronger the fill light, the less prominent the shadows will be.
■ Figure 12.4 This interview uses a softbox light (a Chimera) as a key, a reflector for the fill, and a small Lowel Pro as a backlight. The result is a softer look than in Figure 12.3.
Backlight
A backlight is a light that separates the subject from the background by positioning a somewhat lower intensity light at a high angle behind the subject (Figure 12.3, bottom right). The backlight can be either hard or soft. It creates, along the edge of the subject, a rim of light that clearly traces the edges of the figure and helps create depth in the frame. When lighting people, this light is often a 3/4 backlight (or kicker), positioned opposite the key, which illuminates the hair and shoulders of the subject. Obviously the color of the subject’s hair is a factor in determining the intensity of the backlight. Blonde hair tends to thin out and create a halo when intense backlights are used. Dark hair or clothing against a dark background will benefit from being backlit. Backlight is so common in interviews that viewers expect it, and may even find shots without the separation from the background a backlight provides dull or hard to read. On the other hand, overly intense backlight that seems to come from nowhere can give your shot a highly artificial feeling.
There are many variations on three-point lighting. Figure 12.4 shows a setup where a softbox is used for the key light and a reflector provides the fill.
■ Lighting Styles
Looking at sample documentary interviews reveals that even within a three-point lighting strategy, there are ways to create very different effects (Figure 12.5). Consider the interview below, from Ken Burns’ film The War (2007). Cinematographer Buddy Squires has created a very stylized look, meaning that the image has carefully modulated areas of light and dark intended to create a dramatic feel. A counter example would be the interview in Ross McElwee’s Sherman’s March: A Meditation on the Possibility of Romantic Love in the South during an Era of Nuclear Weapons Proliferation (1986). This interview is more naturalistic, meaning that it appears less intentionally constructed, as though the filmmaker just happened to show up and no special effort was made to light the character. It is important to note that a naturalistic look does not mean that the subject has not been lit. The use of strictly available light does not always translate into what the human eye “naturally” sees, because no digital sensor sees light quite the way the human eye does. So in an effort to duplicate what an audience expects to see naturally, films employ considerable and careful technique in lighting.
■ Figure 12.5 Stylized and naturalistic lighting. On the left, Billy Squires created a mood of somber significance for an epic historical documentary, The War. On the right is a more naturalistic approach in Sherman’s March that conveys a feeling of spontaneity.
In the world of documentary, where the relationship with the real world is central, one might imagine that more naturalistic or realistic approaches to lighting would prevail. This is true, by and large, but there are many exceptions. The documentary interview, as suggested above, is often highly stylized. But you must always keep in mind that there are not two strictly delineated approaches or polar opposites—in fact, naturalistic and stylized lighting designs exist along a highly flexible continuum of aesthetic possibilities, and these approaches are often also mixed within the same documentary. That said, for our introduction, we’ll discuss the unique principles of each lighting philosophy in discrete terms.
Lighting Ratios
Through lighting control, we can easily create an image with relatively few shadows, or one in which shadows dominate the composition. These communicate very differently to an audience. Broadly speaking, prominent shadows tend to create a more dramatic mood. A look with fewer shadows feels more realistic than stylized, and speaks to a world where information can be readily conveyed. Lighting ratios (also called key-to-fill ratios) are the way you measure the relative intensities of the major light sources illuminating your subject: the key light and the fill light. The ratio between the key and the fill lights is expressed as key + fill : fill. If you are a cinematographer, you will probably have a light meter, and can measure the key-to-fill ratio in foot-candles (p. 191). If you don’t have a light meter, you can zoom in to a specific area of the frame and use the auto-iris control on your camera to get a reading for the isolated key (on the brightest side of their face) and the isolated fill (the other side). The key here is relative readings. If you get an f5.6 from the key side, and an f4 from the fill side, you know the ratio is 2:1 (remember, every setting in the f-stop scale doubles or halves the amount of light entering the lens). A lighting setup with a low key-to-fill ratio, like 2:1 or 3:1, means that the fill light is filling in shadows until they are quite light. A ratio of 1:1 means that both the key and the fill are the same intensity and there are no shadows at all.
A lighting setup with a low key-to-fill ratio overall, not just on the face of a subject, is called (somewhat confusingly) high-key lighting (see Figure 12.15 for an example). High-key lighting ensures visibility in all parts of your scene with an overall bright and even illumination. High-key lighting minimizes shadows, texture, and dimensionality. Conversely, a high lighting ratio like 16:1 (4 f-stops) will yield very dark and prominent shadow areas. This occurs when the intensity of the fill light is considerably lower than the key. A lighting setup with a high key-to-fill ratio is called low-key lighting. In the Buddy Squires interview (Figure 12.5), a low-key effect is achieved by creating alternating vertical bands of light and dark. The left side of the subject’s head disappears into shadow, while the other side is framed by a dark patch as well. A practical and a window on the right add another band of light.
