Trick For Shooting Interviews With Only 1 Light
INTRODUCTION
A cinematographer’s biggest enemy are images which look flat. The best way to counteract this is by introducing contrast: which can either be done by using different areas of light and shadow, or by using different colours.
So, let’s take a look at a specific type of colour contrast in an interview setting: warm and cool tones, and show how you can very simply create images like this by using only a single film light.
COLOUR TEMPERATURE
When an object is heated to a high enough temperature, it emits light. This light can fall across a range of different colours - and is commonly measured through the unit Kelvin.
A lower Kelvin value represents light sources which are considered warmer: for example an incandescent light bulb. Whereas cooler or more neutral sources of light, like sunlight, will have a higher kelvin value.
Although there are a whole host of different light sources that can be used which come with a diverse range of cooler and warmer colour temperatures, I’d say there are 2 main Kelvin values which are most often used by filmmakers.
The most popular warm light source is what we call ‘tungsten’ - which has a value around 3,200K - the value that old tungsten filament incandescent bulbs give off.
The other popular cooler light source is ‘daylight’ - at 5,600K it’s the approximate temperature of natural sunlight.
Before LED lights, which are now capable of easily changing to a range of different colour temperatures, most film lights either emitted tungsten light or daylight. Whether that was the warmer incandescent bulbs, fresnels, par cans or dinos, or the cooler daylight kino flo bulbs, HMIs, or even the sun itself.
Because of this, film stocks were designed to capture light at either a 3,200K tungsten balance, or a 5,600K daylight balance. These same Kelvin balances can be found on digital cameras, as well as giving you the option to dial in a custom Kelvin value anywhere in between.
However, many cinematographers still stick to filming with the camera colour temperature set to either 3,200K or 5,600K.
WHITE BALANCE
Let’s take a look at what happens when you shoot cameras in different lighting conditions at these two different Kelvin bases.
If we set the colour temperature on a camera to be 5,600K and we light it with natural sunlight that also has a Kelvin value of 5,600K, then the image will have true, natural colour.
However, if we keep the camera at 5,600K and instead light with a 3,200K source, then the image will appear warm.
But, if we keep this warm light and change the colour balance on the camera to 3,200K then, again, the colour will be captured with a true and natural look.
However, if we take that same camera set to 3,200K back outside under natural sunlight, then the image will be cool.
COLOUR CONTRAST
If we circle back to the beginning, I mentioned how cinematographers often make footage more interesting by lighting with different colour temperatures in the same frame - to create contrast.
If those different colours are placed at different planes of depth, it can also make images feel a bit more three dimensional.
An easy way to apply this idea is to light the subject in the foreground with light that has a different colour temperature to the light that is in the background.
For example, lighting the subject with a lamp that is a warmer 3,200K, and lighting the background with a cooler 5,600K light.
One of the reasons that this is quite visually pleasing is due to complementary colour theory.
If you look at a colour wheel, complementary colours are those which are opposite each other. Because of this contrast they are often viewed as being visually pleasing when placed next to each other. So a green and a red are complementary, or, for the sake of this video, a warmer, orange colour and a cooler, blue colour are complementary.
TUNGSTEN INTERVIEW SETUP
For this first interview setup we’re going to set the colour balance on our camera to 3,200K in the menu. Then we’re going to place our subject in a room, and turn off the house lights, so that she is only illuminated by the natural ambient sunlight coming through the windows.
Because the camera is set to 3,200K and the light source is about 5,600K the image will have a cool colour tint to it. So, even though we haven’t set up any film lights yet, we already have a nice monochromatic blue that we can use - compliments of the sun.
In order to get a natural looking skin tone I want to set up our light to have the same colour temperature as the colour balance on the camera - so 3,200K. To soften the light quality of the 500C I’m going to attach a softbox to the front of it, then to make those shadows even more gentle and pretty I’m going to shine the light through a second layer of silk diffusion which I’ve rigged to a stand.
The issue now is that, although the key light on the subject looks nice and soft and natural, our film light is also hitting the wall in the background of our shot. If you’re going for more of a high key look then this may work, but since I want to create a bit more colour contrast it’s an issue, since the 3,200K film light overpowers the natural 5,600K sunlight in the background.
I’d also like for the background to feel a little bit darker to create more of a light and dark contrast between the subject and background.
I’m going to use a trick called flagging the light. All this means is that I want to stop the light from hitting the back wall, yet still have the light hit the subject. To do this I’ve very simply rigged some blackout on the one side - so that it blocks the light from hitting the background.
So there we have it, a simple interview shot with the camera set to 3,200K, the key light also set to 3,200K and letting the 5,600K natural ambience from the sun fill in the background.
DAYLIGHT INTERVIEW SETUP
I’m going to shoot our second interview setup at night, using the same idea of colour contrast, but just flipping things around a bit. Here, I’ve set the colour balance on the camera to 5,600K.
Technically I’m actually going to use more than one light here, but these lights are not film lights. They are what we call practicals - lights built into the set which can be seen in the shot. For example a lamp and an incandescent ceiling house light.
To my eye these pracs actually look to be a bit warmer than 3,200K, but they’re somewhere around that ballpark. Since the camera is set to 5,600K and these are around 3,200K they will read much warmer than neutral light.
Then, like I did in the previous setup, I want the key light to be the same as the camera’s colour balance - 5,600K - with our practicals in the background somewhere around 3,200K.
Another reason for placing a secondary light source, like a practical or natural sunlight, in the background of the shot, behind the subject, besides creating a colour contrast, is because it gives a subtle back light to the subject, which will help to create a bit more separation and depth in the frame.
As I did last time I’ve also flagged the key light off the back wall to make the background a bit darker and better emphasise the colour contrast.
There we go. Two different, simple setups that both use one film lamp and play with the idea of colour temperature to create frames with a bit more depth and contrast.