Lighting and photography go hand in hand. Without light, we’d have no photos! However, light is not only important on a technical level, but also an artistic level.

You may take the same shot multiple times, but varying the angle and degree of lighting on the subject can create a drastically different mood for each shot.

It’s amazing how much the adjustment of a single light source can amplify your photography and bring professional levels of variation to your portfolio. So it’s no wonder we’re directing our focus to what a key light is and how to use it in your next shoot.

Image by Tim Johnson

What’s a Key Light, Anyway?

If light is a stage performance illuminating the world of photography and its many possibilities, then the key light is its main actor. Of all the light sources contributing to the overall lighting of a photograph, the key light is the light which is often considered the most important.

A key light functions best within two different roles, and you may choose to use a key light in either one of these ways depending on your goals for the portrait and the photograph’s background.

• A key light may be used to mimic natural lighting. In other words, a key light can serve as the scene’s overall lighting, which brightens every aspect of the scene equally.
• On the other hand, a key light may also be used as a way to emphasize only the subject of a photograph rather than the entire scene.

The term “key light” is frequently misused. When there is only a single source of light contributing to a photograph, that is not a key light. Instead, a key light exists in multi-light setups because, of all the lights participating in a scene’s lighting, the “key” light must truly be, well, key!

The Many Ways to Use a Key Light

While the basic definition of a key light is simple enough to understand, implementing a key light effectively within your studio can become a surprisingly complex endeavor!

Like any other aspect of photography, a key light can be manipulated to better fit your vision for a portrait’s mood and composition.

These various key light patterns are essentially limitless in number, though some are used more commonly than others to amplify particular visions. For example, you may choose to use a key light for:

1. Flat Lighting

   The most common lighting pattern, flat lighting, directly faces the subject at the same angle as the camera lens. This won’t yield any shadows, but it’s great for reducing the appearance of fine lines.

2. Split Lighting

   Adjust the angle of your key light by moving it 90 degrees to the left or right of the subject. This will illuminate half the face, leaving the other half in dramatic shadow.

3. Three-Point Lighting

   Some photographers choose to utilize a fill light and a backlight in addition to their key light for a total of three lights.

You may also choose to differentiate your key light usage into hard or soft light, depending on the types of shadows you want to be cast on your subject’s face. Hard lighting creates sharper, more dramatic shadows, while soft light will create gentler shadows and contribute more subtly to lighting variations.

Other Lighting Tricks

Understanding how to manipulate key light patterns is only a part of the overall concept. To fully grasp the concept of a key light and its secondary light source assistants, you’ll also need to understand how natural lighting can affect your setup and how you can further manipulate the key light with alternatives.

1. Key Light Alternatives

Sometimes, photographers may not have access to a piece of equipment to use as a key light, a light source that they can adjust and position at will to create a portrait’s primary light source. In these cases, there are a few ways to get creative and create a key light out of something else entirely.

For example, you can utilize a camera’s flash, reflectors, or even sunlight as a key light for your next photoshoot. For example, the sun may act as a key light, while reflected light serves as a secondary light source.

In short, you don’t have to have key light gear to use key light intelligently in your composition!

2. Introducing Secondary Light Sources

Other situations often occur when you have access to only a single light source, but you still want to implement the use of a key light in your composition. To create a secondary light, try using reflectors to introduce other lights into a scene that might otherwise have only a single source. Then, the single source may be considered the primary light source (the key light), while the light introduced via reflectors acts as the secondary light.

With a better understanding of lighting will come better photos, so never underestimate the power of learning more about key lights and all the ways they can be used for more impressive shots!