■ Exposure Control and Metering Light
Digital cameras all use some form of through the lens (TTL) metering to figure out what the correct exposure should be for a shot. A TTL meter is a reflective light meter that calculates the exposure by averaging out the light from a scene after it has entered the lens. A reflective meter measures light bouncing off of a surface, as opposed to an incident meter, which can read light falling directly on a source. A reflective reading is taken at the object you’re lighting rather than in the camera. Exposure is actually a combination of the light reflecting off the scene, the sensitivity of the sensor (or gain, which can be varied; Chapter 8), and the f-stop, which is also variable (Chapter 9). It is important that you know how your particular camera “reads” the scene to figure out the exposure. Often cameras use center-averaging, basing exposure on light values at the center of the image. This is fine if you want to expose for the center of the frame, otherwise it’s problematic. In other cases, a camera will weigh the light values across the scene and give you an average. This is also a problem. Imagine a room with a window. If the camera exposes for the bright sunlight outside, your scene inside will be shrouded in darkness. Conversely, if someone is in front of a very dark background, like a curtain or a blackboard, the camera may overexpose them.
The first thing you must do to take control of exposure is find out how to turn off the automatic iris function. Look for the manual aperture override (also called “manual exposure”) function on your camera and turn it off. Second, you need to know how to tell what the f-stop setting is at any given time. Only some high-end professional cameras actually have the f-stop scale etched on the iris ring. Many cameras, if you turn the auto-iris function off, display an f-stop scale on their LCD screen or viewfinder. Typically, you will see an f-stop displayed in the viewfinder. Consumer cameras often have no scale at all, requiring you to judge exposure by eye.
Manual Exposure Control
Determining your “best” exposure requires using a combination of the zoom lens, the in-camera meter, the automatic iris, and the manual override functions (Figure 9.23).
Here are the standard steps for finding the best exposure for your shot:
- Decide which part of the frame you would like exposed correctly. This is an aesthetic decision based on the composition, mood, and story.
- With the camera on auto-iris, zoom in tightly to that portion of the composition, preferably so that it fills the frame, and let the auto-iris select the “correct” exposure for that small portion of the total scene.
- Turn off the auto-iris by switching to manual override. This will lock in that exposure.
- Zoom out and compose your shot. It doesn’t matter where in the frame you place your subject, or how bright the background is, or what might pass in front of the lens during the take. Your exposure is locked in and will not change.
- Finally, tweak the manual iris to finesse the exposure by looking at the final result in your viewfinder or on a high-quality field monitor.
Keep in mind that you can zoom in to any portion of the scene and lock in the exposure there to check out the effect of various apertures. This will give you a clear sense of the exposure possibilities for your scene.
Sometimes you will want to use a light meter to augment the camera’s internal metering. This can be particularly useful when setting up the lighting for an interview, where the relative light values should be important to you. If you want a specific key-to-fill ratio, for example, you can measure the value of your key light in foot-candles and then talk to your cameraperson about what they need to do to give you, say, a 4:1 key-to-fill ratio without having to keep the cameraperson busy zooming in on the left and right sides of someone’s face. You know that a reading of 200 foot-candles from the key dictates a reading of 50 foot-candles from the fill side. By the same token, if you are trying to create a lighting setup for an observational shoot where you may need to evaluate the light throughout a whole house, or a school building, a light meter can give you a sense of some of the things you may need to do to control exposure, whether lowering the blinds on a window or turning on overhead lights, and so on.
The Incident Light Meter
The incident light meter is the most common and versatile meter used in media production (Figure 12.6). It measures the intensity of light falling on a particular part of a scene. This meter is simple to use and gives a consistent reading from shot to shot. All incident meters have a half-globe light diffuser, called a photosphere (or “lumisphere”), which fits over the photosensitive cell. The photosphere, held near the subject and pointed toward the camera, gathers the light falling on the subject from the front and sides, and averages out these light intensities to arrive at an overall incident light intensity reading.
The actual measurement taken by a meter is in foot-candles in the United States, or lumens in the metric world. The meter takes that number, along with ISO information and shutter speed, and calculates an appropriate exposure. One of the problems with using a meter to derive an actual f-stop is that most video cameras don’t use the ISO system to define their light sensitivity (remember they use gain instead). So you need to figure out what the ISO equivalent is of, say, 0 dB or +3 dB gain. DSLRs use ISO numbers, and hybrid cameras like the Canon C100/300 series can be set to use either gain or ISO numbers, making accurate external metering easier.
Another aspect of newer cameras is their ability to shoot in an extended dynamic range or log gamma mode (p. 203). The added dynamic range means extra f-stops and added picture information, which is great. It also means that for the first time with video cameras, what you see in the viewfinder is NOT necessarily what you get. The image you see when shooting in an extended dynamic range or log gamma mode will often look washed out. In these cases, using a light meter to check light values may offer you reassurance that the ultimate results are going to be what you want (Figure 12.18).
