Christian Berges: Portrait Lighting Basics. Part 1 – The Key Light

The key light is the most important light. It’s the key to your lighting setup.

It can be your only light. It should be the first light you’re concerned with. Perhaps it’s already there – just look around. Is it the sun shining through a window into the room? Or is it a desk lamp close to your protagonist? You have to find it, use it, manipulate it, sometimes amplify it. Or block it, if it’s not the kind of light you want – maybe it’s coming from the wrong direction, maybe it’s too strong, too weak, too punctual or too diffuse.

When there’s no suitable available light on your location, you’ll have to set up your own. But what is a proper key light? What function does it have? What is the right direction and angle?

Function

The key light reveals itself: It’s the light that defines the lighting direction within your composition. It has an evident direction. It is traceable because it casts shadows. Everybody can see – or at least subconsciously feel -  where it’s coming from, even if the light source isn’t visible in the picture. That makes the key light predominant within  your setup. And unique.

Your key light can be naturalistic by imitating a natural light source like the sun. Or it can have dramaturgical function and make people look beautiful, ugly or even diabolic. Apart from the softness of your light source, the effect depends mainly on the direction the light comes from.

Direction

Where do I place my key light? What angle should it have in relation to the camera and the protagonist’s viewing direction? What height should it have?

There are two reasons why these questions are hard to answer. First, there’s no universal solution – ‘good’ portrait light is a quite subjective matter.

And second, it depends on the the effect you want to achieve: Do you want your protagonist to look rather natural, artificially raised or – for whatever reason – even crude or evil? If you really want to portray someone in a diabolic way, just let the light come from a low angle below his face. The nose will cast an ugly shadow, and the eyes look spooky.

But that’s a quite specific and unusual application. In most cases, if you shoot a portrait or light an interview, you want your protagonist to look as good as possible. Let’s stick to this aim.

There are still a lot of possibilities as to direction and angle of your light source. Some key light positions make sense, they just work. Others don’t. Try to judge on your own what you like or what you don’t like.

Let’s take any light source and move it around our protagonist’s face. It’s a good way to experience the effects of different angles. Where do shadows occur? Which shadows are unproblematic, which are critical, annoying or even enriching?

For the time being, don’t care whether it’s a spot or a soft light – let’s just concentrate on the direction the light comes from. But of course: the more focused your light source is, the more accurate the lamp’s position has to be.

Soft light is more ‘forgiving’.

If you don’t want to overstress or bore your model, just exercise with a display dummy or a puppet’s head. You’ll easily find something affordable to practice with on internet auction platforms.

a) Frontal Light

It’s the most obvious position for your key light: just place it above your camera, as close to the lens as possible. What you get is a homogeneous illumination of the face. There’s hardly any shadow – just a very small one beneath the chin, depending on the distance between your camera’s optical system and your light source. If you use a ringlight fixed around your lens, light axis and camera axis are identical. There will be no shadow at all.

A benefit of this technique is the beautiful eye light showing up exactly in the middle of your protagonist’s pupil: The reflection of your key light make the eyes look alive.

Frontal light can be a pretty beauty light – if the face is interesting enough to impress on it’s own. Or if the focus is on the makeup.

This light position is most recommendable for high key portraits. If you use a bright background and overexpose your picture, you’ll get the typical shiny, shadeless look.

But frontal light can also look quite boring. It tends to makes a face appear flat, two-dimensional and broad. That might not suit every model…

So let’s move the key light. First upwards.

b) High Frontal Light

If you keep your key light right above your camera and start to move it slowly upwards, you will observe growing shadows. First, they appear underneath the chin, then they get more and more obvious below the nose, finally even within the eye-socket.

High frontal light is also called ‘glamour lighting’ – it’s often used to flatter a woman’s face by making it appear leaner. This works best with oval-shaped faces and strong cheekbones. Marlene Dietrich made this lighting technique popular – she insisted to be pictured this way.

