Film is often thought of as a combination of light and sound. Light is one of the most important parts of your role as a photographer or cinematographer. It will offer some of your greatest challenges, but also opportunity for your greatest creativity. The difference between a good shot and a bad shot is often lighting.
Okay, so lets talk about light. Before we get into the practicalities of how to light a scene, there’s a little bit of light theory we should touch on.
All light has a colour temperature, or a hue of colour that is casts. This temperature is measure in degrees of ‘Kelvin’, named after phycisist William Kelvin. The measurements are taken from what colour a ‘blackbody’ burns at (originally a block of carbon) at increasing temperatures. Colour temperature is measured on a continuum from blue (higher kelvin 5,500K+) to red (lower kelvin, 2,200K and below).
So what does this mean for you? Well, on an average afternoon with the sun high in the sky, the colour temperature will be 5,500K, at sunset/sunrise, around 2,000, by the light of a candle your looking at around 1,700K and indoors by the light of tungsten (the standard light used for film) around 3,000K. Our eyes adjust naturally to these differences and we are easily able to distinguish what white is in a variety of circumstances, the camera has a bit more trouble. This means that you need to adjust your white balance, or set a custom white balance, as you move to different locations, or as the light changes.
It also means that its important to pay attention to what kind of light is in your scene. Is the light all from the same source or is it from different sources? Do the different sources have different colour temperatures? Is this a desirable effect? Does the cool daylight in the background add something to your shot, or does it make it look unnatural and unsettling? These are all questions you should be asking yourself when thinking about colour temperature. Generally I will try and isolate and utilize one type of light source so as not to muddy the colours in my shot, but sometimes will use both to create dramatic lighting.
Note: Fluorescent lights also have a colour temperature, however, whilst still having different shifts along the red to blue axis, they also have a slight green shift, on the magenta to green axis. This can lead to that ‘office’ look, popularized in Fight Club. Fluoro’s made specifically for photography are available that have less of a green shift, however, try to avoid shooting with normal fluorescent lights as they have a green tint, and often produce ‘flicker’, because of the way they produce light (gas discharge as opposed to incandescence). LED lights are also another popular option that avoid some of fluorescents shortfalls.
Shooting outdoors will often yield great results. Natural light looks beautiful and natural, where studio lighting, when done improperly, can look contrived. The trade-off is that you don’t have control over natural light. When shooting outdoors its good to take stock of the weather, and to know how to properly take advantage of the light you have.
Shooting in the shade on a sunny day may be necessary in order to keep your talent out of the hot sun, or because you can’t move your subject. What you want to watch out for here is highlights. When you expose for the shade, the parts of your shot that are in sun may ‘blow out’ or overexpose. This can be troublesome, as shadow can often be recovered using post-processing, whereas blown out highlights are unsalvageable (note that the opposite is true if you are shooting film instead of digital). You can have a similar problem on a partially cloudy day, when the sun is dipping behind the clouds, and then coming back out. You’ll find as you expose for one setting, the sun will come back out and your shot will be overexposed, similarly if you expose for another, the sun will go away again and underexpose your shot. In these situations its best to find a different location, and if you must stay, then be vigilant with your camera work.
Aside from the colour temperature changing over the course of the day, so too will the ‘quality’ of light. Early in the morning and towards sunset, the sun casts long dramatic shadows, and the light being bounced underneath the clouds as opposed to off the top of them, has a soft warm quality to it. The hour just before sunset and just after sunrise is typically known as ‘Golden Hour’ and is when many photographers choose to work. Sunrise can provide mist and beautiful dew on plants. As the day goes on, and the sun rises further, the quality of light diminishes. When it is at its highest, the sun casts deep shadows in eye sockets making people look sinister. There are however less reflections on still water at this time and it can be a great time to capture some ocean or river shots with stunning clarity. Architectural photography is also much more dramatic in the early morning or afternoon hours, as the shadows created by the shapes of building give them a sense of depth and drama.
This is a good tip for outdoor photography. Shoot with the sun at your back. If you shoot with the sun on your back, then light should be plentiful on whatever it is you want to shoot. Doing the opposite can result in silhouetted subjects and unsightly shadows. Sometimes you may want to break this rule, for a silhouette shot for example, or for interviews, to spare people from looking directly into the sun. When interviewing someone outdoors, the direct sun in their eyes can be a bit much and may throw off their interview, some solutions to this include picking a shady spot, or turning them so they are sidelit, instead of frontlit or silhouetted. Do not let them wear a cap or glasses, unless it’s relative to your story. Hats and shades cast shadows on the face and eyes, and obscure key features like the hair or eyes. This is your audience’s opportunity to connect with this character, and it is very difficult if they can’t see their face.
When shooting outside, dappled light can look very beautiful, when there isn’t too much contrast between the shade and light. It can give a very calmative and intimate feeling to your shots. Out of focus light points, or Bokeh, can really help to give your shot a beautiful feel as well, and light shining through leaves provides a safe and intimate feel.
Sometimes you won’t have time to set up lights indoors, or you may not have to as you find your scene already perfectly lit. If you find yourself in one of these situations, try using light from a window, or a doorway to cast light on your subject. If you have to work with overhead lights, try not to put your subject directly underneath the light, as this will cast deep shadows underneath the eye sockets, creating a sinister look. Remember to try and think about and assess the quality of light available(see experimental light) and try to think about how to get the best out of what you have to work with. Work with the light you have, not against it.