■ Figure 12.6 This Sekonic L-308DC light meter is designed for use with video cameras, and gives accurate readings to small portions of an f-stop.
The Gray Scale
One other useful tool for controlling exposure is the gray scale. The gray scale is a chart calibrated in steps from black to white (Figure 12.7). Each step halves and doubles light in a way that corresponds with a camera’s f-stops. These different steps are often called “zones” based on the work of American photographer Minor White.
The most important zone for us to consider, in order to understand how light meters work, is the one right smack in the middle, between pure black and pure white. Zone V has a reflectance value of 18 percent and is also known simply as “middle gray.” All light meters, incident or reflected, are calibrated to the middle gray tone. In other words, they tell you what kind of exposure they think you need, to make sure that a middle gray in a scene will give you a middle gray in the reproduced image. Of course, it is up to you what you want to do with that information. As we suggest, this is only a place to start from. In fact, if you take a picture of either a gray scale or an 18 percent gray card using the camera settings you are using to expose your scene, it will give you a way to cross-check your exposures later. If you are doing serious lighting or shooting with an extended dynamic range, you will also probably want a chip chart, which gives you a reference set of light and color values. Filming the chart will create a record of your exposure and color settings that can be used to calibrate the color grading in postproduction (Chapter 22).
■ Figure 12.7 Minor White’s Zone System uses a gray scale divided into eleven steps, or “zones,” which can be used to assign an exposure to a subject according to predetermined reflectance values.1
■ Lighting Observational Scenes
A political convention, a meeting at a school, a busy household. As we discussed in Chapter 2, much documentary filmmaking is observational. People are doing something and you are filming them. When you approach lighting for an observational scene, the first thing you need to ask yourself is what is important in the scene. What do you need people to be able to see? Then, what kind of feel are you going for? While the goal of reaching the basic exposure levels needed to film in a particular location may be easy, it is how you light your scene that will define your approach to filmmaking. A key factor is how aware your viewers are of your lighting efforts. A light that appears to come from a natural source such as the sun, or an overhead light in a room, is called motivated. Motivated lighting gives a realistic effect. What reality actually consists of is a question for philosophers, but for filmmakers it’s important to remember that realism is a style, one that you may have to work to achieve. For most observational filmmaking, an approach that does not call attention to itself, but serves the larger goal of presenting us with a look at a real situation, will prevail. Another name for this approach is naturalism, literally “making things look natural.”
A naturalistic approach strives to appear as plausible and harmonious with the real environment as possible. Lighting direction and sources are always motivated, lighting continuity is observed from shot to shot, and the relationship between the various light sources duplicates what we would expect in a real-life situation. For this reason, the impact of naturalistic lighting is subtle, unobtrusive, and realistic. Obviously, one way to obtain a raw, naturalistic look is to use no artificial lighting but, rather, to use only available light.
The direct cinema and cinéma vérité films of the 1960s, which used new high-speed film stocks such as Tri-X and 4-X, allowed shooters to follow subjects pretty much anywhere without adding light (Figure 12.8).
Naturalistic lighting, however, does not necessarily mean that a filmmaker uses only available light. Documentary filmmaking offers an endless variety of shooting situations and many of them are interior spaces not designed with filmmaking in mind. Often filmmakers will bounce a hard light off a ceiling, or hang a paper lantern or two from the ceiling, to raise the light levels of a space in general. While you will develop your own approach, there are a few things to think of. If you have to light a large room with many occupants very quickly, say to film a public meeting where you don’t have control over who moves where, the easiest thing to do may be to bounce a hard light or two off the ceiling (especially if the ceiling color is light). Another approach is to do some kind of 180° lighting, with lights at two ends or sides of the space. This kind of cross lighting means both lights act as key or fill (or front light and backlight), depending on which light your subject is closer to. You will also get modeling on your subjects in a way that will help separate them from the background.
■ Figure 12.8 With images like these from Don’t Look Back (1967), D.A. Pennebaker redefined documentary naturalism. In the medium shot on the left, Dylan’s torso disappears into the background, while in the group shot on the right, the available light is all on the background, leaving Bob Dylan, Donovan, and their pals in the murk. Every shot is a claim of authenticity that cries out, “We didn’t manipulate the lighting here!”
Lighting an observational situation, like a house that people will be walking around in unpredictably, calls for another strategy. A few lights placed in strategic locations, perhaps the kitchen where people tend to gather, or hung on bookshelves and in doorways, may give you enough light while keeping your lighting instruments off-screen. The trick here is to avoid having light stands that might appear behind a subject at an inopportune moment. Clamps and hangers, to keep lights off the floor, are essential. Sometimes a light on a fire escape, or in the yard pointed in through a window to simulate daylight, can also be helpful.