Another term for a high frontal light is “butterfly lighting”. This refers to the shadow that is formed below the nose, conjuring up the image of a butterfly’s wings. Keep this expression in mind – it helps you find the right position for your ‘glamour’ key light: Stop moving your lamp upwards before the butterfly becomes too fat. The nose’s shadow shouldn’t exceed half the distance to the upper lip.

c) Slight Sidelight

Let’s move the lamp down again, just until the shadow below the nose disappears and the shadow underneath the chin is minimal.

Then start moving your light source slowly sideways… let’s say to the left. There’s a growing shade on the right cheek, on the whole right side of the face (from the photographer’s point of view). And also on the right ala of the nose. Stop moving your lamp sideways before the nose casts a shadow.

What you have now is still an almost frontal light which has moved just a little bit sideways. What you gain with this position is plasticity:

With the slight shade on one side, the face looks more three-dimensional and shaped, almost narrowed.

This kind of slight sidelight is also a very common key light position for video interviews. Usually, the protagonist doesn’t look directly into the camera’s lens, but to the interviewer who is sitting as close to the camera as possible. This setup has become a standard for television interviews in documentaries,  features and news. It combines two advantages: The reporter can keep eye-contact with his conversational partner while the audience isn’t confronted with a direct address – it remains in the position of a distanced observer.

Now you have a situation in which your protagonist’s nose isn’t pointing directly to the camera. It’s not yet a semi-profile, but the face has turned a little bit.

Adopt your slight sidelight by keeping it’s angle in correlation to the nose. You’ll have to move it a little bit further to the left – keep the right wing of the nose shaded, but stop before the nose’s shadow appears.

In my experience, your final setup will look like this: You position your camera, put a chair for the interviewer close to it, followed by your light source.

Now we move our key light a great step further to the left – until it shines from a 90 degree angle to the axis between camera and protagonist. Still, it remains almost on the the camera’s height.

The resulting impression is an extreme division of the face into two halves – a bright and a dark side. This is a strong effect that can look quite interesting – but it also has a sinister aspect. Use it with care… consider if it makes sense in dramaturgical respect.

Of course, you can reduce the extreme contrast between dark and bright side of the face by adding an adequate fill light… this will be the topic of my next tutorial.

e) Rembrandt Lighting (the Rembrandt Triangle)

This is a beautiful and exciting , but maybe also the most demanding position for your key light. Dutch painter Rembrandt often used this technique in his paintings. It’s a variation of the sidelight. The difference is that the shadowed side of the face regains a little bit of illumination – just a small triangle below the eye. This is called the “Rembrandt Triangle”.

The impression is both naturalistic and dramatic. Naturalistic because your lamp imitates the high angle of a very common light source: the sun.

And dramatic because of the fascinating interaction of light and shadow on the face.

To achieve this effect, you have to move your light source up and a little bit back towards your camera. Just try to find the correct position to create the small triangle under the eye. Observe the nose’s shadow and keep this in mind:

It must melt into the cheek’s shadow, but it shouldn’t overlap the upper lip. The aim is to let the nose’s ugly shadow disappear in the dark areas of the face.

Try to keep the eye light – the small reflection of your key light on the protagonist’s eyeball that makes him look alive. That may be difficult or even incompatible with the light position the Rembrandt triangle requires, depending on the face’s proportions.

Actually, the eye light is missing on most of Rembrandt’s paintings. But don’t worry if you want a less gloomy look: You can regain a vivid eye light with the fill light you’ll probably need anyway to brighten up the shadows.

While a frontal key light is a good choice for high key photography, the deep shadows of Rembrandt light work well with low key shots using a dark background.

Of course, this is also an interesting lighting setup for video and television interviews – but you need to have nerve! It’s risky because it’s not still photography… and the protagonist may move his head while he’s talking.

Most critical is any movement towards the light source – the nose’s shadow gets shorter, loses touch with the cheek’s shadow and may be perceived as a disturbing, ugly structure.

Decide for yourself if you want to take the risk. Or play it safer with an elevated sidelight coming right-angled from the direction where the interviewer sits. When the protagonist moves his head towards the light source, the Rembrandt Triangle will appear. Meanwhile, you still have a nice sidelight.

© 2011 Christian Berges
www.bergesmedia.de