Lighting and its function in cinematography

Cinematography is the art and science of recording moving images. Through lighting we can create in these images a visual language that indicates time, place, and three-dimensionality. Lighting can do a lot, but it has several major functions in photographing moving images.

ILLUMINATION AND SELECTIVE FOCUS

Just as light allows us to see, lighting allows us to record the image. Obvious, right? But we need to consider the following. Our eyes register light through rods (brightness on a gray scale) and cones (color values) and transmit images to the brain. They are very sensitive and have a tremendous amount of latitude in what they can perceive and what the brain can then process or “record.” At the writing of this book there are a lot of very excellent high-definition cameras being used in the profession. They range from the ARRI ALEXA and the RED to the Sony F55. There is also a wide range of “prosumer” and low-budget professional cameras being used for a wide variety of digital cinema and video production, which includes the Sony NEX-FS700, the Canon EOS C500, and a slew of digital single-lens reflex still cameras that can also record video and that all boast 35mm sensors and high resolution rates. They can record an image under almost any form of available light, even under streetlights outside at night or by the light from a computer screen. Amazing! Yet none of them come anywhere close to what our rods and cones can detect. The human eye can see detail in the darkest shadows in a room with only a single candle. It can see details in the texture of the snow on a sun-drenched mountaintop.

Lighting allows film and video to record an image that approximates what the human eye sees. Without enough light, the image, or parts of it, will be noisy, blurry, burned out, dim, and lacking in detail, if visible at all. While a lot of things can be done to the image in digital postproduction, it takes a lot of time, talent, and money—and can degrade the image quality. Even with the most advanced postproduction coloring software, it is still preferable to begin with a full-range, deeply saturated image—something we used to call a rich negative. That means a picture with a defined contrast, full blacks, clean whites that don’t blow out, and a nice full range of in-between levels throughout. We can usually only accomplish this by judiciously adding some of our own lights.

With the new highly sensitive sensors, the need to add light for simple exposure has all but disappeared. That burdensome, nonartistic, technical requirement has been, thankfully, lifted from the shoulders of the director of photography (DP) and gaffer, who can now concentrate totally on the artistic use of lighting. In other words, we now concern ourselves with how much we want the viewer to see and how much we want hidden in the shadows or ignored in burned-out white. In lighting we put light where we want it and take it away from where we don’t want it. We now have more ability to be selective in what we allow the viewer to see—selective in the brightness, in the color, in the contrast, and in the detail.

By using this selectivity, we can direct the focus of the viewer’s attention to what we want the viewer to concentrate more on within the picture. The human eye is attracted to whatever the brightest thing is in its view. Magicians use this to their advantage all the time. A bright flash of light occurs off to one side and everyone looks at it, giving the stage crew enough seconds to hide an elephant and make it appear to disappear (yes, it’s been done). Directors, art directors, and DPs use the same concept. Art directors will give the actress that is the star a more colorful, brighter, or more sparkly costume than the characters surrounding her, thus making her stand out in a crowd. DPs do this with lighting.

ILLUSION OF REALITY AND MODELING

Movies and videos are two-dimensional images. But everyone working on the project wants to suck viewers into the world being shown onscreen—we want them to feel as if they are looking into another world through a window. We want them to become so engrossed in the story that they feel like they are in the picture themselves. Lighting suggests a belief in the reality of what is on the screen. We use lighting to deceive the viewer into believing what is happening is real. We want viewers to forget that what they are watching has already happened a while ago and isn’t happening right here and now, and that who they are watching are actors, that the actors are just reciting written lines, and that they are in sets, not real locations. Good lighting renders an illusion of three-dimensionality to a flat screen, making it feel all the more real and making the viewer feel more present. Lighting does this by providing modeling and depth to an otherwise flat image.

The mind rejects pictures that are false and confusing, thus taking the viewer out of the moment and back into the position of sitting looking at a screen. This causes the viewer to separate from the story and examine the image as an image. When this happens, the viewer becomes detached from the story. While viewers certainly can become reengaged, they will not process fully what was going on or being said while their brain was preoccupied with trying to justify the “reality” of the image.

In order to avoid this, the lighting in the image must look “real” or “natural” or at least story-appropriate. Lighting provides logic. The light seems to be coming from natural or logical sources, making us feel we are in real locations. Lighting utilizes light, shadow, color, texture, and angle to give the audience a perspective on the scene taking place. Shadows must be consistent with the “source” of the light whether seen or unseen. We must be consistent to maintain believability. And believability is key to getting the audience to suspend disbelief and become involved in the story.

In order to maintain an illusion of reality, we will want to light the scene as if it were lit by a motivated light source—something that seems believable, such as a desk lamp, a window, or a fireplace. Thus, the lighting we use should be consistent with its source—in color and intensity, texture and angle. This helps the believability of the image, which helps the believability of the story.

These are only two of the functions lighting performs in cinematography. In the next post I will examine the others.