Today, with highly sensitive imaging devices that can offer a very broad range of exposures, a naturalistic strategy that uses only available light is also quite possible. As filmmaker and cinematographer S. Leo Chiang says,
I don’t like using what feels like artificial light in an observational situation. And also, this camera (the Canon C100) does so well in low light that I don’t find myself needing to add light. With my previous camera, sometimes I would go into a room and put up a couple of paper lanterns, china balls, just to bring the ambience of the room up. But now I try not to use anything additional if I don’t have to.
For indoor situations during the day, I always try to move the subjects out of the spot in front of the window, so I can be in front of the window and they won’t be backlit. I have this weird technique. I don’t ask people to move, but if someone is standing somewhere I don’t want them to be, I will actually go next to them, pretending I’m shooting, and they will move away from me.2
in practice
■ Dealing with Windows
One of the most common issues you will face, especially if you are working with available light, is windows. The problem, as you can see in Figure 12.9 (left), is the high contrast ratio between the bright scene outside the window and the face of a subject inside the room. While you could spend time putting artificial light on the subject, or putting ND gels on the window, a quick solution is to simply move the subject away from the window, as in Figure 12.9 (right). This allows you to take advantage of the light from outside, as opposed to fighting it.
■ Figure 12.9 If a subject is standing in front of a window (left), it is wise to move them so that the cameraperson has his back to the window and the subject is facing him (right).
■ Set Lights, Specials, and Practicals
There are several specialized lights used for lighting interiors, and like other lights we have discussed they are described by their function. Set lights are used to light the larger areas of the set: the architecture, furniture, set dressing, and so on. In interview setups, a set light is often used to illuminate part of the background behind the subject.
Specials are low-wattage, unobtrusive lights used to “kick up” the illumination on a specific object or a small area of the frame. For interviews, one of the most common types of specials is an eye light, a very small light carefully narrowed by barn doors to just put a bit of sparkle into the eyes of a subject.
Lights that are part of your location, such as household lamps and overhead fixtures, are called practicals. In some cases, they can provide useful illumination, but often they are not powerful or controllable enough for a good exposure. At other times, they may be too bright for what you want them to do. A common practice in documentary is to rebulb such lights (with either higher or lower wattages) so they work better in the scene, or to put them on dimmers.
■ Stylized Lighting
Stylized (or expressionistic) lighting approaches are designed to draw attention to the aesthetic components of the image. Lighting placement, color, and exposure can be unmotivated, or motivated by a logic other than the plausible illumination of the particular physical environment. For example, a stylized lighting scheme might be motivated by the dramatic logic of a scene, by character psychology and point of view, or by the need to create a specific emotional tone or additional thematic layer. Stylized lighting is often associated with nonrealistic film genres, like fantasy films, or films that intentionally invoke an overtly theatrical tone. At first glance, this might seem to put stylized approaches firmly outside of the world of documentary. But documentary is not one thing. In Isaac Julien’s Frantz Fanon: Black Skin, White Mask (1996), about the psychiatrist and postcolonial theorist Frantz Fanon, the filmmaker uses highly expressive lighting for dramatic effect (Figure 12.11). The low-key look, with its many shadows, emphasizes all that is unknown in the human psyche. In more dramatized tableau sequences, light is used to separate and emphasize various parts of the scene. There is much use of cookies to create a “prison” effect of projected bars on the actors in these reenacted sequences.
in practice
■ Lighting for Observational Shooting
In Casting the First Stone (1991), a documentary about women on both sides of the “abortion wars,” Julie Gustafson worked in her typical highly observational style, an approach that means spending large amounts of time with her subjects over days, weeks, and months. Outdoors she depended on available light, and the fact that she would film in the same situations several times (Figure 12.10). She also makes a point of arriving ready for anything, with her camera and sound gear already rigged to roll. She carries a light with her, typically a Lowel Omni, in a small backpack with its own stand and extension. This means she is literally “ready for anything” whether an exterior or a trip to a dimly lit diner or office. For interiors where she will be returning more than once, such as the home of a subject, she uses a naturalistic lighting strategy. This doesn’t mean foregoing lights, however. As she explains,
I do “zone lighting.” I go into the location, wherever it is, before I’m going to shoot, and I look around. I observe where most of the movement in the house is. I have a meal with the family, and I see that they tend to be at the stove, the sink, and the table. I ask myself, which side of the table are people most likely to sit, where are they most comfortable? Sometimes you have to ask people, sometimes you can tell by the way things are set up. If there’s a lot of stuff on one side of the table, you know they don’t sit there. Sometimes someone will say, “That’s so and so’s favorite chair.” And then you say, “Well, where do you usually sit when you talk with him?”
Once you know where people are likely to be, you have to decide where your basic camera stance is going to be, so that you can set what is essentially your key light. And you can set any other fill lights that you might want to use.
I try to see where I can put up two—usually not more—750 to 1000 watt lights. I use a lot of practicals. If there’s an overhead light with a porcelain socket, I’ll remove the existing bulb and I put a heavier photoflood bulb in it. You have to put diffusion on it, and you have to be careful that it’s not too hot, and not throwing a lot of shadows, but the idea is that when the subject goes into the kitchen and flips on the light, it’s bright enough for you to get a good image.
Basically, you figure out where people are going to be, and you look for the most attractive ways to set the lights where there’s some subtlety, not just a wash of light. I really hate that video look where everybody’s nose blends into their face.3
Even though 1K lighting units may not be necessary for modern HD cameras, the principle of observation and zone lighting strategies remain essential today.
■ Figure 12.10 Casting the First Stone (1991) director Julie Gustafson’s observational approach depends on spending large periods of time with her characters in all sorts of situations.
In addition to the lighting, filters that affect the entire frame can be deployed to create a stylized effect. Barbara Hammer’s Resisting Paradise (2003) is a richly layered examination of the artist’s and individual’s role in times of conflict (Figure 12.12). It focuses on Henri Matisse and Pierre Bonnard’s artistic efforts in the south of France during World War II, while also examining the world of Matisse’s family and others in the French Resistance movement. To give a sense of how Matisse, primarily a colorist, saw the world, Hammer actually films scenes through washes of colored paint on glass.
■ Figure 12.11 In this shot from Franz Fanon: Black Skin, White Mask, the expressionistic lighting helps convey a sense of life in the shadows of colonialism.
■ Exterior Lighting
Shooting outdoors does not mean simply accepting the light nature has to offer. Here, time of day, weather conditions, and geographical latitude are key factors. When lighting exterior scenes, you must be crafty about the way you control your light sources, whether the sun during daylight hours or available artificial light at night. The following sections offer a few tips.
Location Scouting and Time of Day
When lighting is crucial, take the time to scout your location to figure out what time of day has the best light, and try to schedule your production around that time. Remember, the sun is constantly shifting, so when timing is critical make sure to schedule your call early, allowing for setup time so you’ll be ready to shoot when the light is just right. If your schedule doesn’t allow flexibility and you are required to shoot whenever you can get the location, you should try to scout the location at the time you anticipate shooting so that you have a good sense for the angle of the sun at the time you will be shooting. Typically, the more directly overhead the sun is, the less flattering it is to subjects, and many filmmakers will try to avoid filming exteriors during the middle of the day. Shooting in the shade can be an option, but the contrast between shady and bright sections of the scene can offer other difficulties.
■ Figure 12.12 Barbara Hammer’s Resisting Paradise (2003). This exterior, shot through a painted glass surface, gives an impressionist flavor to reality and emphasizes the role of color and light in the mind of the painter.
Check the Weather
To be fully prepared, regularly check a weather service to determine if it will be sunny, partly cloudy, or overcast. You should also be clear about the exact sunrise and sunset times. The degree of cloud cover drastically changes the tone and mood of an exterior image. Overcast days diffuse the sun, creating a soft, high-key look. Depending on the thickness of the cloud cover and the angle of the sun, there can be more or less directionality to this soft source. Sunny days produce a hard and bright light, which creates a very high-contrast situation. Exposures and lighting ratios have to be carefully considered on these days. Partly cloudy conditions, especially on windy days when the sun plays hide- and-seek, are particularly challenging because exposures can shift dramatically from one shot to the next or even within a single take.
Subject and Camera Positions
Just as with shooting indoors using artificial lights, your first lighting consideration when shooting exterior shots is where to place the key light. In this case, you cannot move your key (the sun) to change its directionality, but you can move the orientation of your subject and camera to get the angle you desire (Figure 12.9). In a street interview situation, this can mean “clocking” around the person you’re speaking with until the sun is in the most desirable position, usually behind you and illuminating him/her. However, as you rotate around your subject to find the optimum lighting angle, always keep an eye on what this is doing to the background of your composition.
■ Figure 12.13 Direct sun is used as a hard backlight and also bounced back onto the talent to provide a soft key (left). When subjects are in the shade (right), a reflector can bounce sunlight back onto the subject to get a better exposure and contrast range.
Sun plus Bounced Light
Perhaps the most useful lighting instrument for exterior shooting is the reflector (p. 175). If you use the direct sun as your backlight, then you can place a reflector (diffuse side up) opposite the sun, to soften and bounce sunlight to provide a soft key light. A typical placement would put the reflector low on the other side of the camera, filling shadows under the subject’s chin and adding eye light. One light source (the sun) thus becomes both a key and backlight (Figure 12.13, left).
Shade plus Bounced Light
When the direct sun is too intense, you can move your subject into the shade of a tree or a building. Heavy shade, however, can flatten out the image. In cases where this is not appropriate, you can always use the mirrorlike specular side of a reflector to bounce some of that hard sunlight onto your subject in the shade to add dimensionality to the image (Figure 12.13, right).
Using a reflector is a common strategy for changing the subject-to-background illumination ratio when you have a subject in shade and there is sun close enough to use as bounce light, making your subject brighter than the shaded area around him. This makes him stand out from the background, or “pop.”
Dusk-for-Night
Sometimes you want to shoot images of a location at night, but once night falls there is too much contrast between lit areas of the frame and unlit ones. A solution is to shoot at dusk. Just after the sun has set, there is still ambient light in the sky but streetlights, car headlights, and building lights start to turn on, creating a sense of evening while it is still light enough to shoot. Another concept worth mentioning here is magic hour, sometimes called “golden hour.” This is a period just before sunset when there is still enough light to film, but the strong shadows of normal daylight are missing. Although it is misnamed, as magic hour may be less than half an hour long, this period offers real cinematic “magic.”
Shooting at Night
Given the startling developments in camera sensitivity, it is more possible than ever to actually shoot nighttime scenes using available light and small portable lighting units for highlights and emphasis. You cannot shoot a scene in a farm field under moon light and expect to get an exposure, but in an urban context, if you keep your frame tight, shop window lights and bright street lamps can give you acceptable exposures. You can then augment these available sources with small, battery-powered lights. Nighttime shooting is tricky, and tests are especially recommended.
in practice
■ Making a Documentary in the Dark
For her documentary Border (2004), Laura Waddington spent months filming Iraqi and Afghani refugees at a Red Cross camp in northern France as they played a nightly game of cat and mouse with police trying to prevent them from hopping on trucks headed for England (Figure 12.14). The exposure levels were at the limits of what the small camera was capable of. Lighting mainly with car headlights, the occasional camera-mounted light, or the light of the dusk sky, Waddington was able to capture images of refugee life, efforts to flee punctuated by moments of police violence. Ultimately, the visual qualities of night shooting became the aesthetic core of the film. As one critic noted, “Shot secretly, the shutter wide open, almost in slow motion, the images create an aesthetic experience of fear, of terror, as if fallen out of a nightmare, peopled with out of focus figures.”4
■ Figure 12.14 Laura Waddington’s Border (2004) is shot almost entirely at night using a mix of headlights, on-camera light, and available light.
Camera-Mounted Lighting
One common lighting solution for difficult situations, especially those that involve a roving camera and a lot of subject movement, is a small camera-mounted light. In a dark setting with unpredictable lighting a camera-mounted light can make the difference between getting a scene and not. One of these lights will give needed exposure for a face in a nighttime crowd, or an object in an unlit room. However, the “sun-gun” look, reminiscent of the battery-powered lights of a television news crew with its tendency to create hot-spots and heavy shadows, may give your shot a crude “newsy” feel you don’t want. If you have assistance, a battery-operated portable light held above camera height will give a more natural look by dropping shadows toward the bottom of the frame. LEDs, or other lights that have a dimmer, provide a big advantage in camera-mounted situations.
■ Exposure: Beyond the Basics
Now that you are familiar with the issues that come up when lighting a scene, we can turn our attention to slightly more intricate issues related to lighting your scene, and the interpretation of that light through the camera’s electronics. We need to look a little closer at how the sensor actually responds to the various light values in a scene, beyond just its general sensitivity. Three additional concepts are essential to a more advanced understanding of lighting and exposure for video: contrast range, characteristic exposure curve, and dynamic range.
Contrast Range
Contrast range, also called “luminance range,” is the difference between the brightest and the darkest areas of the scene you are shooting. Remember, “bright” and “dark” consist of a combination of incident light intensity and reflected light values (p. 167). Even in a high-key scene, there will be tremendous variations in light levels. Contrast range can be expressed either in terms of a ratio, or in terms of the difference in f-stops between the two luminance extremes. For example, it is not unusual to discover, through multiple light meter readings, that a scene’s lightest area is 16 times brighter than its darkest area. We can express this as a contrast ratio of 16:1 or as a contrast range of 4 f-stops. Why? Remember that each stop is a halving or doubling of brightness, so 4 stops from darkest to brightest is 2 · 2 · 2 · 2 = 16. If the darkest area of your image reads 20 foot-candles, then the brightest parts will read 320 foot-candles. It should be noted that four stops is a relatively narrow contrast range. It’s not unusual to have a contrast range of 256:1 (8 f-stops) or even more (Figure 12.15). One central question concerns how much of this contrast range your camera’s sensor can faithfully reproduce.
■ Figure 12.15 Film is still the gold standard for its ability to handle contrast in an image. This scene from Kodak shows the contrast range in f-stops, from the dark wall to the left of the lockers (-2.5 stops) to the bright windows above (+7 stops) of their Vision 3 500T negative stock, a total of 7.5 stops.
Dynamic Range
Broadly defined, exposure range (also called dynamic range) is the range of luminance values your specific imaging device can render with detail before falling off into complete overexposure (blown out or clipped whites) or complete underexposure (crushed blacks), where no image detail is visible. Exposure range is expressed in terms of the range of f-stops within which the imaging device will see detail. It is often the case that the contrast range of a scene exceeds the exposure range of your imaging device, which means that visual detail will be lost either in the brightest or darkest parts of your scene, or both. Cameras vary in their ability to render detail in bright or dark areas of the image. For example, an inexpensive consumer video camera can handle 7 or 8 stops, while a higher-end camera like Sony’s A7S can handle about 12 stops. So if you want to truly control your image, it’s important to know both the contrast range of the scene you are shooting and the ability of your imaging device to render those exposure values. Once you know these facts, you can use camera controls and lighting to selectively bring areas of your scene into or out of the exposure range of your imaging device to create visual emphasis and interest.
In addition to the camera’s ability to record a broad range of light levels, there is its ability to monitor those levels. In many cameras, the viewfinder, particularly if it is a flip-out LCD viewscreen, deals with contrast poorly. For this reason, many cinematographers will use a good-quality field monitor to give a better idea of what is going on with the lighting.
Shooting with Dynamic Range in Mind
As we’ve suggested, dynamic range refers to the camera’s ability to reproduce light and dark aspects of a scene. When looking at a real situation, you will have to make choices about what is important to you in the scene. Do you care about the shadow detail, like the folds in a dark garment, or the curls in someone’s dark hair? If so, you can open up your aperture and let the highlights in the scene be overexposed. If what is happening in the brighter parts of the image are important to you, like how the clouds look in the sky, then you can stop down and sacrifice the detail in the shadow areas.
Although there are specific limits to what a particular camera can do, the ability of sensors to handle wide dynamic range is improving regularly. The gold standard historically was film, where the dynamic range (expressed as “latitude”) could be as high as 14 stops. Because of the demand for digital cinematography to replace film, many manufacturers offer ways to extend the dynamic range of their video cameras. We will explore some of these options below.
Characteristic Curves and Gamma
■ Figure 12.16 This figure shows a characteristic curve for a video image. The y-axis represents the light in the scene from dark on the left through a medium 18 percent gray to a bright 100 percent white on the right. This represents the input, or the light entering the camera. On the x- (horizontal) axis you can see the output, the amount of luminance in IRE units generated by the camera in response to this incoming light. The slight curve at the bottom of the image is the “toe” and indicates that the shadow detail falls off gently. The lack of a curve at the top or white end suggests that there will be no emphasis on detail in the white part of the exposure curve.
In addition to the range the camera can handle, there are significant differences in the ways different cameras reproduce the light within that range. For example, two cameras might have the same range of 8 stops, but respond quite differently. That difference is represented graphically in the characteristic curve (Figure 12.16). In a sense, the characteristic curve represents a camera’s personality, how the sensor responds to the light hitting it. Imagine a medium level gray that a camera sees. It can represent that gray as it is, or as a bit darker or lighter. Another camera will respond differently. These differences in characteristic curve mean that one camera may offer more shades of gray at the dark end, adding shadow detail, while another may show more of the differences in highlights. This can be a bit complicated at first, and it is much easier to visualize when you actually start comparing cameras.
In many cameras, you can influence the characteristic curve of the camera’s imaging by changing settings, most notably the gamma. Gamma represents the capacity of an imager to differentiate between the various luminance tonalities (shades of gray) in a scene and is represented by the angle of the straight-line portion of the curve—in other words, the steepness of the slope. The ideal angle for a straight line would be a perfect 45°, meaning a perfectly proportional increase in density to exposure. This would faithfully duplicate all of the subtle shifts in the gray scale (Figure 12.17). However, the human eye does not work the way a video sensor does, so a “perfect curve” doesn’t necessarily look pleasing to the viewer.
Changing your camera’s gamma setting allows you to choose which part of the curve you want to expand or compress. Canon, for example, offers nine different gamma settings. Cine 1 “softens the contrast in darker regions and emphasizes gradation changes in lighter regions,” while Cine 3 provides a “stronger contrast between light and dark regions, and greater emphasis on black gradation changes.”
Black Stretch, Knee, and Log Gamma
An additional detail of the characteristic curve that is greatly affected by the angle of the curve slope in the toe (the dark end of the curve) and the shoulder (the bright end). Video circuitry creates a signal with no toe and no shoulder, which means a hard clipping of whites and an abrupt plunge into inky blacks when the exposure approaches the extremes of under- and overexposure. Without the curved toe and shoulder at the ends of the exposure limits of the imaging device, the video image not only fails to duplicate the film’s gradual tapering off of detail toward total black or total white, but it also loses out on a few stops of usable exposure range.
■ Figure 12.17 Here the same still image is shown with no changes in gamma (top), with a gamma curve that minimizes contrast in the midrange (middle) and one that emphasizes contrast (bottom). The graph next to the picture represents the characteristic curve for each image.
Black stretch is a setting that can extend the sensor’s sensitivity in the darkest parts of the image so that you are able to see somewhat more detail in the shadow areas of the shot. Engaging black stretch is the equivalent of creating a “toe” in the characteristic curve. You will see a little taper to the extreme underexposures, which means that things at the darker end of the light range fade off gently, offering more shadow detail, and you gain about one stop at the bottom end. Black stretch is like a video gain function that selectively boosts only the darkest portions of the image. As with video gain, you need to be careful that you don’t overdo black stretch because you can introduce video noise into an area that was otherwise clean, or you can create blacks that are not rich (called milky blacks) in all portions of your image that are black. Some of the work of black stretch can be more accurately and safely accomplished in two ways: careful lighting of the dark areas of the image (when you have lights) so that you bring those areas into your dynamic range or through postproduction color correction (pp. 364–365).
Video is especially vulnerable to overexposures that commonly show up in two circum stances: highlights on prominent areas of a subject that reflect the key light, like cheek bones or foreheads, and in situations of extreme contrast ratio, like bright windows visible in a dark interior location. This overexposure, called clipping, can be avoided by the careful use of zebras (Chapter 11), but even without overexposure, bright highlights can cause an extreme and uneven loss of color saturation and detail in the image. Video knee is a signal compression adjustment that is the equivalent of creating a “shoulder” in the signal’s response to intense exposures. Many HD cameras allow for manual setting of the upper signal levels (near the ultimate white clip level), allowing more detail to be visible as you approach total overexposure. Attenuation of extreme white levels can be set at 80 percent (low), 90 percent (mid), and 100 percent (high). The earlier you set knee to kick in, the more detail you’ll see in your highlights. The drawback is that setting knee at 80 percent can make your whites look gray. Many cameras now have an easily accessible automatic pre-knee setting, called auto-knee (also called auto highlight control), designed to give you maximum detail depending on the highlight values of the particular image in the frame. Auto-knee is one of the few auto settings that you might consider leaving on while you shoot, but it works best with static frames. A shot that pans across bright areas will reveal the processor adjusting as it detects highlights and corrects on the fly.
As mentioned above, many cameras now offer gamma settings that give video a more filmic look by softening the top and bottom of the exposure curves, meaning that the camera’s exposure eases into shadow and high-light areas. One of the most common signal tweaking functions is CineGamma. CineGamma (aka Cine-like, Cinematone, or Film Rec) electronically flattens the straight-line portion of the video signal’s characteristic curve and introduces a shoulder to the highlight areas. This accomplishes two things simultaneously: it slightly extends the dynamic range of the camera, and reduces the contrast of the image, thus ameliorating the video’s “crispy” electronic look. With CineGamma, you’ll see more detail in the shadows and highlights. The drawback of this setting is that the overall reduced contrast of the image can, in some cases, create washed out midtones and colors (Figure 12.18).
■ Figure 12.18 This woodsy yard is represented in three of the different gamma modes available on the Canon C100. The top image is standard mode, which looks fine but risks burning out the highlights, such as those on the bench in the foreground. The middle image was shot with Wide DR to add several stops to the exposure range. The image looks darker here, but has much more picture information in the highlights. The bottom image was shot in the Canon Log mode, creating an image that looks murky to the eye, but will respond well to color grading in postproduction.
Log gamma settings stretch the dynamic range of the image to the maximum the sensor is capable of, which can mean going from 10 or 11 to 12 or more stops (Figure 12.19). The resulting image has lots of highlight and shadow detail, but looks flat and quite unnatural until it is corrected in postproduction. In fact, another name for this approach is shooting flat. Shooting with log gamma means that your workflow in postproduction will have to include color grading (Chapter 22). For documentary work, one alternative is an extended dynamic range setting (Wide DR in this case), available on some cameras, that demands less work in postproduction (Figure 12.18, middle).
■ Figure 12.19 Log gamma (Canon Log in this case). Like many manufacturers, Canon offers two options to create a broader exposure range. Wide DR and Canon Log modes offer several extra f-stops, indicated by the longer curves.
Always use caution and moderation when you use any of these settings. Altering the electronic signal of your camera can have unintended consequences. If you’re interested in using black stretch, video-knee, or Cine-Gamma, make sure you shoot tests before going into production. Also remember that adjusting the signal is not a substitute for careful, sensitive, and creative attention to lighting and exposure.
Color Settings
Video cameras also typically have a color “look.” People will argue about the warmth of one camera’s image vs the naturalness of another. Most cameras now have a variety of color settings, which affect how the camera reproduces color. A discussion of these is outside the scope of this book, but if you have a particular idea about color reproduction, you should investigate these settings on your camera.
■ Conclusion
As you’ve seen, documentary lighting isn’t just a matter of throwing light onto a scene so that we can make out the physical subject. Lighting is communicating visual ideas and inflecting the film with a mood, a tone, and a visual context. The approaches we’ve explored in this chapter should give you a solid sense of how you can get started in creating the lighting approach that best suits the story you are telling.